WO2025108312A1 - Communication method and communication apparatus - Google Patents

Abstract

The present application provides a communication method and a communication apparatus. The method comprises: a terminal device sends first information to a first network device, the first information comprising a positional relationship between the terminal device and a coverage range that corresponds to a second cell; the terminal device receives a trigger condition for a CHO of the first network device; and on the basis of the trigger condition for the CHO, the terminal device determines whether to hand over from the first network device to a second network device. The first network device is a network device corresponding to a first cell, the first network device is a source service network device of the terminal device, the second network device is a target service network device of the terminal device, and the second network device is a network device corresponding to the second cell. The first network device determines the trigger condition for the CHO on the basis of the positional relationship reported by the terminal device, and on the basis of the trigger condition for the CHO, the terminal device determines whether to hand over from the first network device to the second network device, so that the first network device does not need to reserve a handover resource for the terminal device in advance, and the resource overhead is reduced.

Description

Communication method and communication device

This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 22, 2023, with application number 202311579232.2 and invention name “Communication Method and Communication Device”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of communications, and more specifically, to a communication method and a communication device.

Background Art

Satellite communications and other non-terrestrial communication networks (NTN) have significant advantages such as global coverage, long-distance transmission, flexible networking, easy deployment and no geographical restrictions. They have been widely used in many fields such as maritime communications, positioning and navigation, disaster relief, scientific experiments, video broadcasting and earth observation.

In the scenario of satellite communication, the coverage area of satellite cells is particularly large, and the satellite coverage area includes some cells covered by terrestrial networks (TN). These terrestrial cells can be used as neighboring cells of satellite cells. According to the existing standard protocol, terminal devices need to continuously measure such neighboring cells for cell reselection and switching. However, in the scenario of satellite communication, for terminal devices that are not close to the coverage of neighboring cells, terminal devices do not need to measure the neighboring cells. If the distance between the terminal device and the neighboring cell is far, the network device still configures the measurement resources of the neighboring cell for the terminal device, resulting in a large measurement resource configuration overhead.

Summary of the invention

The present application provides a communication method and a communication device, which are combined with conditional handover (CHO) to implement the switching of terminal equipment from a non-terrestrial network to a terrestrial network, thereby reducing resource overhead.

In a first aspect, a communication method is provided, which can be executed by a terminal device. The terminal device here can refer to the terminal device itself, or a processor, module, chip, or chip system in the terminal device that implements the method, and this application does not limit this. The method includes:

The terminal device sends first information to the first network device, the first information including the positional relationship between the terminal device and the coverage area corresponding to the second cell, the second cell being the cell corresponding to the second network device; the terminal device receives second information from the first network device, the second information including the triggering condition of conditional switching CHO, the triggering condition of CHO being determined based on the first information; the terminal device determines whether to switch from the first network device to the second network device based on the triggering condition of CHO, wherein the first network device is the network device corresponding to the first cell, the first cell is the cell corresponding to the non-terrestrial network NTN, the first network device is the source service network device of the terminal device, the second network device is the target service network device of the terminal device, and the second cell is the cell corresponding to the terrestrial network TN.

It should be understood that the positional relationship between the terminal device and the coverage area corresponding to the second cell can be understood as: the distance between the terminal device and the edge of the coverage area corresponding to the second cell, and/or the distance between the terminal device and a reference point within the coverage area corresponding to the second cell. The reference point within the coverage area corresponding to the second cell may be the center point within the coverage area corresponding to the second cell, or other reference points other than the center point, which is not limited in this application.

It should also be understood that the first cell may be a cell not covered by a terrestrial network (or referred to as a cell corresponding to an NTN), and the second cell may be a cell covered by a terrestrial network (or referred to as a cell corresponding to a TN).

According to the method provided in the present application, the terminal device sends information (e.g., first information) to the first network device (or source network device) that can be used by the first network device to determine the relative position relationship between the geographical location of the terminal device and the coverage of the second cell. The first network device determines the triggering condition for conditional switching CHO based on the position relationship reported by the terminal device, and sends the triggering condition for CHO to the terminal device, and the terminal device further determines whether to switch to the second network device (or target network device) based on the triggering condition for CHO. In this method, the first network device determines the triggering condition for CHO based on the position relationship reported by the terminal device, and the terminal device further determines whether to switch from the first network device to the second network device based on the triggering condition for CHO, thereby avoiding the need for the first network device to reserve switching resources for the terminal device in advance and reducing resource overhead.

