WO2025065652A1 - Communication method and apparatus - Google Patents

Abstract

A communication method and apparatus, the method being applicable to non-terrestrial network (NTN) communications. The method comprises: a first network device acquiring first information, and sending the first information to a terminal device, wherein the first information indicates information of an area, the area is fixed relative to the earth, and a geographical location of the area is determined by an identifier of the area; and after receiving the first information from the first network device, the terminal device determining, on the basis of location information of the terminal device and the first information, an identifier of a first area, and, on the basis of the identifier of the first area, performing mobility management, wherein the first area is an area where the terminal device is located. Based on this solution, the network device can indicate the information of the area to the terminal device, so that the terminal device can acquire an area distribution condition on the basis of the information of the area, thereby performing mobility management on the basis of the location information of the terminal device and the area distribution condition. Compared with a network device directly configuring reference point location information to enable a terminal device to perform mobility management, the present solution can reduce signaling overhead.

Description

Communication method and device Technical Field

The embodiments of the present application relate to the field of communications, and in particular, to communication methods and devices.

Background Art

Non-terrestrial networks (NTN) have significant advantages such as global coverage, long-distance transmission, flexible networking, convenient deployment and no geographical restrictions. They have been widely used in many fields such as maritime communications, positioning navigation, disaster relief, scientific experiments, video broadcasting and earth observation. NTN networks can be integrated with terrestrial networks to complement each other and form a global seamless integrated communication network covering sea, land, air, space and ground to meet the various business needs of users everywhere.

In terrestrial networks, cell switching or cell reselection is usually performed based on signal quality. However, since the near-far effect is not obvious in NTN, the efficiency of cell switching or cell reselection based only on signal quality is low. Therefore, NTN proposes a mobility management method based on location information, such as mobility management based on the distance between the terminal device and the reference point of the source cell and the reference point of the target cell.

However, in the above-mentioned location information-based mobility management method, the signaling overhead of the network side performing mobility-related configuration (such as the reference point of the cell) is relatively large.

Summary of the invention

The embodiments of the present application provide a communication method and device that can reduce signaling overhead.

In a first aspect, a communication method is provided, which can be executed by a terminal device, or by a component of the terminal device, such as a processor, a chip, or a chip system of the terminal device, or by a logic module or software that can realize all or part of the functions of the terminal device. The method includes: receiving first information from a first network device, the first information indicating information of a region, the region is fixed relative to the earth, and the geographical location of the region is determined by an identifier of the region; determining an identifier of the first region according to the location information of the terminal device and the first information, the first region being the region where the terminal device is located; and performing mobility management according to the identifier of the first region.

Based on this solution, the ground can be discretized into some fixed areas relative to the earth, and the geographical locations of these areas can be determined by the identification of the areas. Therefore, the network device can indicate the information of the area (such as indicating the total number of areas and/or the radius of the area) to the terminal device, so that the terminal device can obtain the distribution of the area based on the information of the area, thereby determining the area where the terminal device is located according to the location information of the terminal device and the distribution of the area, and performing mobility management based on the area where the terminal device is located. Compared with the network device directly configuring the reference point location information to the terminal device (such as sending the location coordinates of the reference point, etc.) to enable the terminal device to perform mobility management, the signaling overhead can be reduced.

In a possible design, the first information indicates the total number of areas N _spot and/or the radius R _spot of an area.

Based on this possible design, the terminal device can learn the total number of area identifiers, thereby learning the geographical location of each area according to the area identifier, and further learning the regional distribution.

In a possible design, the first information further indicates at least one of the following: an identifier of a reference area, elevation information, ephemeris information of a first network device, or ephemeris information of a second network device. The reference area is an area in a first cell, and the first cell is a cell managed by the first network device; the elevation information indicates a minimum elevation angle corresponding to the first cell, or indicates a minimum elevation angle corresponding to an area in the first cell.

In a possible design, mobility management is performed according to the identifier of the first area, including: determining a reference position in the first area according to the identifier of the first area; determining the remaining service time of the first cell according to the reference position in the first area, ephemeris information of the first network device, and the first elevation angle; before the remaining service time of the first cell ends, starting neighboring cell measurement. The first elevation angle is the minimum elevation angle corresponding to the first cell or the minimum elevation angle corresponding to the first area.

In a possible design, mobility management is performed according to the identifier of the first area, including: determining a reference position in the reference area according to the identifier of the reference area and the total number of areas; determining the remaining service time of the first cell according to the reference position in the reference area, the ephemeris information of the first network device, and the first elevation angle; before the remaining service time of the first cell ends, starting neighboring cell measurement. The first elevation angle is the minimum elevation angle corresponding to the first cell or the minimum elevation angle corresponding to the first area. The first cell is a cell managed by the first network device.

Based on the above two possible designs, since the terminal device starts neighboring cell measurement before the remaining service time of the first cell ends, and whether the first cell is covered is determined by the movement of the network device, this design can be applicable to the scenario where cell reselection is triggered by the movement of the first network device.

In a possible design, mobility management is performed according to the identifier of the first area, including: determining a reference position in the first area according to the identifier of the first area; and performing neighboring area measurement on the second network device within a first time window. The offset between the start time of the first time window and the reference time is the difference between the first delay and the second delay, and the first delay is the propagation delay between the reference position in the first area and the first network device. delay, and the second delay is a propagation delay between a reference location in the first area and the second network device.

Based on this possible design, the terminal device performs neighboring cell measurements within the first time window, and the starting time of the first time window is related to the propagation delay between the terminal device and the network device. Due to the movement of the network device, the network device may be located at different positions at different times, so that the propagation delay between the terminal device and the network device varies with time. Therefore, this design can be applicable to the scenario where cell reselection is triggered by the movement of the first network device.

In a possible design, the first information further indicates at least one of the following: an area pattern, an identifier of a reference area, or a first threshold. The area pattern indicates an identifier of at least one second area, where the second area is an area served by a beam of the first network device; the reference area is an area in the first cell, where the first cell is a cell managed by the first network device.

In one possible design, mobility management is performed according to the identifier of the first area, including: performing neighboring cell measurement when at least one of the following is met: the identifier of at least one second area does not include the identifier of the first area; or, the distance between the reference position in the first area and the reference position in the third area is greater than or equal to a first threshold, the reference position in the first area is determined according to the identifier of the first area, and the third area is an edge area of at least one second area; or, the distance between the reference position in the first area and the reference position in the reference area is greater than or equal to the first threshold; or, the difference between the identifier of the first area and the identifier of the reference area is greater than or equal to the first threshold; the distance between the position of the terminal device and the reference position in the third area is greater than or equal to the first threshold; or, the distance between the position of the terminal device and the reference position in the reference area is greater than or equal to the first threshold.

Based on this possible design, the condition for triggering neighbor cell measurement is related to the location of the terminal device, and when the terminal device is in different locations, the above conditions may be satisfied differently. Therefore, this solution can be applied to the scenario where the movement of the terminal device triggers cell reselection.

In one possible design, the first information also indicates the identifier of at least one fourth area and the access information corresponding to at least one fourth area, the fourth area is an area among N _spot areas that can be covered by the first network device, and the access information is used for the terminal device in the fourth area to access the second network device.

In one possible design, the access information includes at least one of the following: an identifier of the second network device, an identifier of a target beam, a random access resource, or a random access preamble code; the target beam is a beam of the second network device.

Based on the above two possible designs, the first network device can indicate the identifier of the fourth area and its corresponding access information to the terminal device, so that the terminal device in the fourth area can access other network devices according to the access information. In addition, the first network device can indicate different random access resources for different fourth areas, so that terminal devices in different fourth areas can access other network devices on different random access resources, reducing resource collisions when terminal devices perform random access, thereby improving access success rate.

In one possible design, the identifier of the fourth region and the access information corresponding to the fourth region are located in a subheader of a media access control MAC protocol data unit PDU; or, the identifier of the fourth region and the access information corresponding to the fourth region are located in a MAC control element CE of the MAC PDU; or, the identifier of the fourth region is located in a subheader of the MAC PDU, and the access information corresponding to the fourth region is located in the MAC CE of the MAC PDU.

In one possible design, mobility management is performed based on the identifier of the first area, including: determining whether the identifier of at least one fourth area includes the identifier of the first area; if the identifier of at least one fourth area includes the identifier of the first area, accessing the second network device according to the access information corresponding to the first area.

In one possible design, the total number of areas is the total number of areas where the second network device is effective, and/or the radius of the area is the radius of the area where the second network device is effective.

In one possible design, mobility management is performed based on an identifier of the first area, including: receiving second information from a second network device based on the identifier of the first area, the second information indicating access information corresponding to the first area, the access information being used for terminal devices in the first area to access the second network device; and accessing the second network device based on the access information corresponding to the first area.

Based on this possible design, the second network device can indicate the access information corresponding to each area, so that the terminal device in the area can access the second network device according to the access information. In addition, the second network device can indicate different random access resources for different areas, so that the terminal devices in different areas can access the second network device on different random access resources, reducing resource collisions when the terminal devices perform random access, thereby improving the access success rate.

In the second aspect, a communication method is provided, which can be executed by a first network device, or by a component of the first network device, such as a processor, a chip, or a chip system of the first network device, or by a logic module or software that can implement all or part of the functions of the first network device. The method includes: obtaining first information, the first information indicating information of a region, the region is fixed relative to the earth, and the geographical location of the region is determined by an identifier of the region; sending the first information to a terminal device. Among them, the technical effects brought about by the second aspect can refer to the technical effects brought about by the above-mentioned first aspect, and will not be repeated here.

In a possible design, the first information indicates the total number of areas N _spot and/or the radius R _spot of an area.

In one possible design, the first information further indicates at least one of the following: an identifier of the reference area, elevation information, The ephemeris information or the ephemeris information of the second network device. The reference area is an area in the first cell, and the first cell is a cell managed by the first network device; the elevation angle information indicates the minimum elevation angle corresponding to the first cell, or indicates the minimum elevation angle corresponding to the area in the first cell.

In a possible design, the first information further indicates at least one of the following: an area pattern, an identifier of a reference area, or a first threshold. The area pattern indicates an identifier of at least one second area, where the second area is an area served by a beam of the first network device; the reference area is an area in the first cell, where the first cell is a cell managed by the first network device.

In one possible design, the first information also indicates the identifier of at least one fourth area and the access information corresponding to at least one fourth area, the fourth area is an area among N _spot areas that can be covered by the first network device, and the access information is used for terminal devices in the fourth area to access the second network device.

In one possible design, the access information includes at least one of the following: an identifier of the second network device, an identifier of a target beam, a random access resource, or a random access preamble code; the target beam is a beam of the second network device.

In one possible design, the identifier of the fourth region and the access information corresponding to the fourth region are located in a subheader of a media access control MAC protocol data unit PDU; or, the identifier of the fourth region and the access information corresponding to the fourth region are located in a MAC control element CE of the MAC PDU; or, the identifier of the fourth region is located in a subheader of the MAC PDU, and the access information corresponding to the fourth region is located in the MAC CE of the MAC PDU.

In one possible design, the total number of areas is the total number of areas where the second network device is effective, and/or the radius of the area is the radius of the area where the second network device is effective.

Among them, the technical effects brought about by any possible design of the second aspect can refer to the technical effects brought about by the corresponding design in the above-mentioned first aspect, and will not be repeated here.

In combination with the first aspect or the second aspect, in a possible design, the geographical location of the region is also determined based on at least one of the following: the radius of the region, the radius of the earth, and the total number of regions.

Based on this possible design, the total number of regions, the radius of the region, and the radius of the earth can be the same for each region, that is, the total number of regions, the radius of the region, and the radius of the earth can be considered constants. At this time, the variable that affects the geographical location of the region can be considered to be the identifier of the region.

In combination with the first aspect or the second aspect, in a possible design, the region includes a reference position, and the three-dimensional coordinates of the reference position and the identifier of the region satisfy the following relationship:

Among them, i represents the identifier of the area, RL(i) represents the three-dimensional coordinates of the reference position, _Re represents the radius of the earth, [x] represents the decimal part of x, and N _spot represents the total number of areas.

In combination with the first aspect or the second aspect, in a possible design, the projection RL(x _i ,y _i ) of the reference position on the unit square and the identifier of the region satisfy the following relationship:
RL( _xi ) = (1 - _cosθi ) / 2

Wherein, the unit square refers to the square in the Cartesian plane with vertices at (0,0), (1,0), (0,1) and (1,1), RL( _xi ) represents the projection metric of the reference position on the x-axis of the unit square, and RL( _yi ) represents the projection metric of the reference position on the y-axis of the unit square.

In combination with the first aspect or the second aspect, in a possible design, the Cartesian coordinates RL (x _i , y _i ) of the reference position and the identifier of the region satisfy the following relationship:
RL( _xi )＝i/ _Nspot

Wherein, RL( _xi ) represents the projection measurement of the reference position in the x-axis direction of the Cartesian coordinate system, and RL( _yi ) represents the projection measurement of the reference position in the y-axis direction of the Cartesian coordinate system.

In combination with the first aspect or the second aspect, in a possible design, the region includes a reference position, and the three-dimensional coordinates of the reference position and the identifier of the region satisfy the following relationship:

Among them, i represents the identification of the area, RL(i) represents the three-dimensional coordinates of the reference position, Re represents the radius of the earth, and N _spot represents the total number of areas.

In combination with the first aspect or the second aspect, in a possible design, the region includes a reference position, and the latitude and longitude coordinates of the reference position and the identifier of the region satisfy the following relationship:
RL(i)＝(lon(i),lat(i))

Wherein, lon(i) represents the longitude of the reference location, lat(i) represents the latitude of the reference location, and N _spot represents the total number of areas.