In combination with the first aspect, in some possible implementation methods, the terminal device determines whether to switch from the first network device to the second network device according to the trigger condition of the CHO, including: the terminal device determines that the trigger condition of the CHO is met, and the terminal device determines to switch from the first network device to the second network device, wherein the trigger condition of the CHO is: the terminal device determines that the signal quality of the second reference signal is higher than a first threshold, and the terminal device is located within the coverage range corresponding to the second cell, and the second reference signal is the reference signal of the second cell.

It should be understood that the first threshold may be a preset value, and the specific value is not limited in this application.

Based on the above technical solution, when the terminal device determines that the triggering condition of the CHO is met, the terminal device switches from the first network device to the second network device. That is, when the triggering condition of the CHO is met, the terminal device performs a switching operation. This avoids the terminal device from performing some unnecessary switching, reduces the switching frequency, and avoids the terminal device from generating some unnecessary power consumption.

In combination with the first aspect, in some possible implementation methods, the terminal device determines whether to switch from the first network device to the second network device according to the trigger condition of the CHO, including: the terminal device determines that the trigger condition of the CHO is met, and the terminal device determines to switch from the first network device to the second network device, wherein the trigger condition of the CHO is: the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the first distance is less than or equal to the second threshold, or, the trigger condition of the CHO is: the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage range corresponding to the second cell, and the second distance is greater than or equal to a third threshold, wherein the first distance is the relative distance between the terminal device and the second reference point, the second reference point is the reference point of the coverage area corresponding to the second cell, and the second distance is the distance between the position of the terminal device and the edge of the coverage area corresponding to the second cell.

It should be understood that the second reference signal in the present application is a reference signal of the coverage area corresponding to the second cell. The signal quality in the present application is an indicator for measuring signal quality, for example, it may refer to one or more of the parameters such as signal strength, signal-to-noise ratio, signal-to-interference-to-noise ratio, etc. of the reference signal.

It should also be understood that the first threshold, the second threshold, and the third threshold may be preset or configured by the network device, and the specific values are not limited in this application.

It should also be understood that the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the second distance is greater than or equal to the third threshold. The terminal device is located within the coverage area corresponding to the second cell, that is, the distance between the terminal device and the edge of the coverage area corresponding to the second cell is less than the radius of the coverage area of the second cell.

Based on the above technical solution, when the terminal device determines that the triggering condition of the CHO is met, the terminal device switches from the first network device to the second network device. That is, when the triggering condition of the CHO is met, the terminal device performs a switching operation. This avoids the terminal device from performing some unnecessary switching, reduces the switching frequency, and saves resource overhead.

In a possible implementation, the triggering condition of the CHO may be independent of the signal quality of the second reference signal, and the triggering condition of the CHO is related to the positional relationship between the terminal device and the coverage area corresponding to the second cell.

For example, the triggering condition of the CHO is: the first distance is less than or equal to the second threshold. The first distance represents the distance between the terminal device and the second reference point.

It should be understood that when the distance between the terminal device and the second reference point is less than or equal to the second threshold, that is, the terminal device can determine that the trigger condition of CHO is met, the terminal device switches from the first network device to the second network device.

For another example, the trigger condition of the CHO is: the terminal device is located within the coverage area corresponding to the second cell, and the second distance is greater than or equal to the third threshold. The second distance represents the distance between the terminal device and the edge position of the coverage area corresponding to the second cell.

It should be understood that when the terminal device is located within the coverage area corresponding to the second cell, and the second distance is greater than or equal to the third threshold, in other words, the terminal device is located at a relatively central position within the coverage area corresponding to the second cell. The terminal device can determine that the triggering condition of CHO is met, and the terminal device switches from the first network device to the second network device.

It should also be understood that, according to the above examples, it can be seen that the CHO trigger condition provided in the present application may be related to the distance between the terminal device and the coverage area corresponding to the second cell, and has nothing to do with the quality of the second reference signal.

In combination with the first aspect, in some possible implementations, before the terminal device determines whether to switch from the first network device to the second network device according to the trigger condition of the CHO, the terminal device is located within the coverage range corresponding to the second cell, and the method also includes: the terminal device sends a first request message to the first network device, the first request message is used to request measurement and/or reporting configuration information corresponding to radio resource management (radio resource management, RRM), and the measurement and/or reporting configuration information corresponding to the RRM is used by the terminal device to measure the second cell; the terminal device receives the measurement configuration information corresponding to the RRM of the first network device.

It should be understood that the measurement and/or reported configuration information corresponding to the RRM is used by the terminal device to perform co-frequency measurement on the second cell, or This application does not limit the heterodyne frequency measurement.

Based on the above technical solution, the terminal device determines to switch from the first network device to the second network device according to the triggering condition of CHO. Before the terminal device switches, the terminal device requests the configuration information corresponding to RRM from the first network device, and the configuration information is used for measurement and/or reporting of the terminal device. Only when the terminal device meets the conditions will the terminal device request the corresponding configuration information of RRM from the first network device, and the first network device further requests the second network device to reserve resources for the terminal device according to the request of the terminal device, thereby reducing the waste of RRM resources.

In combination with the first aspect, in some possible implementation methods, when the terminal device determines that the signal quality of the second reference signal is higher than a first threshold based on the measurement and/or reporting configuration information corresponding to the RRM, the method also includes: the terminal device sends a second request information to the first network device, and the second request information is used to request the configuration resource information of the second cell from the first network device, wherein the second reference signal is a reference signal of the second cell.

Based on the above technical solution, after the terminal device receives the configuration information corresponding to the RRM, the terminal device further determines whether the signal quality of the second reference signal is higher than the first threshold. When the signal quality of the second reference signal is higher than the first threshold, the terminal device reports to the first network device to request the configuration resource information of the second cell, thereby reducing the waste of resources.

In combination with the first aspect, in some possible implementation methods, the terminal device determines whether to switch from the first network device to the second network device according to the trigger condition of the CHO, including: when the signal quality of the second reference signal is higher than a fourth threshold, the terminal device determines whether to switch from the first network device to the second network device according to the trigger condition of the CHO.

For example, the terminal device determines that the signal quality of the second reference signal is higher than a fourth threshold, the fourth threshold is greater than or equal to the first threshold, and the terminal device determines whether to switch from the first network device to the second network device according to the trigger condition of CHO.

Based on the above technical solution, when the signal quality of the second reference signal is higher than the first threshold, the terminal device sends a second request information for requesting the configuration resource information of the second cell to the first network device. When the signal quality of the second reference signal is higher than the first threshold and higher than the fourth threshold, the terminal device performs a switch from the first network device to the second network device. Whether the terminal device needs to perform a switch is further determined by the first threshold and the fourth threshold, thereby reducing the frequency of terminal device switching and reducing unnecessary switching.

In combination with the first aspect, in some possible implementation methods, the terminal device determines whether to switch from the first network device to the second network device based on the trigger condition of the CHO, including: the terminal device determines that the trigger condition of the CHO is not met, and the terminal device does not switch from the first network device to the second network device.

The terminal device is located within the coverage area corresponding to the second cell, and the distance between the terminal device and the second reference point is greater than or equal to a fifth threshold; or, the terminal device is located within the coverage area corresponding to the second cell, the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold, and the speed of the terminal device is greater than or equal to a first value; or, the signal quality of the second reference signal is greater than or equal to a first threshold, and the difference between the signal quality of the second reference signal and the signal quality of the first reference signal is greater than or equal to a second value and less than or equal to a third value, the signal quality of the second reference signal is greater than or equal to the first threshold, the second value is less than or equal to the third value, and the second value is a positive integer; or, the signal quality of the second reference signal is greater than or equal to the first threshold, and the difference between the signal quality of the second reference signal and the signal quality of the first reference signal is less than the second value; or, the signal quality of the second reference signal is less than the first threshold, the first reference signal is a reference signal of the first cell, and the second reference signal is a reference signal of the second cell.

It should be understood that the above-mentioned thresholds, as well as the first value, the second value and the third value can be preset, pre-configured, system-configured, network device-configured, or radio resource control (RRC)-configured, etc., and the specific sizes are not limited in this application.