In combination with the first aspect or the second aspect, in a possible design, the radius of the area and the total number of areas satisfy the following relationship:

Among them, _Re represents the radius of the earth, N _spot represents the total number of areas, and R _spot represents the radius of the area.

Based on the above possible designs, on the one hand, the coordinates of the reference position in the area can be quickly and accurately determined according to the identification of the area, so that the outline, geographical location, etc. of the area can be quickly and accurately determined. On the other hand, the radius of the area can be flexibly adjusted to adapt to different load capacities, such as adapting to different beam radii. On the other hand, since the geographical location of the area can be determined by the identification of the area, information exchange can be carried out between network devices and terminal devices based on the identification of the area. Compared with directly sending reference point location information for mobility management, the signaling overhead can be significantly reduced; compared with the division method based on the H3 geographic grid, since the total number of areas is relatively small, the number of bits required to indicate the area identification is also small, which can also reduce the signaling overhead.

In a third aspect, a communication device is provided for implementing various methods. The communication device may be the terminal device in the first aspect, or a device included in the terminal device, such as a chip or a chip system; or, the communication device may be the first network device in the second aspect, or a device included in the second network device, such as a chip or a chip system. The communication device includes a module, unit, or means corresponding to the implementation method, and the module, unit, or means may be implemented by hardware, software, or by hardware executing the corresponding software implementation. The hardware or software includes one or more modules or units corresponding to the functions.

In some possible designs, the communication device may include a processing module and a transceiver module. The processing module may be used to implement the processing function in any of the above aspects and any possible implementations thereof. The transceiver module may include a receiving module and a sending module, respectively used to implement the receiving function and the sending function in any of the above aspects and any possible implementations thereof.

In some possible designs, the transceiver module may be composed of a transceiver circuit, a transceiver, a transceiver or a communication interface.

In a fourth aspect, a communication device is provided, comprising: a processor and a memory; the memory is used to store computer instructions, and when the processor executes the instructions, the communication device executes the method described in any aspect. The communication device can be the terminal device in the first aspect, or a device included in the terminal device, such as a chip or a chip system; or the communication device can be the first network device in the second aspect, or a device included in the second network device, such as a chip or a chip system.

In a fifth aspect, a communication device is provided, comprising: a processor and a communication interface; the communication interface is used to communicate with a module outside the communication device; the processor is used to execute a computer program or instruction so that the communication device executes the method described in any aspect. The communication device can be the terminal device in the first aspect, or a device included in the terminal device, such as a chip or a chip system; or the communication device can be the first network device in the second aspect, or a device included in the second network device, such as a chip or a chip system.

In a sixth aspect, a communication device is provided, comprising: at least one processor; the processor is used to execute a computer program or instruction stored in a memory so that the communication device performs the method described in any aspect. The memory may be coupled to the processor, or may be independent of the processor. The communication device may be the terminal device in the first aspect, or a device included in the terminal device, such as a chip or a chip system; or the communication device may be the first network device in the second aspect, or a device included in the second network device, such as a chip or a chip system.

In a seventh aspect, a computer-readable storage medium is provided, in which a computer program or instruction is stored. When the computer-readable storage medium is run on a communication device, the communication device can execute the method described in the first aspect and any possible design thereof.

In an eighth aspect, there is provided a computer program product comprising instructions, which, when executed on a communication device, enables the communication device to Perform the method described in any aspect and any possible design thereof.

In a ninth aspect, a communication device (for example, the communication device may be a chip or a chip system) is provided, wherein the communication device includes a processor for implementing the functions involved in any aspect and any possible design thereof.

In some possible designs, the communication device includes a memory for storing necessary program instructions and data.

In some possible designs, when the device is a chip system, it can be composed of a chip or include a chip and other discrete devices.

It can be understood that when the communication device provided in any one of the third aspect to the ninth aspect is a chip, the sending action/function of the communication device can be understood as output information, and the receiving action/function of the communication device can be understood as input information.

Among them, the technical effects brought about by any design method in the third to ninth aspects can refer to the technical effects brought about by different design methods in the first or second aspects, and will not be repeated here.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of beam coverage in a non-staring mode and a staring mode in an NTN provided by the present application;

FIG2 is a schematic diagram of a projection of a beam on the ground provided by the present application;

FIG3 is a schematic diagram of a regional description method based on an H3 geographic grid provided by the present application;

FIG4 is a schematic diagram of a group switching scenario provided by the present application;

FIG5 is a schematic diagram of a cell switching process provided by the present application;

FIG6 is a satellite network architecture diagram in a transparent transmission mode provided by the present application;

FIG7 is a satellite network architecture diagram in a regeneration mode provided by the present application;

FIG8 is a diagram of a satellite network architecture in another regeneration mode provided by the present application;

FIG9 is a diagram of a satellite network architecture in another regeneration mode provided by the present application;

FIG10 is a network architecture diagram of NTN and terrestrial network integration provided by the present application;

FIG11 is a schematic diagram of a mapping relationship between beams and regions of a network device provided by the present application;

FIG12 is a flow chart of a communication method provided by the present application;

FIG13 is a flow chart of a communication method provided by the present application;

FIG14 is a schematic diagram of an elevation angle provided by the present application;

FIG15 is a flow chart of a communication method provided by the present application;

FIG16 is a schematic diagram of a propagation delay provided by the present application;

FIG17 is a schematic diagram of a terminal device movement provided by the present application;

FIG18 is a flow chart of a communication method provided by the present application;

FIG19 is a schematic diagram of a terminal switching scenario provided by the present application;

Figure 20 is a schematic diagram of the structure of a MAC PDU provided by this application;

FIG21 is a flow chart of a communication method provided by the present application;

FIG22 is a schematic diagram of a switching process provided by the present application;

FIG23 is a schematic diagram of the structure of a communication device provided by the present application;

FIG24 is a schematic diagram of the structure of another communication device provided by the present application;

FIG25 is a schematic diagram of the structure of another communication device provided in the present application.

DETAILED DESCRIPTION

In the description of this application, unless otherwise specified, "/" indicates that the objects associated with each other are in an "or" relationship, for example, A/B can represent A or B; "and/or" in this application is merely a description of the association relationship between associated objects, indicating that three relationships may exist, for example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural.

In the description of this application, unless otherwise specified, "plurality" means two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

In addition, in order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as "first" and "second" are used to distinguish the same items or similar items with substantially the same functions and effects. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit the difference.

In the embodiments of the present application, the words "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" should not be interpreted as being more preferred or advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner for ease of understanding.

It is understood that the "embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, the various embodiments in the entire specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It is understood that in various embodiments of the present application, the size of the sequence number of each process does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

It can be understood that in the present application, "when" and "if" both mean that corresponding processing will be carried out under certain objective circumstances, and do not limit the time, nor do they require any judgment action when implementing, nor do they mean the existence of other limitations.

It can be understood that some optional features in the embodiments of the present application may be implemented independently in certain scenarios without relying on other features, such as the solution on which they are currently based, to solve corresponding technical problems and achieve corresponding effects, or may be combined with other features according to needs in certain scenarios. Accordingly, the devices provided in the embodiments of the present application may also realize these features or functions accordingly, which will not be elaborated here.

In this application, unless otherwise specified, the same or similar parts between the various embodiments can refer to each other. In the various embodiments in this application, and the various implementation methods/implementation methods/implementation methods in each embodiment, if there is no special explanation and logical conflict, the terms and/or descriptions between different embodiments and the various implementation methods/implementation methods/implementation methods in each embodiment are consistent and can be referenced to each other. The technical features in different embodiments and the various implementation methods/implementation methods/implementation methods in each embodiment can be combined to form new embodiments, implementation methods, implementation methods, or implementation methods according to their inherent logical relationships. The implementation methods of this application described below do not constitute a limitation on the scope of protection of this application.

In order to facilitate understanding of the technical solutions of the embodiments of the present application, a brief introduction to the related technologies of the present application is first given as follows.

1. Non-terrestrial networks (NTN):

At present, the fifth generation (5G) new radio (NR) has entered the commercial deployment stage from the standardization stage. The NR standard is mainly designed for the characteristics of terrestrial communications, which can provide user terminals with high-speed, high-reliability, and low-latency communications.

Compared with terrestrial communications, NTN communications have significant advantages such as global coverage, long-distance transmission, flexible networking, convenient deployment and no geographical restrictions. They have been widely used in maritime communications, positioning navigation, disaster relief, scientific experiments, video broadcasting and earth observation. NTN networks can be integrated with terrestrial networks to complement each other and form a global seamless integrated communication network covering sea, land, air, space and ground to meet the various business needs of users everywhere.

According to the height of the flight platform from the ground, NTN can include a low altitude platform (LAP) subnetwork, a high altitude platform (HAP) subnetwork, and a satellite communication subnetwork (SATCOM subnetwork).

For example, in the LAP subnetwork, base stations or base station functions are deployed on low-altitude flying platforms (such as drones) 0.1km to 1km above the ground to provide coverage for terminals; in the HAP subnetwork, base stations or base station functions are deployed on high-altitude flying platforms (such as airplanes) 8km to 50km above the ground to provide coverage for terminals; in the SATCOM subnetwork, base stations or base station functions are deployed on satellites more than 50km above the ground to provide coverage for terminals.

Furthermore, according to the orbital altitude of the satellite, the satellite communication system can be divided into geostationary earth orbit (GEO) satellite communication system, medium earth orbit (MEO) satellite communication system and low-earth orbit (LEO) satellite communication system.

The GEO satellite communication system is also known as the synchronous orbit satellite system. The orbital altitude of the GEO satellite is 35786km, and its movement speed is the same as the rotation speed of the earth, that is, the GEO satellite can remain stationary relative to the ground. The GEO satellite communication system can provide large cell coverage, and the diameter of the cell is generally 500km. However, GEO satellite communication also has obvious disadvantages: 1) The GEO satellite orbit is far away from the earth, and the free space propagation loss is large, resulting in a tight communication link budget. In order to increase the transmission/reception gain, the satellite needs to be equipped with a larger diameter antenna; 2) The communication transmission delay is large, for example, there is a round-trip delay of about 500 milliseconds, which cannot meet the needs of real-time services; 3) GEO orbit resources are relatively tight, the launch cost is high, and it cannot provide coverage for the earth's polar regions.

The orbital altitude of MEO satellites is between 2000 and 35786 km, and global coverage can be achieved with a relatively small number of satellites. However, the orbital altitude of MEO satellites is higher than that of LEO satellites, and the transmission delay is still larger than that of LEO satellite communications. Therefore, considering the advantages and disadvantages of MEO satellite communications, MEO satellites are mainly used for positioning and navigation.

The orbital altitude of LEO satellites is between 300 and 2000 km, which is lower than that of MEO satellites. It has the advantages of small transmission delay, small transmission loss and relatively low launch cost.

The next generation of satellite communication systems generally presents a trend of ultra-dense and heterogeneous. First, the scale of satellites has grown from 66 in the Iridium constellation to 720 in the OneNet constellation, and eventually extended to the 12,000+ Starlink ultra-dense LEO satellite constellation; second, the satellite network presents heterogeneous characteristics, from the traditional single-layer communication network to the multi-layer communication network, the functions of the communication satellite network also tend to be complex and diversified, and gradually compatible with and support functions such as navigation enhancement, earth observation, and multi-dimensional information on-orbit processing.

2. Non-gazing mode (earth-moving) and gazing (earth-fixed or quasi-earth fixed) mode:

In satellite communication systems, according to the working mode of the beam, it can usually be divided into non-staring mode and staring mode. As shown in (a) of Figure 1, in the non-staring mode, the coverage of the satellite beam moves with the satellite for a period of time (such as between time t0 and time t2). As shown in (b) of Figure 1, in the staring mode, for a period of time (such as between time t0 and time t2), the satellite dynamically adjusts the beam pointing so that the beam approximately covers the same area on the ground. However, in actual applications, due to the accuracy of beam pointing and the distortion of beam projection on the ground at different incident angles, in the staring mode, the coverage area of the beam still has a certain degree of jitter as time changes.

Exemplarily, the embodiment of the beam in the protocol can be a spatial domain filter, or a spatial filter, or a spatial domain parameter, a spatial parameter, a spatial domain setting, a spatial setting, or quasi-colocation (QCL) information, a QCL assumption, a QCL indication, etc. The beam can be indicated by a transmission configuration indication (TCI) state (TCI-state) parameter, or by a spatial relation (spatial relation) parameter. Therefore, in this application, the beam can be replaced by a spatial filter, a spatial filter, a spatial parameter, a spatial parameter, a spatial setting, a spatial setting, QCL information, a QCL assumption, a QCL indication, TCI-state, a spatial relationship, etc. The above terms are also equivalent to each other. The beam in this application can also be replaced by other terms representing the beam, and this application is not limited.

3. Description of NTN’s service area:

As a first possible implementation, the service area of the satellite/cell can be characterized by calculating the corresponding contours of antenna gain or received power in different areas on the ground (which can be understood as the projection of the beam on the ground) based on the antenna pattern, such as a given antenna model. The contour can also be understood as the beam position.

For example, as shown in (a) of FIG2 , the antenna gain pattern of the beam reference system of a single GEO satellite 72 is shown. The ellipse represents the projection of the beam on the ground, or the beam position. As shown in (b) of FIG2 , the profile of the beam of the LEO satellite in the latitude and longitude plane in the non-staring mode is shown.

In the first possible implementation, since the projection of the beam on the ground is understood as the wave position, the wave position can be considered to be statically bound to the beam. Therefore, this solution is usually used in GEO satellite networks or satellite networks in non-staring mode. However, in the staring mode, the inclination angle between the satellite and a certain area of the ground changes dynamically, and the beam projection also changes accordingly. The solution of statically binding the wave position to the beam may no longer be applicable. In addition, since the projection of the beam on the ground is regarded as the wave position, parameters such as the beam reference point, the outline of the beam coverage area, and the satellite motion vector are usually required to determine the specific location of the wave position, which requires a large signaling overhead.