Based on the above technical solution, when the terminal device determines that the triggering condition of CHO is not met, the terminal device determines not to switch, thereby reducing the terminal device from performing some unnecessary switching, reducing the frequency of terminal device switching, and reducing unnecessary power consumption of the terminal device.

In combination with the first aspect, in some possible implementations, the first threshold is a signal quality of a first reference signal, and the first reference signal is a reference signal of a first cell.

It should be understood that the value of the first threshold can be determined based on the signal quality of the reference signal in the first cell. That is, whether the quality of the second reference signal corresponding to the second cell meets the triggering condition of CHO can be determined based on whether the signal quality of the second reference signal is higher than the signal quality of the first reference signal.

In combination with the first aspect, in some possible implementations, the method further includes: the terminal device sending a third request information to the first network device, the third request information being used to request the first network device for configuration resource information of the second cell; the terminal device receiving radio resource measurement RRC configuration information from the first network device, the RRC configuration information including the configuration resource information of the second cell; The trigger condition for switching CHO of the terminal device; the terminal device sends RRC configuration completion information to the first network device.

It should be understood that the third request information can be carried in the same message as the above-mentioned first information and sent to the first network device, or carried in different messages and sent to the first network device, and this application does not limit this.

In combination with the first aspect, in some possible implementations, the third request information includes identification information of a coverage area corresponding to the second cell.

In a second aspect, a communication method is provided, which can be performed by a first network device. The first network device here can refer to the first network device itself, or a processor, module, chip, or chip system in the first network device that implements the method, and this application does not limit this. The method includes:

A first network device receives first information from a terminal device, the first information including a positional relationship between the terminal device and a coverage area corresponding to a second cell, the second cell being a cell corresponding to the second network device; the first network device sends second information to the terminal device, the second information including a triggering condition for conditional switching CHO, the triggering condition for CHO being determined based on the first information; wherein the first network device is a network device corresponding to a first cell, the first cell is a cell corresponding to a non-terrestrial network NTN, the first network device is a source service network device for the terminal device, the second network device is a target service network device for the terminal device, and the second cell is a cell corresponding to a terrestrial network TN.

According to the method provided by the present application, the first network device receives the relative position relationship between its own geographical location reported by the terminal device and the coverage range of the second cell. The first network device determines the trigger condition of the conditional switching CHO according to the position relationship reported by the terminal device, and sends the trigger condition of the CHO to the terminal device. In this method, the first network device determines the trigger condition of the CHO according to the position relationship reported by the terminal device, and the terminal device further determines whether to switch from the first network device to the second network device in combination with the trigger condition of the CHO, thereby avoiding the need for the first network device to reserve switching resources for the terminal device in advance, reducing resource overhead.

In conjunction with the second aspect, in some possible implementations, the triggering condition of the CHO includes one or more of the following:

The signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage area corresponding to the second cell, and the second reference signal is the reference signal of the second cell; the signal quality of the second reference signal is higher than the first threshold, and the first distance is less than or equal to the second threshold, and the first distance is the relative distance between the terminal device and the first reference point, and the first reference point is the reference point of the coverage area corresponding to the second cell; the signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage area corresponding to the second cell, the second distance is greater than or equal to the third threshold, and the second distance is the distance between the position of the terminal device and the edge of the coverage area corresponding to the second cell.

It should be understood that the second reference signal in the present application is a reference signal of the coverage area corresponding to the second cell. The signal quality in the present application is an indicator for measuring signal quality, for example, it may refer to one or more of the parameters such as signal strength, signal-to-noise ratio, signal-to-interference-to-noise ratio, etc. of the reference signal.

In a possible implementation, the triggering condition of the CHO may be independent of the signal quality of the second reference signal, and the triggering condition of the CHO is related to the positional relationship between the terminal device and the coverage area corresponding to the second cell.

For example, the triggering condition of the CHO is: the first distance is less than or equal to the second threshold. The first distance represents the distance between the terminal device and the second reference point.

It should be understood that when the distance between the terminal device and the second reference point is less than or equal to the second threshold, the terminal device can determine that the trigger condition of CHO is met.

For another example, the trigger condition of the CHO is: the terminal device is located within the coverage area corresponding to the second cell, and the second distance is greater than or equal to the third threshold. The second distance represents the distance between the terminal device and the edge position of the coverage area corresponding to the second cell.

It should be understood that when the terminal device is located within the coverage area corresponding to the second cell and the second distance is greater than or equal to the third threshold, in other words, the terminal device is located at a relatively central position within the coverage area corresponding to the second cell.

It should also be understood that, according to the above examples, it can be seen that the CHO trigger condition provided in the present application may be related to the distance between the terminal device and the coverage area corresponding to the second cell, and has nothing to do with the quality of the second reference signal.

It should also be understood that the first threshold, the second threshold, and the third threshold may be preset or configured by the network device, and the specific values are not limited in this application.

It should also be understood that the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the second distance is greater than or equal to the third threshold. The terminal device is located within the coverage area corresponding to the second cell, that is, the distance between the terminal device and the edge of the coverage area corresponding to the second cell is less than the radius of the coverage area of the second cell.

In conjunction with the second aspect, in some possible implementations, the terminal device is located within the coverage area corresponding to the second cell, and the method further includes: the first network device receives first request information from the terminal device, and the first request information is used to Request measurement and/or reporting configuration information corresponding to wireless resource management RRM, and the measurement and/or reporting configuration information corresponding to RRM is used by the terminal device to measure the second cell; the measurement and/or reporting configuration information corresponding to the RRM is sent by the first network device to the terminal device.

It should be understood that the measurement and/or reported configuration information corresponding to the RRM is used by the terminal device to perform co-frequency measurement or inter-frequency measurement on the second cell, and this application does not limit this.

In combination with the second aspect, in some possible implementation methods, when the signal quality of the second reference signal is higher than the first threshold, the method also includes: the first network device receives second request information from the terminal device, the second request information is used to request configuration resource information of the second cell, wherein the second reference signal is a reference signal of the second cell.

In combination with the second aspect, in some possible implementations, the method further includes: the first network device sends a switching request to the second network device, and the switching request is used to request the second network device to reserve switching resources for the terminal device.

In combination with the second aspect, in some possible implementations, the first threshold is a signal quality of the first reference signal, and the first reference signal is a reference signal of the first cell.

It should be understood that the value of the first threshold can be determined based on the signal quality of the reference signal in the first cell. That is, whether the quality of the second reference signal corresponding to the second cell meets the triggering condition of CHO can be determined based on whether the signal quality of the second reference signal is higher than the signal quality of the first reference signal.

In conjunction with the second aspect, in some possible implementations, the method further includes:

The first network device receives a third request message from the terminal device, wherein the third request message is used by the terminal device to request the configuration resource information of the second cell from the first network device; the first network device sends wireless resource measurement RRC configuration information to the terminal device based on the third request message, wherein the RRC configuration information includes a trigger condition for the conditional switching CHO; the first network device receives RRC configuration completion information from the terminal device.

In combination with the second aspect, in some possible implementations, the third request information includes identification information of a coverage area corresponding to the second cell.

According to a third aspect, a communication device is provided, which includes: a transceiver unit for sending first information to a first network device, the first information including a positional relationship between the terminal device and a coverage area corresponding to a second cell, the second cell being a cell corresponding to the second network device; the transceiver unit is also used to receive second information from the first network device, the second information including a trigger condition for conditional switching CHO, the trigger condition for CHO being determined based on the first information; a processing unit for determining whether to switch from the first network device to the second network device based on the trigger condition for CHO, wherein the first network device is a network device corresponding to the first cell, the first cell is a cell corresponding to a non-terrestrial network NTN, the first network device is a source service network device for the terminal device, the second network device is a target service network device for the terminal device, and the second cell is a cell corresponding to a terrestrial network TN.

The transceiver unit can perform the reception and transmission processing in the aforementioned first aspect, and the processing unit can perform other processing in the aforementioned first aspect except the transmission and reception in the first aspect.

In a fourth aspect, a communication device is provided, which includes: a transceiver unit for receiving first information from a terminal device, the first information including a positional relationship between the terminal device and a coverage area corresponding to a second cell, and the second cell is a cell corresponding to a second network device; a transceiver unit for sending second information to the terminal device, the second information including a trigger condition for conditional switching CHO, and the trigger condition for CHO is determined based on the first information; wherein the first network device is a network device corresponding to the first cell, the first cell is a cell corresponding to a non-terrestrial network NTN, the first network device is a source service network device of the terminal device, the second network device is a target service network device of the terminal device, and the second cell is a cell corresponding to a terrestrial network TN.