As a second possible implementation, the surface of the earth can be divided into regular pentagonal or regular hexagonal grids based on the H3 geographic grid, and the grid is used to represent the service area of the satellite/cell. For example, the service area of the satellite/cell may include one or more grids. Each grid can be understood as a wave position. Exemplarily, when the division is performed based on the H3 geographic grid, the earth is regarded as an icosahedron, each face of which is a spherical triangle with 12 vertices, which is called a spherical icosahedron. Each face of the spherical icosahedron has hexagons arranged in the same manner.

This second possible implementation supports hierarchical addressing of wave positions. Exemplarily, as shown in FIG3 , there are three types of regular hexagons of small, medium, and large areas, wherein the regular hexagon with the smallest area represents the wave position, and the regular hexagons of the remaining two areas can be used for hierarchical addressing of the wave position. For the convenience of description, the following embodiments refer to the regular hexagons with the largest area and the second largest area as the first regular hexagon and the second regular hexagon, respectively.

Based on the example shown in FIG3, when performing hierarchical addressing of wave positions, the index of the first regular hexagon can be understood as the first-level index of the wave position, the index of the second regular hexagon can be understood as the second-level index of the wave position, and the index of the regular hexagon with the smallest area can be understood as the third-level index of the wave position. When indexing a wave position, the first regular hexagon to which the wave position belongs can be first determined according to the first-level index, and then the second regular hexagon to which the wave position in the first regular hexagon belongs can be determined according to the second-level index, and finally the wave position in the second regular hexagon can be determined according to the third-level index.

In the second possible implementation, only 16 different precisions of the wave position radius are currently supported, which makes it difficult to adapt to different load capacities (such as beam radius). For example, when the precision of the wave position radius is an integer and the beam radius is not an integer, the wave position may not be accurately used to represent the service area of the satellite/cell. In addition, when determining the specific geographical location of the wave position based on the index value of the wave position in this scheme, it is usually necessary to determine it through an iterative loop, and the exact location of the wave position cannot be quickly calculated. Moreover, the index value of the wave position is usually indicated by 64 bits, and the signaling overhead is also large.

4. Group switching and group reselection:

The movement of the satellite may cause group switching of connected terminal devices in a certain area, or group reselection of idle terminal devices in the area.

Taking group handover as an example, as shown in FIG4 , it is assumed that there is a UE cluster (referred to as UE-G1, which includes multiple UEs) in sub-area 1 of area 2. At time T1, the sub-area 1 is served by one or more beams of satellite 2. At time T2, the movement of satellite 2 causes satellite 2 to be unable to continue to serve sub-area 1, and one or more beams of satellite 1 take over satellite 2 to serve sub-area 1. In this process, since the satellite covering sub-area 1 changes, multiple UEs in UE-G1 undergo group handover, switching from satellite 2 to satellite 1.

Since the satellite moves at a relatively high speed, for example, the speed of a LEO satellite is about 7.5 km/s, the frequency of group switching is relatively high, about once every several seconds to several tens of seconds.

5. Mobility Management:

Mobility management mainly includes cell switching, cell reselection, registration update and tracking area update. Taking cell switching as an example, as shown in Figure 5, the cell switching process in the NR system mainly includes the following steps:

1) Cell handover measurement: The source base station (such as the next generation node B (gNodeB or gNB)) can send measurement configurations of multiple cells (including serving cells and neighboring cells) to the terminal device. The terminal device measures the cell signal quality according to the measurement configuration. Exemplarily, the cell signal quality can be represented by reference signal receiving power (RSRP) and/or reference signal receiving quality (RSRQ).

2) Measurement result reporting: The terminal device reports the measurement result to the source base station. For example, the terminal device can report periodically or based on event triggering. For example, the reporting triggering event can be that the signal quality of the serving cell is less than threshold 1, and/or the signal quality of the neighboring cell is greater than threshold 2.

3) Handover decision: The source base station selects a suitable neighboring cell as the target cell based on the measurement results, and sends a handover request to the target base station, which carries context information related to the user handover.

4) Admission control: After receiving the handover request, the target base station performs admission control. If the terminal device is allowed to access, it sends a handover request confirmation message to the source base station, which carries relevant information for the terminal device to access the target cell. After receiving the handover request confirmation message, the source base station sends a radio resource control (RRC) reconfiguration message to the terminal device, which carries relevant information for accessing the target cell.

5) Handover execution: After receiving the handover-related information, the terminal device completes the access process in the target cell.

Exemplarily, the terminal device sends a random access preamble to the target cell to initiate random access in the target cell. The random access preamble used by the terminal device during the handover process is a dedicated preamble, which is different from the contention-based random access preamble during initial access. In addition, the period of the random access channel (RACH) configured by the network during cell handover can be 10/20/40/80/160 milliseconds (ms).

During the cell reselection process, the base station sends neighboring cell-related measurement configuration and other parameters in broadcast form. The terminal device compares the signal quality measurement value with the parameters sent by the network (such as the reselection threshold, etc.), and autonomously reselects to the target neighboring cell if the reselection conditions are met.

That is to say, in the NR system, the terminal device performs cell switching or cell reselection based on signal quality. However, the near-far effect is not obvious in NTN, and the efficiency of cell switching or cell reselection based only on signal quality is low. Therefore, NTN proposes to implement mobility management under the NTN network based on information such as time and location (such as the distance between the terminal device and the reference point of the source cell and the reference point of the target cell).

However, mobility management based on location and other information is designed for cell switching/reselection triggered by the movement of terminal devices. When this solution is applied to the group switching/group reselection scenario triggered by satellite movement, it will lead to frequent configuration information updates. For example, the network needs to frequently update the reference point location information of the cell, resulting in a large signaling overhead for mobility-related configuration on the network side.

Based on this, the present application provides a communication method. In this method, the ground can be discretized into some fixed areas relative to the earth, and the geographical locations of these areas can be determined by the identification of the areas. Therefore, the network device can indicate the information of the area (such as indicating the total number of areas and/or the radius of the area) to the terminal device, so that the terminal device can obtain the distribution of the area based on the information of the area, thereby determining the area where the terminal device is located according to the location information of the terminal device and the distribution of the area, and performing mobility management based on the area where the terminal device is located. Compared with the network device directly configuring the reference point location information to the terminal device (such as sending the location coordinates of the reference point, etc.) so that the terminal device can perform mobility management, the signaling overhead can be reduced.

The technical solution of the embodiment of the present application can be used for NTN systems such as satellite communication systems, high altitude platform station (HAPS) communication, and drones. For example, integrated communication and navigation (IcaN) systems, global navigation satellite systems (GNSS), etc. NTN systems can be integrated with traditional mobile communication systems. For example: the mobile communication system can be a fourth generation (4G) communication system (for example, a long term evolution (LTE) system), a worldwide interoperability for microwave access (WiMAX) communication system, a 5G communication system (for example, a NR system), a device-to-device (D2D) communication system, a machine-to-machine (M2M) communication system, an Internet of Things (IoT) communication system, an Internet of Vehicles communication system, and future mobile communication systems.

Among them, the above-mentioned communication system applicable to the present application is only an example, and the communication system and communication scenario applicable to the present application are not limited to this. The communication system and communication scenario provided by the present application do not impose any limitation on the scheme of the present application. They are uniformly explained here and will not be repeated below.

As a possible implementation, a communication system applicable to the solution of the present application may include at least one terminal device and at least one network device. Exemplarily, terminal devices and terminal devices, terminal devices and network devices, and network devices and network devices may communicate with each other in a wired or wireless manner.

Optionally, the terminal device may be a user-side device with wireless transceiver functions, or may be a chip or chip system provided in the device. The terminal device may also be referred to as user equipment (UE), terminal, access terminal, user unit, user station, mobile station (MS), remote station, remote terminal, mobile terminal (MT), user terminal, wireless communication device, user agent or user device, etc. The terminal device may be, for example, a terminal device in IoT, V2X, D2D, M2M, 5G network, or a future evolved public land mobile network (PLMN). The terminal device may be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; it may also be deployed on the water (such as ships, etc.); it may also be deployed in the air (such as airplanes, balloons and satellites, etc.).

Exemplarily, the terminal device can be a drone, an IoT device (e.g., a sensor, an electric meter, a water meter, etc.), a V2X device, a station (ST) in a wireless local area network (WLAN), a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA) device, a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device (also called a wearable smart device), a tablet computer or a computer with wireless transceiver function, a virtual reality (VR) device, or a wearable device. The invention relates to wireless terminals for use in the smart grid, transportation safety, smart cities, smart homes, in-vehicle terminals, vehicles with vehicle-to-vehicle (V2V) communication capabilities, intelligent networked vehicles, drones with unmanned aerial vehicle (UAV) to UAV (UAV to UAV, U2U) communication capabilities, etc. The terminal device can be mobile or fixed, and this application does not make specific restrictions on this.

Optionally, the network device may be a network-side device with wireless transceiver functions, or may be a chip or chip system or module provided in the device. The network device is located in the radio access network (RAN) of the mobile communication system and is used to provide access services for terminal devices.

As a possible implementation, the network device may be a wireless relay node or a wireless backhaul node. For example, the network device may be a layer 1 relay device for regenerating physical layer signals (i.e., processing of wireless frequency filtering, frequency conversion, and amplification) without other higher protocol layers.

As another possible implementation, the network device can implement part or all of the functions of a base station. For example, the network device can be an evolutionary Node B (eNB or eNodeB) in an LTE or an evolved LTE system (LTE-Advanced, LTE-A), such as a traditional macro base station eNB and a micro base station eNB in a heterogeneous network scenario; or it can be a next generation node B (gNodeB or gNB) in a 5G system; or it can be a transmission reception point (TRP); or it can be a base station in a future evolved PLMN; or it can be a device that implements base station functions in IoT, V2X, D2D, or M2M.

Alternatively, the network device may be a central unit (CU), a distributed unit (DU), a CU and a DU, a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The CU and the DU may be separately configured or may be included in the same network element, such as a baseband unit (BBU). The RU may be included in a radio frequency device or a radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, the network device may be a network device or a module of a network device in an open radio access network (open RAN, ORAN) system. In the ORAN system, CU may also be referred to as open (open, O)-CU, DU may also be referred to as O-DU, CU-CP may also be referred to as O-CU-CP, CU-UP may also be referred to as O-CU-UP, and RU may also be referred to as O-RU. Any of the CU (or CU-CP, CU-UP), DU and RU in this application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

Exemplarily, the base stations in the embodiments of the present application may include various forms of base stations, such as: macro base stations, micro base stations (also called small stations), relay stations, access points, etc., and the embodiments of the present application do not specifically limit this.

Optionally, the network device in the embodiment of the present application can be deployed on a non-ground platform, for example, deployed on a low-altitude platform (such as a drone), a high-altitude platform (such as an airplane), or a satellite. Therefore, the network device in the embodiment of the present application can also be referred to as a non-ground network device.

For example, taking the case where the network device is deployed on a satellite, or the network device is a satellite, the communication system may also include an NTN network. NTN gateway (or gateway station). Usually, NTN gateway is deployed on the ground. NTN gateway can communicate with satellite, and the link between satellite and NTN gateway can be called feeder link.

As shown in Figure 6, when the satellite is used as a wireless relay node, or the satellite has a relay forwarding function, the NTN gateway has the function of a base station or part of the base station function, and the NTN gateway can be used as a base station. Alternatively, the NTN gateway can be deployed separately from the base station, that is, in addition to the NTN gateway, the communication system also includes a satellite base station deployed on the ground. Figure 6 takes the NTN gateway and the base station as an example for explanation.

As shown in Figure 7, when the satellite can realize part or all of the functions of the base station, the satellite has data processing capabilities and can be used as a base station. At this time, the NTN gateway and the satellite can transmit the user plane data of the terminal device through the satellite radio interface (SRI).

In addition, in the case where the satellite can realize part or all of the functions of the base station, as shown in Figure 8, there is an inter-satellite link (ISL) between different satellites, and the satellites can communicate through the ISL. Alternatively, as shown in Figure 9, the satellite can have the DU processing function of the base station, or the satellite can act as a DU. In this scenario, the CU processing function of the base station can be deployed on the ground, and the CU and DU communicate using the F1 interface through the NTN gateway.

In the architectures shown in FIGS. 6 to 9 , NG refers to the interface between the base station and the core network. Uu refers to the interface between the base station and the terminal device. Xn refers to the interface between base stations. It is understandable that, with the evolution of the communication system, the interface name between the base station and the core network, the interface name between the base station and the terminal device, and the interface name between the base stations may also change, and this application does not specifically limit this.

Optionally, when a satellite acts as a wireless relay node and has a relay forwarding function, the satellite can be considered to be operating in a transparent mode. When a satellite has data processing capabilities and can realize some or all of the functions of a base station, the satellite can be considered to be operating in a regenerative mode. For a certain satellite, it can support only the transparent mode or only the regenerative mode, or it can support both the transparent mode and the regenerative mode, and can switch between the transparent mode and the regenerative mode.

In some implementation scenarios, NTN and the ground network can be integrated. Exemplarily, FIG10 is a diagram of the integrated network architecture of NTN and the ground network provided in an embodiment of the present application. In the architecture shown in FIG10, satellite 1 and satellite 2 work in regeneration mode, and the satellites can be used as NTN base stations, or NTN base stations can be deployed on satellites. Satellite 3 works in transparent transmission mode, so additional NTN base stations need to be deployed. Among them, NTN base stations refer to base stations in NTN. In addition,

In addition, the architecture may also include ground base stations, which refer to base stations in the ground network. NTN base stations and ground base stations can be interconnected through a common core network. As a bearer network, the core network provides an interface to the data network, provides communication connection, authentication, management, policy control for terminal devices, and completes the bearing of data services. Exemplarily, the core network may include access and mobility management function (AMF) network elements, session management function (SMF) network elements, authentication server function (AUSF) network elements, policy control function (PCF) network elements, user plane function (UPF) network elements, and other network elements.