The transceiver unit can perform the reception and transmission processing in the aforementioned second aspect.

In a possible implementation, the communication device further includes a processing unit, which can perform other processing in the aforementioned second aspect except for the sending and receiving in the second aspect.

In a fifth aspect, the present application provides a communication device, the communication device comprising a processor, configured to implement the method described in any one of the implementations of the first aspect to the second aspect. The processor is coupled to a memory, the memory is configured to store instructions and data, and when the processor executes the instructions stored in the memory, the method described in any one of the implementations of the first aspect to the second aspect can be implemented.

Optionally, the communication device may further include a memory. Optionally, the memory may be coupled to the processor. Optionally, the communication device may further include a communication interface, which is used for the device to communicate with other devices. Exemplarily, the communication interface may be a transceiver, a hardware circuit, a bus, a module, a pin or other types of communication interfaces.

In one example, the communication device may be a network device, such as an access network device, or may be a device, module or chip disposed in the network device, or may be a device that can be used in conjunction with the network device.

In another example, the communication device may be a terminal device, or may be a device, a module, a chip, etc. provided in the terminal device, or a device that can be used in conjunction with the terminal device.

In a sixth aspect, the present application provides a communication system, comprising at least one of a terminal device and a first network device. The terminal device is used to execute the method provided in any one of the implementations in the first aspect, and the first network device is the method provided in any one of the implementations described in the second aspect.

In the seventh aspect, the present application also provides a computer program, which, when executed on a computer, enables the computer to execute the method described in any implementation of the first aspect or the second aspect.

In an eighth aspect, the present application further provides a computer program product, comprising instructions, which, when executed on a computer, enable the computer to execute the method described in any implementation of the first or second aspect.

In the ninth aspect, the present application also provides a computer-readable storage medium, in which a computer program or instruction is stored. When the computer program or instruction is executed on a computer, the computer executes the method described in any implementation of the first aspect or the second aspect.

In the tenth aspect, the present application also provides a chip, which is used to read a computer program stored in a memory and execute the method described in any implementation of the first aspect or the second aspect; or, the chip includes a chip for executing the method described in any implementation of the first aspect or the second aspect.

In the eleventh aspect, the present application further provides a chip system, which includes a processor for supporting a device to implement the method described in any implementation of the first aspect and the second aspect. In one possible design, the chip system also includes a memory, which is used to store the necessary programs and data of the device. The chip system can be composed of a chip, or it can include a chip and other discrete devices.

In a twelfth aspect, a communication device is provided, the device being used to execute the method provided in any one of the first to second aspects. Specifically, the device may include a unit and/or module, such as a processing unit and/or a communication unit, for executing the method provided in any one of the above implementations of any one of the first to second aspects.

In one implementation, the device is a communication device (such as a terminal device, or a first network device). When the device is a communication device, the communication unit may be a transceiver, or an input/output interface; the processing unit may be at least one processor. Optionally, the transceiver may be a transceiver circuit. Optionally, the input/output interface may be an input/output circuit.

In another implementation, the device is a chip, a chip system or a circuit used in a communication device. When the device is a chip, a chip system or a circuit used in a device, the communication unit may be an input/output interface, an interface circuit, an output circuit, an input circuit, a pin or a related circuit on the chip, the chip system or the circuit; the processing unit may be at least one processor, a processing circuit or a logic circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a communication system 100 applicable to an embodiment of the present application.

FIG. 2 is a schematic diagram of an application architecture applicable to an embodiment of the present application.

FIG. 3 is a schematic diagram of a satellite communication scenario.

FIG4 is a flow chart of a communication method provided in an embodiment of the present application.

FIG5 is a flowchart of another communication method provided in an embodiment of the present application.

FIG6 is a flowchart of another communication method provided in an embodiment of the present application.

FIG. 7 is a schematic diagram of the structure of a communication device 700 provided in an embodiment of the present application.

FIG8 is a schematic diagram of the structure of a communication device 800 provided in an embodiment of the present application.

DETAILED DESCRIPTION

The technical solution in this application will be described below in conjunction with the accompanying drawings.

The technical solution of the present application can be applied to satellite communication systems, high altitude platform station (HAPS) communications, drones and other non-terrestrial network (NTN) systems, for example, integrated communication and navigation (IcaN) systems, global navigation satellite systems (GNSS) and ultra-dense low-orbit satellite communication systems, etc.

Satellite communication systems can be integrated with traditional mobile communication systems. For example, the mobile communication system can be a fourth generation (4G) communication system (e.g., long term evolution (LTE) system), a worldwide interoperability for microwave access (WiMAX) communication system, a fifth generation (5G) communication system (e.g., new radio (NR) system), and future mobile communication systems.

The satellite communication system includes user equipment (UE) and network equipment. The user equipment may also be referred to as a user terminal, a mobile station, etc. The network equipment may include one or more satellites and ground station equipment, and the ground station equipment may also be referred to as a core network equipment. The satellite may be a low earth orbit (LEO) satellite, a non-geostationary earth orbit (NGEO) satellite, etc., and the satellite may provide communication services, navigation services, and positioning services to the terminal equipment through multiple beams. The satellite uses multiple beams to cover the service area, and different beams can communicate through one or more of time division, frequency division, and space division. The satellite communicates wirelessly with the terminal equipment by broadcasting communication signals and navigation signals, and the satellite can communicate wirelessly with the ground station equipment. The satellite mentioned in the embodiment of the present application may be a satellite base station, and may also include an orbital receiver or repeater for relaying information, or a network side device mounted on a satellite.

See Figure 1, which is a schematic diagram of a communication system 100 applicable to an embodiment of the present application. As shown in Figure 1, the satellite provides communication services to the terminal device through multiple beams. The satellite in this scenario is a non-geostationary earth orbit (NGEO) satellite, and the satellite is connected to the core network device. The satellite uses multiple beams to cover the service area, and different beams can communicate through one or more of time division, frequency division and space division. The satellite provides communication and navigation services to the terminal device by broadcasting communication signals and navigation signals. The satellite mentioned in the embodiment of the present application may also be a satellite base station, or a network-side device mounted on a satellite.

Satellite communication systems include transparent satellite architecture and non-transparent satellite architecture. Transparent transmission is also called bent-pipe forwarding transmission: the signal only undergoes frequency conversion, signal amplification and other processes on the satellite, and the satellite is transparent to the signal, as if it does not exist. Non-transparent transmission is also called regenerative (on-board access/processing) transmission: the satellite has some or all base station functions.

The terminal devices mentioned in the embodiments of the present application include various handheld devices with wireless communication functions, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to a wireless modem, and may specifically refer to user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication equipment, user agent or user device. The terminal device may also be a satellite phone, a cellular phone, a smart phone, a wireless data card, a wireless modem, a machine type communication device, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device or a wearable device, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, a terminal device in a 5G network or a future communication network, etc.

The ground station equipment is, for example, equipment in the core network (CN) of the existing mobile communication architecture (such as the 3GPP access architecture of the 5G network) or equipment in the core network of the future mobile communication architecture. The core network, as a bearer network, provides an interface to the data network, provides communication connection, authentication, management, policy control, and data service bearing for the user equipment (UE). Among them, CN may further include: Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Policy Control Function (PCF), User Plane Function (UPF) and other network elements. Among them, the AMF network element is used to manage the access and mobility of the UE, and is mainly responsible for the authentication of the UE, the mobility management of the UE, the paging of the UE and other functions.

The network device may also include, but is not limited to: evolved node B (eNB), baseband unit (BBU), access point (AP) in wireless fidelity (WIFI) system, wireless relay node, wireless backhaul node, transmission point (TP) or transmission reception point (TRP), etc. The network device may also be a gNB or TRP or TP in a 5G system, or one or a group of (including multiple antenna panels) antenna panels of a base station in a 5G system. In addition, the network device may also be a network node constituting a gNB or TP, such as a BBU, or a distributed unit (DU), etc. Alternatively, the network device may also be a device-to-device (D2D) communication system, a machine-to-machine (M2M) communication system, an Internet of Things (IoT), or a vehicle-connected vehicle. A device that performs network-side functions in a network communication system or other communication system.