Alternatively, the NTN base station and the ground base station can also achieve more timely assistance and interconnection through the interface defined between the base stations. Exemplarily, the interface between the base stations can be an Xn interface, and the interface between the base station and the core network can be an NG interface. Of course, the interface between the base stations and the interface between the base station and the core network can also be implemented in other ways, which are not specifically limited in this application.

Optionally, in an embodiment of the present application, the satellite can provide services to the terminal device through a beam. For example, different beams can provide services to the terminal device through one or more of time division, frequency division and space division. On the one hand, the satellite can operate in a regeneration mode or a transparent transmission mode. On the other hand, the satellite can operate in a non-staring mode or a staring mode. The satellite can be a LEO satellite, a MEO satellite, a GEO satellite, etc., without limitation.

It is understandable that the satellites in the architectures described in Figures 6 to 10 above can be replaced by ground payloads on other flying platforms such as drones and airplanes.

It should be noted that the communication system described in the embodiment of the present application is for the purpose of more clearly illustrating the technical solution of the embodiment of the present application, and does not constitute a limitation on the technical solution provided in the embodiment of the present application. A person of ordinary skill in the art can know that with the evolution of network architecture and the emergence of new business scenarios, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

The following describes the communication method provided in the embodiment of the present application by taking the interaction between a network device and a terminal device as an example in combination with the communication system shown in Figures 6 to 10.

It should be noted that in the following embodiments of the present application, the message names between the devices, the names of the parameters, or the names of the information are only examples. In other embodiments, they may also be other names, and the method provided in the present application does not make any specific limitations on this.

It is understandable that in the embodiments of the present application, the execution subject may execute some or all of the steps in the embodiments of the present application, and these steps or operations are only examples. The embodiments of the present application may also execute other operations or variations of various operations. In addition, the various steps may be executed in different orders presented in the embodiments of the present application, and it is possible that not all operations in the embodiments of the present application need to be executed.

As an example, in the following embodiments, the above-mentioned flying platform is a satellite, that is, satellite communication in NTN is taken as an example for description. Of course, this method can also be applied to other scenarios in the NTN, such as LAP subnetwork or HAP subnetwork, and is not specifically limited thereto.

In order to facilitate understanding of the technical solutions of the embodiments of the present application, a brief introduction to the relevant terms in the present application is first given as follows.

1. Region:

Unless otherwise specified, the "region" in the following embodiments of the present application refers to a geographical region. The region is fixed relative to the earth, or it is understood that the region refers to a geographical region fixed relative to the earth. Exemplarily, the region can have at least one of the following attributes: shape, outline, size, radius, area, geographical location, etc.

"Region" can also have a height attribute, that is, the region can be understood as a geographical area of a given height or height range. By default, the region can refer to a geographical area with an altitude of 0 kilometers (km) above the ground or an altitude of about 0km (such as in the range of [-2, 2]km), or a geographical area with an average altitude. In addition, it can also refer to geographical areas of other specific heights or specific altitude ranges, such as a geographical area with an altitude of 10km, or a geographical area with an altitude of about 10km (such as in the range of [7, 13]km).

In a possible implementation, the above-mentioned region fixed relative to the earth may also be called a "wave position", "broadcast wave position", "geographical region", etc. Of course, there may be other names, and the present application does not specifically limit the name of the region fixed relative to the earth.

The shapes, outlines, sizes, radii, and areas of different regions may be the same or different. Different regions may have different geographical locations. Different regions may or may not overlap.

In a possible implementation, the region is fixed relative to the earth, which can be understood as: the outline, size or geographical location of the region remains unchanged, for example, the outline, size or geographical location of the region does not change with time. Alternatively, the region is fixed relative to the earth, which can be understood as: the outline of the region and the points in the region can be described by a three-dimensional coordinate system such as earth-centered earth-fixed (ECEF) coordinates, geodetic coordinate system, earth-centered inertial (ECI) coordinate system, or the coordinates of each point on the outline of the region in a three-dimensional coordinate system such as ECEF, geodetic coordinate system, ECI coordinate system, etc. are fixed and unchanged.

In a possible implementation, the shape of the region may be a regular hexagon, or other shapes such as a regular pentagon, a circle, an ellipse, etc. Alternatively, the shape of the region may also be an irregular shape, which is not limited.

Exemplarily, the shape of the area may be defined by a protocol or may be defined by a network device. The shapes of the areas defined by different network devices may be the same or different. The same network device may also define multiple shapes of areas. Similarly, the size, radius, and area of the area may be defined by a protocol or may be defined by a network device. The size, radius, and area of the areas defined by different network devices may be the same or different. The same network device may also define multiple area sizes, multiple area radii, or multiple area areas.

In a possible implementation, the earth may be divided into multiple regions, and the multiple regions may be indexed (eg, numbered).

As a possible division method, the geographical location of the region is determined by the identifier of the region, that is, the geographical location of the region can be obtained according to the identifier of a region, or in other words, there is a correlation between the identifier of the region and the geographical location of the region. For example, multiple regions can be discretized on the earth, each region corresponds to an identifier, and the geographical location of the region can be obtained according to the identifier of the region.

Furthermore, the geographical location of the area may also be determined according to at least one of the following: the total number of areas N _spot , the radius of the area R _spot , or the radius of the earth _Re .

Exemplarily, the total number of regions can be understood as the total number of regions discretely located on the earth. The N _spot regions can completely cover the earth, such as any location on the earth belongs to a certain region; or, the N _spot regions can also cover some geographical locations on the earth, for example, the _{N spot} regions may not cover the South Pole and/or the North Pole of the earth, that is, the South Pole and/or the North Pole may not exist in the region. N _spot is a positive integer, for example, N _spot =78702.

Exemplarily, the radii of the N _spot areas may be the same, that is, the radius of each area is R _spot . When the shape of the area is a regular hexagon, the radius of the area may be the radius of the circumscribed circle of the regular hexagon; when the shape of the area is a circle, the radius of the area may be the radius of the circle; when the shape of the area is an ellipse, the radius of the area may include a long radius or a short radius. The unit of R _spot may be kilometers (km), for example, R _spot = 50 kilometers, or may be other length units such as meters (m), without limitation.

Exemplarily, in an embodiment of the present application, the radius of the earth may be a constant, such as a value of 6378 km; or, the radius of the earth may be different for different time and space positions, for example, the radius of the earth may include an equatorial radius or a polar radius. For example, when dividing regions at the South Pole and/or the North Pole, the polar radius may be used; when dividing regions in non-polar regions, the equatorial radius may be used. Alternatively, when an ellipsoid is used to describe the earth (i.e., the shape of the earth is considered to be an ellipsoid), the radius of the earth may include a major axis and a minor axis, and there are differences in the values of the major axis and the minor axis.

As a possible implementation, the total number of regions, the radius of the region, and the radius of the earth may be the same for each region, that is, the total number of regions, the radius of the region, and the radius of the earth may be considered constants. In this case, the variable affecting the geographical location of the region may be considered to be the identifier of the region.

In a possible implementation, each region includes (or has) a reference position, which may be, for example, the center position of the region. Exemplarily, the geographic location of a region may refer to the geographic location of the reference position in the region. In this case, the geographic location of the region is determined by the identifier of the region, which may be understood as follows: the reference position in the region is determined by the identifier of the region; or the geographic location of the region may be To represent the outline of the area or the range of the area, at this time, the geographical location of the reference position in the area can be determined according to the identification of the area, and then the range or outline of the area can be determined according to the geographical location of the reference position and the radius of the area.

As a possible implementation, the association relationship between the reference position in the region and the identification of the region is determined according to the Fibonacci criterion, or in other words, the association relationship between the reference position in the region and the identification of the region satisfies the Fibonacci criterion. Exemplarily, there are the following three implementations of the association relationship:

Method 1: The three-dimensional coordinates of the reference position in the region and the identifier of the region satisfy the following relationship (1):

Wherein, i represents the identifier of the area. _Re represents the radius of the earth. [x] represents the decimal part of x, such as x=2.3, then [x]=0.3. N _spot represents the total number of areas. RL(i) represents the three-dimensional coordinates of the reference position in the area, and the three-dimensional coordinates refer to the coordinates in the three-dimensional coordinate system. Exemplarily, the three-dimensional coordinate system can be a spherical coordinate system, such as the ECEF coordinate system. Of course, it can also be other three-dimensional coordinate systems, such as the geodetic coordinate system, the earth-centered inertial (ECI) coordinate system, etc.

Exemplarily, the projection RL(x _i ,y _i ) of the reference position on the unit square and the identifier of the region satisfy the following relationship:
RL( _xi ) = (1 - _cosθi ) / 2

Among them, θ _i and Please refer to the above related instructions. The unit square refers to the square in the Cartesian plane with vertices at (0,0), (1,0), (0,1) and (1,1). RL( _xi ) represents the projection measurement of the reference position in the x-axis direction of the unit square, and RL( _yi ) represents the projection measurement of the reference position in the y-axis direction of the unit square.

Exemplarily, the Cartesian coordinates RL (x _i , y _i ) of the reference position in the Fibonacci grid and the identifier of the region satisfy the following relationship:
RL( _xi )＝i/ _Nspot

Wherein, [x] represents the fractional part of x. RL( _xi ) represents the projection measurement of the reference position of the region in the x-axis direction in the Cartesian coordinate system, and RL( _y ) represents the projection measurement of the reference position of the region in the y-axis direction in the Cartesian coordinate system. Exemplarily, the Cartesian coordinate system refers to the Cartesian rectangular coordinate system.

Method 2: The three-dimensional coordinates of the reference position in the region and the identifier of the region satisfy the following relationship (2):

The physical meaning of each parameter can be found in the relevant description in the above relationship (1), which will not be repeated here.

It can be understood that the three-dimensional coordinates of the reference positions shown in the above relationship (1) and relationship (2) can be equivalently converted into longitude and latitude positions, and the present application does not limit the specific form of expression of the reference positions.

Method 3: The latitude and longitude coordinates of the reference position in the region and the identifier of the region satisfy the following relationship (3):
RL(i)＝(lon(i),lat(i)) (3)

Where RL(i) represents the latitude and longitude coordinates of the reference location, such as lon(i) represents the longitude of the reference location, and lat(i) represents the latitude of the reference location. N _spot represents the total number of areas.

It can be understood that the latitude and longitude coordinates of the reference position shown in the above relationship (3) can be equivalently converted into three-dimensional coordinates. The specific form of the setting is not limited.

As a possible implementation, the radius of the region and the total number of regions satisfy the following relationship (4):

Among them, _Re represents the radius of the earth, N _spot represents the total number of areas, and R _spot represents the radius of the area. The explanation of each parameter can refer to the above related description, which will not be repeated here.

Based on the above possible designs, on the one hand, the coordinates of the reference position in the area can be quickly and accurately determined according to the identification of the area, so that the outline, geographical location, etc. of the area can be quickly and accurately determined. On the other hand, the radius of the area can be flexibly adjusted to adapt to different load capacities, such as adapting to different beam radii. On the other hand, since the geographical location of the area can be determined by the identification of the area, information exchange can be carried out between network devices and terminal devices based on the identification of the area. Compared with directly sending reference point location information for mobility management, the signaling overhead can be significantly reduced; compared with the division method based on the H3 geographic grid, since the total number of areas is relatively small, the number of bits required to indicate the area identification is also small, which can also reduce the signaling overhead.

2. Coverage area of network equipment:

The coverage area of a network device may refer to a maximum area that the network device can cover, or in other words, the coverage area of the network device indicates (or reflects) the maximum coverage capability of the first network device.

The coverage area of the network device changes with the movement of the network device, that is, the coverage area of the network device may be different at different times. The coverage area of the network device includes at least one of the above areas (ie, wave positions).

Since the coverage area of the network device changes with the movement of the network device, and the area (wave position) is fixed relative to the earth, the wave positions included in the coverage area of the network device may be different at different times.

For example, taking the shape of the area as a regular hexagon, as shown in Figure 11, the solid ellipse line can represent the coverage area of the network device. The areas represented by all the regular hexagons in the solid ellipse line are the areas included in the coverage area of the network device.

3. Service area of network equipment:

The service area of a network device may refer to the maximum area that a beam of the network device can serve (or cover), or in other words, the service area of the network device indicates (or reflects) the maximum service capability of the first network device.

The service area of the network device is smaller than or equal to the coverage area of the network device. Exemplarily, based on the example shown in FIG11 , the service area of the first network device may be the range indicated by the solid ellipse, in which case the service area of the first network device is equal to the coverage area of the first network device; or the service area of the first network device may also be smaller than the range indicated by the solid ellipse.

The service area of the network device changes with the movement of the network device, that is, the service area of the network device may be different at different times. The service area of the network device includes at least one of the above areas (ie, wave positions).

Since the service area of a network device changes with the movement of the network device, and the area (wavelength) is fixed relative to the earth, the wavelengths included in the service area of the network device may be different at different times.

In addition, at a certain moment, the beam of the network device may actually serve (or cover) a part of the service area, and at different moments, the beam of the network device may serve (or cover) different areas in the service area. For example, as shown in (a) of FIG. 11 , at time T1, the beam of the network device serves areas x1, x2, and x3 in the service area; as shown in (b) of FIG. 11 , at time T2, the beam of the network device serves areas y1, y2, y3, and y4 in the service area.

4. Activation area of network equipment:

The area currently being served (or covered) by the beam of the network device may be referred to as an activated area, or an activated area. The area currently not being served (or covered) by the beam of the network device may be referred to as an inactivated area, or an inactivated area.

The communication method provided in the embodiment of the present application is introduced below. Referring to FIG. 12 , which is a flow chart of a communication method provided in the embodiment of the present application, the communication method may include the following steps:

S1201. A first network device obtains first information.

The first information indicates information of the region. The region is fixed relative to the earth. The geographical location of the region is determined by the identifier of the region. Please refer to the above description of the region, which will not be repeated here.

In a possible implementation, the information of the first information indicating the area can be understood as: the first information indicating the division or distribution of the area. For example, the first information indicates the total number of areas N _spot and/or the radius of the area R _spot . The total number of areas and the radius of the area can refer to the above description of the area, which will not be repeated here.

Exemplarily, the total number of areas and/or the radius of an area can be understood as the total number of areas and/or the radius of an area that are effective or used by a first network device; or, it can be the total number of areas and/or the radius of an area that are effective or used by a second network device. The second network device can be an adjacent network device to the first network device. The total number of areas and/or the radius of an area that are effective or used by different network devices can be the same or different, without limitation.

Exemplarily, when the total number of areas is known, the identification of the area can be obtained, for example, the area identification belongs to 1, 2, ..., N _spot , and the geographical location of each area can be obtained based on the identification of each area. For example, the identification of the area and its reference position satisfy one of the above-mentioned relationships (1) to (3), so that the geographical location of N _spot areas can be known, that is, the distribution of the areas can be known.

In addition, when the radius of the region is known, the total number of regions can be determined based on the relationship between the radius of the region and the total number of regions, such as the above relationship (4), and then the geographical location of each region can be determined based on the region identification, thereby determining the distribution of the regions.

Exemplarily, the first information may include specific values of the total number of areas N _spot and/or the radius of the area R _spot . Alternatively, the protocol may predefine multiple total numbers of areas, or the network device and the terminal device may pre-negotiate multiple total numbers of areas. In this scenario, the first information may include an index of the total number of areas, which corresponds to one of the multiple total numbers of areas. For example, a total number of N areas is defined, and the first information may include an index n, n∈1,2,…,N, then the total number of areas indicated by the first information is the total number of n-th areas in the total number of N areas.

In a possible implementation, when the first information indicates the total number of areas and/or the radius of the areas in which the first network device is effective, the first network device obtains the first information, which may include: the first network device determines or generates the first information; or, the first network device receives the first information, for example, the first network device receives the first information from a ground device, that is, the first information is generated by the ground device and sent to the first network device.

Exemplarily, when the first network device is a device deployed on a satellite and has some or all base station functions, the first network device determines or generates the first information. When the first network device is deployed on a satellite and works in a transparent transmission mode, the first network device receives the first information from a core network element or an NTN base station deployed on the ground.

In another possible implementation, when the first information indicates the total number of areas and/or the radius of the areas where the second network device is effective, the first network device acquiring the first information may include: the first network device receiving the first information from the second network device.

S1202: The first network device sends first information to the terminal device. Correspondingly, the terminal device receives the first information from the first network device.

Exemplarily, the first network device may send the first information in a broadcast manner. For example, the first network device sends cell system information, and the system information carries the first information. Alternatively, the first network device may send the first information to a terminal device in a unicast manner, which is not specifically limited in this application.

It can be understood that when the first network device sends the first information by broadcasting, any terminal device in the cell can implement or execute the function implemented by the terminal device in the method provided in the embodiment of the present application.

S1203: The terminal device determines an identifier of a first area according to the location information of the terminal device and the first information, wherein the first area is an area where the terminal device is located.

Exemplarily, the location information of the terminal device may be GNSS location information of the terminal device. The first area may be an area in which the reference location is closest to the terminal device among the N _spot areas indicated by the first information.

Exemplarily, when the first information indicates the total number of areas N _spot and/or the radius of the area R _spot , after receiving the first information, the terminal device can obtain the total number of areas N _spot , and thus can obtain the identification of the area, for example, the area identification belongs to 1, 2, ..., N _spot . Based on the identification of each area, the geographical location of the reference position in each area can be obtained, for example, the identification of the area and its reference position satisfy one of the above-mentioned relationships (1) to (3), so that the distance between the terminal device and the reference position in each area can be obtained, and then the area to which the reference position closest to the terminal device belongs is determined as the first area.

S1204: The terminal device performs mobility management according to the identifier of the first area.

Exemplarily, the mobility management may include at least one of the following: neighboring cell measurement, cell reselection, cell switching, etc. Of course, the mobility management may also include other implementations, which are not specifically limited in the present application.

Based on the above scheme, the ground can be discretized into some fixed areas relative to the earth, and the geographical locations of these areas can be determined by the identification of the areas. Therefore, the network device can indicate the information of the area (such as indicating the total number of areas and/or the radius of the area) to the terminal device, so that the terminal device can obtain the distribution of the area based on the information of the area, thereby determining the area where the terminal device is located according to the location information of the terminal device and the distribution of the area, and performing mobility management based on the area where the terminal device is located. Compared with the network device directly configuring the reference point location information to the terminal device (such as sending the location coordinates of the reference point, etc.) so that the terminal device can perform mobility management, the signaling overhead can be reduced.

The above describes the overall process of the communication method provided in the embodiment of the present application. The following describes in detail the implementation of mobility management of the terminal device. Exemplarily, the terminal device can perform mobility management in the following five ways:

Method 1: As shown in FIG13 , the terminal device performs mobility management according to the identifier of the first area, including:

S120411. The terminal device determines a reference position in the first area according to an identifier of the first area.

Exemplarily, the identifier of the first area and the reference position in the first area may satisfy at least one of the above relationships (1) to (3). Please refer to the above related descriptions and will not be repeated here.

S120412. The terminal device determines the remaining service time of the first cell based on the reference position in the first area, the ephemeris information of the first network device, and the first elevation angle.

As a possible implementation, the first elevation angle is the minimum elevation angle corresponding to the first cell. The elevation angle at the reference position in each area of the first cell is greater than or equal to the first elevation angle. The first cell is a cell managed by the first network device, and the first cell may be a current service cell of the terminal device.

As another possible implementation, the first elevation angle is a minimum elevation angle corresponding to the first area. When the elevation angle is greater than or equal to the first elevation angle, the first area is completely covered by the first network device.

Exemplarily, for a certain position on the earth, when the line of sight is above the horizontal line, the angle between the line of sight and the horizontal line in the vertical plane where the line of sight is located can be understood as the elevation angle. In this form 3, the elevation angle at the reference position can be understood as the angle between the line between the reference position and the position of the first network device and the horizon at the reference position. The elevation angle at the reference position can be used to describe the position of the first network device passing above the reference position. For example, the elevation angle at the reference position is 90°, indicating that the first network device is located directly above the reference position.

As shown in (a) of FIG. 14 , the elevation angle when the reference position is at point P is shown; as shown in (b) of FIG. 14 , the elevation angle when the reference position is at point Q is shown.

As a possible implementation, the ephemeris information of the first network device describes the expression of the position and speed of the first network device that changes with time. Of course, the ephemeris information can also have other names, such as trajectory information, speed trajectory information, etc., which are not specifically limited in this application.

Exemplarily, the reference position in the first area, the ephemeris information of the first network device, the first elevation angle γ ₀ , and the remaining service time T _c of the first cell may satisfy the following relationship:
T _c =1/w×arccos(cos(γ ₀ )/cos(γ _m ))

Wherein, w is the angular velocity of the first network device in a three-dimensional coordinate system (such as the geocentric inertial coordinate system ECI), and _γm can be calculated based on a reference position in the first area and the ephemeris information of the first network device.

S120413. The terminal device starts neighbor cell measurement before the remaining service time of the first cell ends.

Exemplarily, if the starting time of the remaining service time of the first cell is t1 and the ending time is t2, then the terminal device starts the neighboring cell measurement before time t2.

As a possible implementation, starting the neighboring cell measurement can also be understood as executing the neighboring cell measurement. The neighboring cell measurement result can be used by the terminal device to perform cell reselection.

Mode 2, as shown in FIG15 , the terminal device performs mobility management according to the identifier of the first area, including:

S120421. The terminal device determines a reference position in the first area according to the identifier of the first area. Please refer to the relevant description in the above step S120411, which will not be repeated here.

S120422. The terminal device performs neighboring area measurement on the second network device within the first time window.

The offset between the start time of the first time window and the reference time is the difference between the first delay and the second delay. Exemplarily, as shown in FIG16, the first delay is the propagation delay between the reference position in the first area and the first network device; the second delay is the propagation delay between the reference position in the first area and the second network device.

Exemplarily, the position of the first network device can be determined based on the ephemeris information of the first network device, and then the propagation delay between the reference position in the first area and the first network device can be determined. Similarly, the position of the second network device can be determined based on the ephemeris information of the second network device, and then the propagation delay between the reference position in the first area and the second network device can be determined.

Exemplarily, the propagation delay between the reference position in the first area and the first network device is equal to the distance between the reference position in the first area and the first network device divided by the speed of light. The propagation delay between the reference position in the first area and the second network device is equal to the distance between the reference position in the first area and the second network device divided by the speed of light.

Exemplarily, the reference time and the offset may be universal time chiming (UTC), or the units of the reference time and the offset may be system frame number, subframe number, time slot number, orthogonal frequency division multiplexing (OFDM) symbol, etc. The reference time may be determined by the terminal device itself, or may be configured by the first network device, without limitation.

Exemplarily, the offset between the start time of the first time window and the reference time may also be referred to as a synchronization signal block (SSB) measurement timing configuration (SMTC) offset.

In a possible implementation, the above-mentioned method 1 and method 2 may be combined. For example, the terminal device may perform neighboring cell measurement on the second network device within the first time window before the remaining service time of the first cell ends.

In a possible implementation, the first elevation angle, the ephemeris information of the first network device, or the ephemeris information of the second network device may be indicated by the first network device to the terminal device. For example, the first information further indicates at least one of the following: elevation angle information, ephemeris information of the first network device, or ephemeris information of the second network device. Among them, the elevation angle information indicates the first elevation angle. Of course, the first network device may indicate at least one of the above items through other information other than the first information, without limitation.

In addition, the first information may also indicate an identifier of a reference area. The reference area is an area in the first cell, or an area in the coverage area or service area of the first cell. Exemplarily, the reference area may be an area where the cell center of the first cell is located.

In the case where the first information indicates the identifier of the reference area, the above step S1203 may not be performed, and in the above step S1204, the terminal device performs mobility management according to the identifier of the reference area. Exemplarily, the implementation of the terminal device performing mobility management according to the identifier of the reference area is similar to the implementation of the terminal device performing mobility management according to the identifier of the first area, and the first area in the above method 1 or method 2 can be replaced by the reference area, which will not be repeated here.

In a possible implementation, in the above-mentioned method 1, since the terminal device starts the neighboring cell measurement before the remaining service time of the first cell ends, and whether the first cell is covered is determined by the movement of the network device, therefore, method 1 can be applicable to the scenario where the cell reselection is triggered by the movement of the first network device.

In addition, in the above-mentioned method 2, the terminal device performs neighboring cell measurement within the first time window, and the starting time of the first time window is related to the propagation delay between the terminal device and the network device. Due to the movement of the network device, the network device may be located at different positions at different times, so that the propagation delay between the terminal device and the network device varies with time. Therefore, method 2 can also be applied to the scenario where cell reselection is triggered by the movement of the first network device.

Mode 3: The terminal device performs mobility management according to the identifier of the first area, including: when at least one of the following is met, the terminal device performs neighboring area measurement, or starts neighboring area measurement:

1) The identifier of at least one second area does not include the identifier of the first area.

The second area is the area served by the beam of the first network device, or the second area is the activated area. Condition 1) can also be understood as: at least one second area does not include the first area, or the area served by the beam of the first network device does not include the first area, or the first area is not served by the beam of the first network device.

2) The distance between the reference position in the first area and the reference position in the third area is greater than or equal to a first threshold.

The reference position in the first area is determined according to the identification of the first area, and reference may be made to the above related description. The third area is an edge area in at least one second area.

As a possible implementation, the edge area may be an area in the at least one second area where the distance between the reference position and the terminal device is the largest. Exemplarily, the third area may also be referred to as an edge area in the at least one second area.

For example, taking the case where the beam of the first network device serves three second areas, which are respectively recorded as second area 1, second area 2 and third area 3, if the distance between the terminal device and the reference positions in the three second areas are 10km, 20km and 15km respectively, then the third area is the second area 2.

As another possible implementation, the edge area may be an area in the at least one second area where the distance between the reference position and the central position of the coverage area of the first network device is the largest.

3) The distance between the reference position in the first area and the reference position in the reference area is greater than or equal to a first threshold.

Among them, the reference position in the first area is determined according to the identification of the first area, and the above-mentioned relevant instructions can be referred to. The reference area is an area in the first cell, or an area in the coverage area or service area of the first cell. The first cell is a cell managed by the first network device, and the first cell can be the current service cell of the terminal device. Exemplarily, the reference area can be the area where the cell center of the first cell is located. The position of the reference area can be determined according to the identification of the reference area.

4) The difference between the identifier of the first area and the identifier of the reference area is greater than or equal to a first threshold.

5) The distance between the reference position in the reference area and the position of the terminal device is greater than or equal to a first threshold.

6) The distance between the location of the terminal device and the reference location in the third area is greater than or equal to the first threshold.

It is understandable that in the above conditions 1) to 6), the values of the first threshold under different conditions may be the same or different. For example, the values of the first threshold in conditions 2) and 3) are the same, and the values of the first threshold in conditions 2) and 4) are different.

In a possible implementation, at least one second area, reference area or first threshold may be indicated by the first network device to the terminal device. For example, the first information further indicates at least one of the following: an area pattern, an identifier of the reference area or the first threshold. The area pattern indicates an identifier of at least one second area. Of course, the first network device may indicate at least one of the above items through other information other than the first information, without limitation.

As a possible implementation, the area pattern may include an identifier of each second area in the at least one second area. That is, the area pattern includes identifiers of each area served by the beam of the first network device.

Alternatively, the area pattern may be a bitmap, which includes M bits, where M is the total number of areas included in the coverage area or service area of the first network device, and M is a positive integer. The M bits correspond one-to-one to the M areas included in the coverage area or service area of the first network device. When the mth bit is set to a preset value, the area corresponding to the mth bit is the area served by the beam of the first network device, or the area corresponding to the mth bit is the second area or the activation area; when the mth bit is not set to a preset value, the area corresponding to the mth bit is not the area served by the beam of the first network device, or the area corresponding to the mth bit is not the second area or the activation area. m＝1,2,…,M.

Exemplarily, the preset value may be 1, and correspondingly, the non-preset value may be 0; or, the preset value may be 0, and correspondingly, the non-preset value may be 1.

In addition, when the area pattern is a bitmap, the first network device may indicate the area in the coverage area or service area of the first network device to the terminal device in advance. For example, the identifiers of each area in the coverage area or service area of the first network device are sent to the terminal device. Taking the example that the coverage area or service area of the first network device includes areas identified as 1 to 100, the first network device may send identifiers {1, 2, ..., 100} to the terminal device in advance.

As a possible implementation, regarding the indication of the first threshold, the first network device may send the value of the first threshold to the terminal device; or, the first network device may indicate a unit value to the terminal device, and the first threshold may be the product of the unit value and the area radius.

In a possible implementation, the conditions in the above-mentioned method three are related to the location of the terminal device, and when the terminal device is in different locations, the satisfaction of the above-mentioned conditions may be different. Therefore, the above-mentioned method three can be applicable to the scenario where the movement of the terminal device triggers cell reselection. For example, as shown in Figure 17, the elliptical solid line represents the coverage area or service area of the first network device, and the regular hexagon in the elliptical solid line represents the area in the coverage area or service area. When the terminal device moves in the direction of the arrow, the location of the terminal device and the area where the terminal device is located change, resulting in changes in the satisfaction of the conditions described in the above-mentioned method three.

In a possible implementation, in the above-mentioned method three, the first network device can also indicate at least one of the following to the terminal device: the ephemeris information of the first network device, the ephemeris information of the second network device, or the measurement information related to the reselection, such as the frequency priority, the frequency point of the neighboring area, or the antenna polarization mode of the neighboring area.

Mode 4: As shown in FIG. 18 , the terminal device performs mobility management according to the identifier of the first area, including:

S120431. The terminal device determines whether an identifier of at least one fourth area includes an identifier of the first area.

Among them, the fourth area is an area among N _spot areas that can be covered by the first network device, or in other words, the fourth area is an area within the coverage area of the first network device; or, the fourth area is an area among N _spot areas that can be served by the beam of the first network device, or in other words, the fourth area is an area within the service area of the first network device.

It can be understood that the at least one fourth area refers to part or all of the coverage area or service area of the first network device. Exemplarily, taking the coverage area of the first network device including areas 1 to 100 as an example, the at least one fourth area can be areas 20 to 30, or areas 25-40, etc., without limitation.

In a possible implementation manner, step S120431 may also be understood as: the terminal device determines whether at least one fourth area includes the first area.

In a possible implementation, before step S120431, the first network device indicates an identifier of at least one fourth area to the terminal device. Further, the first network device also indicates access information corresponding to at least one fourth area to the terminal device. The access information corresponding to the fourth area is used for the terminal device in the fourth area to access the second network device.

Exemplarily, the first network device may indicate the identifier of at least one fourth area and the access information corresponding thereto to the terminal device through the first information. That is, the first information also indicates the identifier of at least one fourth area and the access information corresponding thereto.

Exemplarily, the access information includes at least one of the following: an identifier of the second network device, an identifier of the target beam, a random access resource, or a random access preamble. The target beam is a beam of the second network device. The random access resource may include a random access occasion (RACH occasion, RO), and the RO indicates the time domain and/or frequency domain resources occupied by the random access channel (random access channel, RACH). The random access preamble may be a dedicated preamble in a cell switching process.

Optionally, the access information corresponding to different fourth areas may be different, for example, the random access resources and/or second network devices corresponding to different fourth areas may be different. Exemplarily, as shown in FIG19, taking at least one fourth area including fourth area 1 and fourth area 2 as an example, assuming that the access information corresponding to fourth area 1 includes the identifier of second network device 1 and random access resource 1, and the access information corresponding to fourth area 2 includes the identifier of second network device 2 and random access resource 2, wherein second network device 1 and second network device 2 are different network devices, and the time domain position and/or frequency domain position of random access resource 1 and random access resource 2 are different. Then, the terminal device in fourth area 1 can use random access resource 1 to access second network device 1, and the terminal device in fourth area 2 can use random access resource 2 to access second network device 2.

As a possible implementation, the identifier of the fourth area and the access information corresponding to the fourth area can be carried in a media access control (MAC) protocol data unit (PDU). For example, as shown in FIG20, a possible frame structure of a MAC PDU is shown.

Referring to Figure 20, the MAC PDU includes at least one MAC subPDU (MAC subPDU). The MAC subPDU is divided into a MAC subPDU including a MAC control element (CE), a MAC subPDU including a MAC service data unit (SDU), and a MAC subPDU including padding (optional). Among them, the MAC subPDU including a MAC CE includes a subheader and a MAC CE. The MAC subPDU including a MAC PDU includes a subheader and a MAC SDU.

Exemplarily, the identifier of the fourth area and the access information corresponding to the fourth area may be located in a subheader of the MAC PDU, such as in a subheader of a MAC subPDU containing the MAC PDU;

Alternatively, the identifier of the fourth area and the access information corresponding to the fourth area are located in the MAC CE of the MAC PDU;

Alternatively, the identifier of the fourth area is located in a subheader of the MAC PDU, such as in a subheader of a MAC subPDU containing the MAC PDU; the access information corresponding to the fourth area is located in the MAC CE of the MAC PDU.

Optionally, the identifiers of different fourth regions and their corresponding access information may be located in different MAC PDUs, or may be located in the same MAC PDU, without limitation. For example, the identifier of the fourth region 1 and its corresponding access information are located in MAC subPDU1, and the identifier of the fourth region 2 and its corresponding access information are located in MAC subPDU2; or, the fourth region 1 and its corresponding access information and the fourth region 2 and its corresponding access information are both located in MAC subPDU1.

In a possible implementation, in addition to the identifier of the fourth area and the access information corresponding to the fourth area, the first network device also indicates the identifier of the terminal device or the identifier of the terminal device group. After the terminal device in the fourth area receives the indication from the first network device, if the identifier of the terminal device indicated by the first network device includes its own identifier, or includes the identifier of the terminal device group to which it belongs, the terminal device accesses other network devices according to the access information corresponding to the fourth area.

Alternatively, the first network device may indicate different access information to different terminal devices or terminal device groups in the same fourth area, such as indicating different random access resources, different target network devices, etc.

In a possible implementation, since the terminal devices in the fourth area will access other network devices, the identifier of the fourth area, the identifier of the terminal device, or the identifier of the terminal device group indicated by the first network device to the terminal device can be understood as a switching command, which is used to instruct the terminal devices in the fourth area to access other network devices.

S120432: If the identifier of at least one fourth area includes the identifier of the first area, the terminal device accesses the second network device according to the access information corresponding to the first area.

Exemplarily, if the identifier of at least one fourth area includes the identifier of the first area, it means that the first network device instructs the terminal device in the first area to access other network devices or perform cell switching, so that the terminal device can access the second network device according to the access information corresponding to the first area.

As a possible implementation, if the first network device also indicates the identifier of the terminal device or the identifier of the terminal device group, then when the identifier of at least one fourth area includes the identifier of the first area, the terminal device also needs to determine whether the identifier of the terminal device indicated by the first network device includes its own identifier, or determine whether the identifier of the terminal device group indicated by the first network device includes the identifier of the terminal device group to which it belongs. If so, access the second network device according to the access information corresponding to the first area.

Exemplarily, according to the access information corresponding to the first area, accessing the second network device may include: sending a random access preamble code to the second network device using a transmission beam corresponding to a target beam on a random access resource indicated by the access information.

Based on the fourth method, the first network device can indicate the identifier of the fourth area and its corresponding access information to the terminal device, so that the terminal device in the fourth area can access other network devices according to the access information. In addition, the first network device can indicate different random access resources for different fourth areas, so that terminal devices in different fourth areas can access other network devices on different random access resources, reducing resource collisions when the terminal device performs random access, thereby improving the access success rate.

In the above-mentioned methods 1 to 4, the total number of areas and/or the radius of the area can be understood as the total number of areas and/or the radius of the area in which the first network device is effective or used. At this time, the first area is the area where the terminal device is located in the coverage area or service area of the first network device. In addition, the total number of areas and/or the radius of the area can also be the total number of areas and/or the radius of the area in which the second network device is effective or used. At this time, the terminal device can use the following method 5 for mobility management.

Mode 5: As shown in FIG. 21 , the terminal device performs mobility management according to the identifier of the first area, including:

S120441. The terminal device receives second information from the second network device according to the identifier of the first area.

The first area is the area where the terminal device is located in the coverage area or service area of the second network device. The second information indicates access information corresponding to the first area, and the access information is used for the terminal device in the first area to access the second network device.

Exemplarily, the access information includes at least one of the following: an identifier of a target beam, a random access resource, or a random access preamble. The random access resource or the random access preamble may refer to the relevant description in the above step S120431, which will not be described here.

Exemplarily, the target beam may be a beam corresponding to a handover (HO)-SSB of the second network device. HO-SSB is used for mobility management. In addition to HO-SSB, the second network device may also send a traditional SSB, which may be used to access the second network device.

Generally, the period of the traditional SSB is fixed (such as the period of the traditional SSB is generally 5/10/20/40/80/160ms), and the period of the traditional SSB is relatively short. The second network device may frequently send the traditional SSB to the terminal device based on the fixed period. The period of HO-SSB is adjustable (such as the period of HO-SSB can range from a few seconds to hundreds of seconds), the period span of HO-SSB is relatively large, and the period of HO-SSB is relatively long compared to the period of the traditional SSB. The second network device can send HO-SSB every few seconds or hundreds of seconds.

In addition, the service area of the traditional SSB is different from the service area of the HO-SSB. The HO-SSB generally serves the area where the cell switching/cell reselection is about to be performed. As the second network device moves, the service area of the HO-SSB also changes.

As a possible implementation, the second network device may carry the second information through a physical downlink control channel (PDCCH). Further, the PDCCH may be scrambled using the identifier of the first region. Therefore, the terminal device receives the second information from the second network device according to the identifier of the first region, which may include: the terminal device parses the PDCCH according to the identifier of the first region, thereby obtaining the second information carried in the PDCCH.

Optionally, the second network device may send access information corresponding to different areas through different PDCCHs. Further, different PDCCHs may be encrypted using the identifiers of the corresponding areas. For example, if PDCCH#1 carries access information corresponding to area 1 and PDCCH#2 carries access information corresponding to area 2, PDCCH#1 is encrypted using the identifier of area 1 and PDCCH#2 is encrypted using the identifier of area 2. The access information corresponding to different areas may be different.

S120442. The terminal device accesses the second network device according to the access information corresponding to the first area.

Exemplarily, the terminal device accessing the second network device according to the access information corresponding to the first area may include: sending a random access preamble code to the second network device using a transmitting beam corresponding to a target beam on a random access resource indicated by the access information.

Exemplarily, it can be considered that the scheme corresponding to the above-mentioned method five is applicable to the following scenario: the terminal device first accesses the first network device and maintains the RRC connection state on the first network device. Subsequently, the first network device indicates to the terminal device the total number of areas and/or the radius of the area in which the second network device is effective or in the time domain, and the terminal device determines the area (i.e., the first area) where the terminal device is located in the coverage area or service area of the second network device based on its own location information. Then, according to the identifier of the first area, the second information from the second network device is received, and according to the access information of the first area indicated by the second information, the second network device is accessed. That is, it can be considered that the terminal device switches from the first network device to the second network device.

Based on the fifth method, the second network device can indicate the access information corresponding to each area, so that the terminal device in the area can access the second network device according to the access information. In addition, the second network device can indicate different random access resources for different areas, so that the terminal devices in different areas can access the second network device on different random access resources, reducing resource collisions when the terminal devices perform random access, thereby improving the access success rate.

In a possible implementation, the solution described in the fifth method above can be applied to the switching process shown in FIG22. As shown in FIG22, the switching process includes the following steps:

S2201. The terminal device sends a measurement report and/or location information of the terminal device to the first network device. Correspondingly, the first network device receives the measurement report and/or location information of the terminal device from the terminal device.

Exemplarily, the measurement report includes a signal measurement result of a conventional SSB (such as NR-SSB). The location information of the terminal device may be indicated by information of the first area, such as an identifier of the first area or a reference location indication in the first area.

Optionally, before step S2201, the first network device may send a measurement configuration to the terminal device, and the terminal device may perform measurements according to the measurement configuration and report the measurement results.

Optionally, after receiving the measurement report and/or the location information of the terminal device, the first network device can perform layer 1/layer 2 triggered mobility (LTM) candidate preparation.

S2202a. Network devices exchange HO-SSB and handover related configuration information.

Exemplarily, FIG22 takes the interaction between the first network device and the second network device as an example for explanation. The first network device can be understood as a source network device, and the second network device can be understood as a candidate network device. Of course, there can be multiple candidate network devices (not shown in FIG22), and there is a target network device among the multiple candidate network devices.

Exemplarily, the configuration information may include at least one of the following: HO-SSB measurement period, measurement duration, measurement offset, ephemeris information of the network device, or access resource configuration corresponding to different time periods, such as random access preamble index, mask index, RO resources, or radio network temporary identity (RNTI).

S2202b, the first network device sends the LTM candidate configuration and the conditional handover (CHO) trigger condition to the terminal device. Correspondingly, the terminal device receives the LTM candidate configuration and the CHO trigger condition from the first network device.

Exemplarily, the LTM candidate configuration may be an LTM RRC related configuration, which may include at least one of the information described in step S2202a. The CHO trigger condition is used to determine whether to perform a cell handover. When the CHO trigger condition is met, the terminal device performs a cell handover, and when the CHO trigger condition is not met, the cell handover is not performed.

Exemplarily, the first network device may send an RRC reconfiguration message to the terminal device, wherein the RRC reconfiguration message carries the LTM candidate configuration and/or the CHO trigger condition.

S2203, the terminal device sends an RRC reconfiguration complete message to the first network device. Correspondingly, the first network device receives the RRC reconfiguration complete message from the terminal device.

S2204a. The terminal device performs downlink synchronization with the second network device according to the HO-SSB of the second network device.

Exemplarily, the terminal device may receive the HO-SSB from the second network device, and perform downlink synchronization with the second network device according to the synchronization signal carried therein.

S2204b. The terminal device obtains timing information of the second network device.

Exemplarily, the timing information may be a timing advance (TA). The terminal device may determine the TA based on the ephemeris information of the second network device, the location information of the terminal device, etc. After acquiring the timing information of the second network device, it may be considered that the terminal device and the second network device have completed uplink synchronization.

S2205. The terminal device performs layer 1/layer 3 measurement based on HO-SSB of the second network device.

Exemplarily, the terminal device may measure the HO-SSB of the second network device according to the HO-SSB measurement period, measurement duration, measurement offset, etc. configured in the above step S220b.

Exemplarily, after obtaining the measurement result of HO-SSB, the terminal device can perform LTM-CHO trigger event evaluation and LTM decision (LTM decision), that is, whether the measurement result meets the CHO trigger condition. If the measurement result meets the CHO trigger condition, the terminal device determines to perform cell switching; if the measurement result does not meet the CHO trigger condition, the terminal device does not perform cell switching and still maintains the RRC connection state in the first network device.

S2206: The second network device sends the second information to the terminal device. Correspondingly, the terminal device receives the second information from the second network device.

The second information indicates access information corresponding to the first area, and the access information is used for the terminal device in the first area to access the second network device. Please refer to the relevant description in the above step S120441, which will not be repeated here.

As a possible implementation, when the measurement result meets the CHO triggering condition, the terminal device determines to perform a cell handover, thereby receiving the second information from the second network device.

S2207: The terminal device accesses the second network device according to the access information corresponding to the first area. Please refer to the relevant description in the above step S120442, which will not be repeated here.

S2208. The second network device sends LTM completion response information to the terminal device; correspondingly, the terminal device receives the LTM completion response information from the second network device.

Based on the above steps, the terminal device can implement cell switching and access the second network device. In addition, the terminal device accesses the second network device according to the access resources indicated by the second network device. Therefore, the second network device can indicate different random access resources for different areas, so that terminal devices in different areas can access the second network device on different random access resources, reducing resource collisions when the terminal device performs random access, thereby improving the access success rate.

It is understandable that in the above embodiments, the methods and/or steps implemented by the terminal device may also be implemented by components (such as processors, chips, chip systems, circuits, logic modules, or software) that can be used in the terminal device; the methods and/or steps implemented by the network device may also be implemented by components (such as processors, chips, chip systems, circuits, logic modules, or software) that can be used in the network device. Among them, the chip system may be composed of chips, or the chip system may include chips and other discrete devices.

It is understandable that, in order to realize the above functions, the communication device includes hardware structures and/or software modules corresponding to the execution of each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

The embodiment of the present application can divide the functional modules of the communication device according to the above method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation.

Communication Device Figure 23 shows a schematic diagram of the structure of a communication device 230. The communication device 230 includes a processing module 2301 and a transceiver module 2302. The communication device 230 can be used to implement the functions of the above-mentioned terminal device or network device.

In some embodiments, the communication device 230 may further include a storage module (not shown in FIG. 23 ) for storing program instructions and data.

In some embodiments, the transceiver module 2302 may also be referred to as a transceiver unit for implementing a sending and/or receiving function. The transceiver module 2302 may be composed of a transceiver circuit, a transceiver, a transceiver or a communication interface.

In some embodiments, the transceiver module 2302 may include a receiving module and a sending module, which are respectively used to execute the receiving and sending steps performed by the network device in the above-mentioned method embodiments, and/or used to support other processes of the technology described in this document; the processing module 2301 may be used to execute the processing steps (such as determination, etc.) performed by the network device in the above-mentioned method embodiments, and/or used to support other processes of the technology described in this document.

Exemplarily, when the communication device 230 is used to implement the functions of the above terminal device:

The transceiver module 2302 is used to receive the first information from the first network device, where the first information indicates information of an area, where the area is fixed relative to the earth, and the geographical location of the area is determined by an identifier of the area; the identifier of the first area is determined based on the location information of the terminal device and the first information, where the first area is the area where the terminal device is located; the processing module 2301 is used to perform mobility management based on the identifier of the first area.

In one possible design, the processing module 2301 is used to perform mobility management according to the identifier of the first area, including: the processing module 2301 is used to determine the reference position in the first area according to the identifier of the first area; the processing module 2301 is also used to determine the remaining service time of the first cell according to the reference position in the first area, the ephemeris information of the first network device and the first elevation angle; the processing module 2301 is also used to start the neighboring area measurement before the remaining service time ends. The first elevation angle is the minimum elevation angle corresponding to the first cell or the minimum elevation angle corresponding to the first area.

In one possible design, processing module 2301 is used to perform mobility management according to the identifier of the first area, including: processing module 2301 is used to determine the reference position in the reference area according to the identifier of the reference area and the total number of areas; processing module 2301 is also used to determine the remaining service time of the first cell according to the reference position in the reference area, the ephemeris information of the first network device and the first elevation angle; processing module 2301 is also used to start neighboring area measurement before the remaining service time ends. The first elevation angle is the minimum elevation angle corresponding to the first cell or the minimum elevation angle corresponding to the first area. The first cell is a cell managed by the first network device.

In a possible design, the processing module 2301 is used to perform mobility management according to the identifier of the first area, including: the processing module 2301 is used to determine the reference position in the first area according to the identifier of the first area; the processing module 2301 is also used to perform neighboring area measurement on the second network device within the first time window. The offset between the start time and the reference time of the first time window is the difference between the first delay and the second delay, the first delay is the propagation delay between the reference position in the first area and the first network device, and the second delay is the propagation delay between the reference position in the first area and the second network device.

In one possible design, a processing module 2301 is used to perform mobility management according to an identifier of a first area, including: a processing module 2301 is used to perform neighboring cell measurement when at least one of the following is met: the identifier of at least one second area does not include the identifier of the first area; or, the distance between a reference position in the first area and a reference position in the third area is greater than or equal to a first threshold, and the reference position in the first area is determined according to the identifier of the first area, and the third area is an edge area of at least one second area; or, the distance between the reference position in the first area and the reference position in the reference area is greater than or equal to the first threshold; or, the difference between the identifier of the first area and the identifier of the reference area is greater than or equal to the first threshold; the distance between the position of the terminal device and the reference position in the third area is greater than or equal to the first threshold; or, the distance between the position of the terminal device and the reference position in the reference area is greater than or equal to the first threshold.

In one possible design, a processing module 2301 is used to perform mobility management according to an identifier of a first area, including: a processing module 2301 is used to determine whether an identifier of at least one fourth area includes an identifier of the first area; and the processing module 2301 is also used to access a second network device according to access information corresponding to the first area when the identifier of at least one fourth area includes an identifier of the first area.

In one possible design, the processing module 2301 is used to perform mobility management according to the identifier of the first area, including: the processing module 2301 is used to receive second information from the second network device through the transceiver module 2302 according to the identifier of the first area, the second information indicating access information corresponding to the first area, and the access information is used for the terminal device in the first area to access the second network device; the processing module 2301 is also used to access the second network device according to the access information corresponding to the first area.

When the communication device 230 is used to implement the function of the first network device:

The processing module 2301 is used to obtain the first information, where the first information indicates information of a region, the region is fixed relative to the earth, and the geographical location of the region is determined by an identifier of the region; the transceiver module 2302 is used to send the first information to the terminal device.

Among them, all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here.

In the present application, the communication device 230 may be presented in the form of dividing various functional modules in an integrated manner. The "module" here may refer to a specific application-specific integrated circuit (ASIC), a circuit, a processor and a memory that executes one or more software or firmware programs, an integrated logic circuit, and/or other devices that can provide the above functions.

In some embodiments, when the communication device 230 in Figure 23 is a chip or a chip system, the function/implementation process of the transceiver module 2302 can be implemented through the input and output interface (or communication interface) of the chip or the chip system, and the function/implementation process of the processing module 2301 can be implemented through the processor (or processing circuit) of the chip or the chip system.

Since the communication device 230 provided in this embodiment can execute the above method, the technical effects that can be obtained can refer to the above method embodiments and will not be repeated here.

As a possible product form, the terminal device or network device described in the embodiment of the present application can also be implemented using the following: one or more field programmable gate arrays (FPGA), programmable logic devices (PLD), controllers, state machines, gate logic, discrete hardware components, any other suitable circuits, or devices capable of executing the present application. Any combination of circuits with various functions described in this article.

As another possible product form, the terminal device or network device described in the embodiment of the present application can be implemented by a general bus architecture. For ease of explanation, refer to Figure 24, which is a structural diagram of a communication device 2400 provided in an embodiment of the present application, and the communication device 2400 includes a processor 2401 and a transceiver 2402. The communication device 2400 can be a terminal device, or a chip or chip system therein; or, the communication device 2400 can be a network device, or a chip or chip system therein. Figure 24 only shows the main components of the communication device 2400. In addition to the processor 2401 and the transceiver 2402, the communication device may further include a memory 2403, and an input and output device (not shown in the figure).

Optionally, the processor 2401 is mainly used to process the communication protocol and communication data, and to control the entire communication device, execute the software program, and process the data of the software program. The memory 2403 is mainly used to store the software program and data. The transceiver 2402 may include a radio frequency circuit and an antenna. The radio frequency circuit is mainly used for converting baseband signals and radio frequency signals and processing radio frequency signals. The antenna is mainly used to transmit and receive radio frequency signals in the form of electromagnetic waves. Input and output devices, such as touch screens, display screens, keyboards, etc., are mainly used to receive data input by users and output data to users.

Optionally, the processor 2401, the transceiver 2402, and the memory 2403 may be connected via a communication bus.

When the communication device is turned on, the processor 2401 can read the software program in the memory 2403, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 2401 performs baseband processing on the data to be sent, and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then sends the radio frequency signal outward in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 2401. The processor 2401 converts the baseband signal into data and processes the data.

In another implementation, the RF circuit and antenna may be arranged independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna may be arranged remotely from the communication device.

In some embodiments, in terms of hardware implementation, those skilled in the art may conceive that the communication device 230 may take the form of a communication device 2400 as shown in FIG. 24 .

As an example, the function/implementation process of the processing module 2301 in FIG23 can be implemented by the processor 2401 in the communication device 2400 shown in FIG24 calling the computer execution instructions stored in the memory 2403. The function/implementation process of the transceiver module 2302 in FIG23 can be implemented by the transceiver 2402 in the communication device 2400 shown in FIG24.

As another possible product form, the terminal device or network device in the present application may adopt the composition structure shown in Figure 25, or include the components shown in Figure 25. Figure 25 is a schematic diagram of the composition of a communication device 2500 provided by the present application, and the communication device 2500 may be a network device or a module or chip or system on chip in a network device; or the communication device 2500 may be a terminal device or a module or chip or system on chip in a terminal device.

As shown in FIG. 25 , the communication device 2500 includes at least one processor 2501 and at least one communication interface (FIG. 25 is merely an example of a communication interface 2504 and a processor 2501). Optionally, the communication device 2500 may also include a communication bus 2502 and a memory 2503.

Processor 2501 may be a general-purpose central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. Processor 2501 may also be other devices with processing functions, such as circuits, devices, or software modules, without limitation.

The communication bus 2502 is used to connect different components in the communication device 2500 so that the different components can communicate. The communication bus 2502 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in FIG. 25, but it does not mean that there is only one bus or one type of bus.

The communication interface 2504 is used to communicate with other devices or communication networks. Exemplarily, the communication interface 2504 can be a module, a circuit, a transceiver, or any device capable of implementing communication. Optionally, the communication interface 2504 can also be an input and output interface located in the processor 2501 to implement signal input and signal output of the processor.

The memory 2503 may be a device with a storage function, used to store instructions and/or data, wherein the instructions may be computer programs.

Exemplarily, the memory 2503 may be a read-only memory (ROM) or other types of static storage devices that can store static information and/or instructions, or a random access memory (RAM) or other types of dynamic storage devices that can store information and/or instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device. Etc., no restrictions.

It should be noted that the memory 2503 may exist independently of the processor 2501, or may be integrated with the processor 2501. The memory 2503 may be located inside the communication device 2500, or may be located outside the communication device 2500, without limitation. The processor 2501 may be used to execute instructions stored in the memory 2503 to implement the method provided in the following embodiments of the present application.

As an optional implementation, the communication device 2500 may further include an output device 2505 and an input device 2506. The output device 2505 communicates with the processor 2501 and may display information in a variety of ways. For example, the output device 2505 may be a liquid crystal display (LCD), a light emitting diode (LED) display device, a cathode ray tube (CRT) display device, or a projector. The input device 2506 communicates with the processor 2501 and may receive user input in a variety of ways. For example, the input device 2506 may be a mouse, a keyboard, a touch screen device, or a sensor device.

In some embodiments, in terms of hardware implementation, those skilled in the art may conceive that the communication device 230 shown in FIG. 23 may take the form of the communication device 2500 shown in FIG. 25 .

As an example, the function/implementation process of the processing module 2301 in FIG23 can be implemented by the processor 2501 in the communication device 2500 shown in FIG25 calling the computer execution instructions stored in the memory 2503. The function/implementation process of the transceiver module 2302 in FIG23 can be implemented by the communication interface 2504 in the communication device 2500 shown in FIG25.

It should be noted that the structure shown in FIG. 25 does not constitute a specific limitation on the network device. For example, in other embodiments of the present application, the network device may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

In some embodiments, an embodiment of the present application further provides a communication device, which includes a processor for implementing a method in any of the above method embodiments.

As a possible implementation, the communication device further includes a memory. The memory is used to store necessary computer programs and data. The computer program may include instructions, and the processor may call the instructions in the computer program stored in the memory to instruct the communication device to execute the method in any of the above method embodiments. Of course, the memory may not be in the communication device.

As another possible implementation, the communication device also includes an interface circuit, which is a code/data read/write interface circuit, which is used to receive computer execution instructions (computer execution instructions are stored in a memory, may be read directly from the memory, or may pass through other devices) and transmit them to the processor.

As another possible implementation manner, the communication device further includes a communication interface, and the communication interface is used to communicate with a module outside the communication device.

It can be understood that the communication device can be a chip or a chip system. When the communication device is a chip system, it can be composed of chips, or it can include chips and other discrete devices. The embodiments of the present application do not specifically limit this.

The present application also provides a computer-readable storage medium on which a computer program or instruction is stored. When the computer program or instruction is executed by a computer, the functions of any of the above method embodiments are implemented.

The present application also provides a computer program product, which implements the functions of any of the above method embodiments when executed by a computer.

Those skilled in the art will appreciate that, for the sake of convenience and brevity of description, the specific working processes of the systems, devices and units described above may refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

It is understood that the systems, devices and methods described in the present application can also be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, i.e., they may be located in one place, or they may be distributed over multiple network units. The components shown as units may or may not be physical units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented by a software program, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer program product. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more available media integrated therein. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state drive (SSD)), etc. In the embodiment of the present application, the computer may include the device described above.

Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art may understand and implement other variations of the disclosed embodiments by viewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "one" or "an" does not exclude multiple situations. A single processor or other unit may implement several functions listed in a claim. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

Although the present application has been described in conjunction with specific features and embodiments thereof, it is obvious that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely exemplary illustrations of the present application as defined by the appended claims, and are deemed to have covered any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, those skilled in the art may make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims (39)

A communication method, characterized in that the method comprises: receiving first information from a first network device, the first information indicating information of a region, the region being fixed relative to the earth, and the geographical location of the region being determined by an identifier of the region; Determine an identifier of a first area according to the location information of the terminal device and the first information, where the first area is an area where the terminal device is located; Mobility management is performed according to the identifier of the first area. The method according to claim 1 is characterized in that the geographical location of the area is also determined based on at least one of the following: the radius of the area, the radius of the earth, and the total number of areas. The method according to claim 2, characterized in that the region includes a reference position, and the three-dimensional coordinates of the reference position and the identifier of the region satisfy the following relationship:


Among them, i represents the identifier of the area, RL(i) represents the three-dimensional coordinates of the reference position, _Re represents the radius of the earth, [x] represents the decimal part of x, and N _spot represents the total number of the areas. The method according to claim 3, characterized in that the projection RL(x _i ,y _i ) of the reference position on the unit square and the identifier of the region satisfy the following relationship:
RL( _xi ) = (1 - _cosθi ) / 2
The unit square refers to a square in a Cartesian plane whose vertices are located at (0,0), (1,0), (0,1) and (1,1), RL( _xi ) represents the projection measurement of the reference position on the x-axis of the unit square, and RL( _yi ) represents the projection measurement of the reference position on the y-axis of the unit square. The method according to claim 3 or 4, characterized in that the Cartesian coordinates RL (x _i , y _i ) of the reference position and the identifier of the region satisfy the following relationship:
RL( _xi )＝i/ _Nspot
Wherein, RL( _xi ) represents the projection measurement of the reference position in the x-axis direction of the Cartesian coordinate system, and RL( _yi ) represents the projection measurement of the reference position in the y-axis direction of the Cartesian coordinate system. The method according to claim 2, characterized in that the region includes a reference position, and the three-dimensional coordinates of the reference position and the identifier of the region satisfy the following relationship:


Among them, i represents the identifier of the area, RL(i) represents the three-dimensional coordinates of the reference position, _Re represents the radius of the earth, and N _spot represents the total number of the areas. The method according to claim 2 is characterized in that the area includes a reference position, and the latitude and longitude coordinates of the reference position and the identifier of the area satisfy the following relationship:
RL(i)＝(lon(i),lat(i))

Wherein, lon(i) represents the longitude of the reference position, lat(i) represents the latitude of the reference position, and N _spot represents the total number of the areas. The method according to any one of claims 2 to 7, characterized in that the radius of the area and the total number of areas satisfy the following relationship:
Wherein, _Re represents the radius of the earth, N _spot represents the total number of the areas, and R _spot represents the radius of the area. The method according to any one of claims 1-8, characterized in that the first information indicates a total number of areas N _spot and/or a radius R _spot of the area. The method according to claim 9, characterized in that the first information further indicates at least one of the following: an identification of a reference area, elevation information, ephemeris information of the first network device, or ephemeris information of the second network device; The reference area is an area in a first cell, and the first cell is a cell managed by the first network device; the elevation angle information indicates the minimum elevation angle corresponding to the first cell, or indicates the minimum elevation angle corresponding to the area in the first cell. The method according to claim 10, characterized in that the mobility management is performed according to the identifier of the first area, comprising: determining a reference position in the first area according to the identifier of the first area; Determine the remaining service time of the first cell according to the reference position in the first area, the ephemeris information of the first network device, and a first elevation angle, where the first elevation angle is a minimum elevation angle corresponding to the first cell or a minimum elevation angle corresponding to the first area; Before the remaining service time ends, neighbor cell measurement is started. The method according to claim 10 or 11, characterized in that the mobility management is performed according to the identifier of the first area, comprising: determining a reference position in the first area according to the identifier of the first area; A neighboring area measurement is performed on a second network device within a first time window, and the offset between a start time and a reference time of the first time window is a difference between a first delay and a second delay, the first delay being a propagation delay between a reference position in the first area and the first network device, and the second delay being a propagation delay between a reference position in the first area and the second network device. The method according to claim 9, characterized in that the first information further indicates at least one of the following: a regional pattern, an identification of a reference region, or a first threshold; The area pattern indicates an identifier of at least one second area, the second area is the area served by the beam of the first network device; the reference area is one of the areas in the first cell, and the first cell is a cell managed by the first network device. The method according to claim 13, characterized in that the mobility management is performed according to the identifier of the first area, comprising: performing neighboring area measurement when at least one of the following is satisfied: The identifier of the at least one second area does not include the identifier of the first area; or, The distance between the reference position in the first area and the reference position in the third area is greater than or equal to the first threshold, the reference position in the first area is determined according to the identifier of the first area, and the third area is an edge area of the at least one second area; or The distance between the reference position in the first area and the reference position in the reference area is greater than or equal to the first threshold; or, The difference between the identifier of the first area and the identifier of the reference area is greater than or equal to the first threshold. The method according to claim 9 is characterized in that the first information also indicates the identifier of at least one fourth area and the access information corresponding to the at least one fourth area, the fourth area is an area among N _spot areas that can be covered by the first network device, and the access information is used for the terminal device in the fourth area to access the second network device. The method according to claim 15 is characterized in that the access information includes at least one of the following: an identifier of the second network device, an identifier of a target beam, a random access resource or a random access preamble code; and the target beam is a beam of the second network device. The method according to claim 15 or 16, characterized in that The identifier of the fourth area and the access information corresponding to the fourth area are located in a subheader of a media access control MAC protocol data unit PDU; or, The identifier of the fourth area and the access information corresponding to the fourth area are located in the MAC control element CE of the MAC PDU; or, The identifier of the fourth area is located in the subheader of the MAC PDU, and the access information corresponding to the fourth area is located in the MAC CE of the MAC PDU. The method according to any one of claims 15 to 17, characterized in that the mobility management is performed according to the identifier of the first area, comprising: determining whether the identifier of the at least one fourth area includes the identifier of the first area; If the identifier of the at least one fourth area includes the identifier of the first area, access is performed to the second network device according to access information corresponding to the first area. The method according to claim 9 is characterized in that the total number of the areas is the total number of areas where the second network device is effective, and/or the radius of the area is the radius of the area where the second network device is effective. The method according to claim 19, wherein performing mobility management according to the identifier of the first area comprises: receiving, according to the identifier of the first area, second information from the second network device, where the second information indicates access information corresponding to the first area, and the access information is used for a terminal device in the first area to access the second network device; Access the second network device according to the access information corresponding to the first area. A communication method, characterized in that the method comprises: Acquire first information, where the first information indicates information of a region, the region is fixed relative to the earth, and a geographical location of the region is determined by an identifier of the region; Send the first information to the terminal device. The method according to claim 21 is characterized in that the geographical location of the area is also determined based on at least one of the following: the radius of the area, the radius of the earth, and the total number of areas. The method according to claim 22, characterized in that the region includes a reference position, and the three-dimensional coordinates of the reference position and the identifier of the region satisfy the following relationship:


Among them, i represents the identifier of the area, RL(i) represents the three-dimensional coordinates of the reference position, _Re represents the radius of the earth, [x] represents the decimal part of x, and N _spot represents the total number of the areas. The method according to claim 23, characterized in that the projection RL(x _i ,y _i ) of the reference position on the unit square and the identifier of the region satisfy the following relationship:
RL( _xi ) = (1 - _cosθi ) / 2
The method according to claim 23 or 24, characterized in that the Cartesian coordinates RL(x _i ,y _i ) of the reference position in the Fibonacci grid and the identifier of the region satisfy the following relationship:
RL( _xi )＝i/ _Nspot
The method according to claim 25, characterized in that the region includes a reference position, and the three-dimensional coordinates of the reference position and the identifier of the region satisfy the following relationship:


Among them, i represents the identifier of the area, RL(i) represents the three-dimensional coordinates of the reference position, _Re represents the radius of the earth, and N _spot represents the total number of the areas. The method according to claim 22, characterized in that the area includes a reference position, and the latitude and longitude coordinates of the reference position and the identifier of the area satisfy the following relationship:
RL(i)＝(lon(i),lat(i))

Wherein, lon(i) represents the longitude of the reference position, lat(i) represents the latitude of the reference position, and N _spot represents the total number of the areas. The method according to any one of claims 22 to 27, characterized in that the radius of the area and the total number of areas satisfy the following relationship:
Wherein, _Re represents the radius of the earth, N _spot represents the total number of the areas, and R _spot represents the radius of the area. The method according to any one of claims 21-28, characterized in that the first information indicates a total number of areas N _spot and/or a radius R _spot of the area. The method according to claim 29, characterized in that the first information further indicates at least one of the following: an identification of a reference area, elevation information, ephemeris information of a first network device, or ephemeris information of a second network device; The reference area is an area in a first cell, and the first cell is a cell managed by the first network device; the elevation angle information indicates the minimum elevation angle corresponding to the first cell, or indicates the minimum elevation angle corresponding to the area in the first cell. The method according to claim 29, characterized in that the first information further indicates at least one of the following: a regional pattern, an identification of a reference region, or a first threshold; The area pattern indicates an identifier of at least one second area, the second area is the area served by the beam of the first network device; the reference area is one of the areas in the first cell, and the first cell is a cell managed by the first network device. The method according to claim 29 is characterized in that the first information also indicates the identifier of at least one fourth area and the access information corresponding to the at least one fourth area, the fourth area is an area among N _spot areas that can be covered by the first network device, and the access information is used for the terminal device in the fourth area to access the second network device. The method according to claim 32 is characterized in that the access information includes at least one of the following: an identifier of the second network device, an identifier of a target beam, a random access resource or a random access preamble code; and the target beam is a beam of the second network device. The method according to claim 32 or 33, characterized in that The identifier of the fourth area and the access information corresponding to the fourth area are located in a subheader of a media access control MAC protocol data unit PDU; or, The identifier of the fourth area and the access information corresponding to the fourth area are located in the MAC control element CE of the MAC PDU; or, The identifier of the fourth area is located in the subheader of the MAC PDU, and the access information corresponding to the fourth area is located in the MAC CE of the MAC PDU. The method according to claim 29 is characterized in that the total number of areas is the total number of areas where the second network device is effective, and/or the radius of the area is the radius of the area where the second network device is effective. A communication device, characterized in that the communication device includes a processor; the processor is used to run a computer program or instruction so that the communication device executes the method as described in any one of claims 1-20, or so that the communication device executes the method as described in any one of claims 21-35. A computer-readable storage medium, characterized in that the computer-readable storage medium stores computer instructions or programs, and when the computer instructions or programs are run on a computer, the method described in any one of claims 1 to 20 is executed, or the method described in any one of claims 21 to 35 is executed. A computer program product, characterized in that the computer program product includes computer instructions; when part or all of the computer instructions are run on a computer, the method described in any one of claims 1 to 20 is executed, or the method described in any one of claims 21 to 35 is executed. A chip, characterized by comprising: a memory for storing computer program instructions; A processor, configured to execute the computer program instructions so that a communication device including the chip performs the method according to any one of claims 1 to 35.