FIG2 is a schematic diagram of an application architecture applicable to an embodiment of the present application. A ground mobile terminal UE accesses the network through a 5G new air interface. The 5G access network equipment is deployed on a satellite and connected to the ground core network through a wireless link. At the same time, there is a wireless link between satellites to complete the signaling interaction and user data transmission between access network equipment and access network equipment. The various network elements in FIG2 and their interfaces are described as follows:

Terminal device: A mobile device that supports the 5G new air interface, typically a mobile phone, pad, etc. It can access the satellite network through the air interface and initiate calls, surf the Internet, and other services.

5G access network equipment: mainly provides wireless access services, dispatches wireless resources to access terminals, provides reliable wireless transmission protocols and data encryption protocols, such as base stations.

5G core network: user access control, mobility management, session management, user security authentication, billing and other services. It consists of multiple functional units, which can be divided into functional entities of control plane and data plane. Access and mobility management unit (AMF) is responsible for user access management, security authentication, and mobility management. User plane unit (UPF) is responsible for managing the transmission of user plane data, traffic statistics and other functions.

Ground station: responsible for forwarding signaling and business data between satellite access network equipment and 5G core network.

5G New Air Interface: The wireless link between the terminal and access network equipment.

Xn interface: The interface between 5G access network equipment and access network equipment, mainly used for signaling interaction such as switching.

NG interface: The interface between 5G access network equipment and 5G core network, which mainly interacts with the core network's NAS and other signaling, as well as user business data.

Satellite communications have their own unique advantages over terrestrial communications. For example, satellite communications can provide a wider coverage area; satellite base stations are not easily damaged by natural disasters or external forces. If satellite communications are introduced into 5G communications in the future, communication services can be provided to areas such as oceans and forests that are not covered by terrestrial communication networks. Satellite communications can enhance the reliability of 5G communications, for example, ensuring that users on airplanes, trains, and other transportation receive better communication services. Satellite communications can provide 5G communications with more data transmission resources and increase the speed of the network. Therefore, supporting both terrestrial and satellite communications is an inevitable trend for future 5G communications, which has relatively large benefits in terms of wide coverage, reliability, multiple connections, and high throughput.

The biggest feature of satellite communication is the large round-trip transmission delay, and the terminal equipment needs to frequently switch beams and cells due to the movement of the satellite. Therefore, the integration of satellite and 5G communication requires the enhancement of the existing 5G protocol to adapt to satellite communication.

At present, the existing protocols discuss the issue of mobility management of satellite communications, and propose technical solutions for how terminal equipment can perform neighboring cell measurements in scenarios where the satellite communication coverage area is large and the satellite coverage area includes coverage of some ground cells.

As shown in Figure 3, the satellite coverage includes multiple ground cells, which can be used as adjacent cells (or neighboring cells) of the satellite cell. Based on the existing technical solutions, the terminal equipment needs to measure the neighboring cells all the time for cell reselection and switching. However, in the scenario of satellite communication, for terminal equipment that is not close to the coverage of the ground cell, this type of terminal equipment does not need to measure the neighboring cells that are not close. If the terminal equipment is relatively far away from the ground neighboring cell, the terminal equipment will only introduce additional power consumption when measuring this type of ground neighboring cell. Therefore, the above standard discusses that by indicating the coverage reference point of the ground cell and the radius corresponding to the reference point, the terminal equipment can determine whether the current terminal equipment is close to the ground neighboring cell. Among them, if the terminal equipment is not close to the ground neighboring cell, the terminal equipment does not need to measure the neighboring cell.

It can be seen that the method shown in Figure 3 divides the neighboring cell into relatively fuzzy ground coverage areas, and determines whether the terminal device is close to the ground neighboring cell through the reference point and radius of the ground coverage area. The terminal device further determines whether it is necessary to measure the neighboring cell. In particular, the network device will periodically and continuously configure resources for measuring neighboring cells to the terminal device so that the terminal device can measure the neighboring cell. Since the network device needs to configure measurement resources for the terminal device in advance, and the terminal device determines whether it is close to the neighboring cell based on the ground coverage area of the neighboring cell, and does not measure the neighboring cell, the terminal device does not need to use the measurement resources pre-configured by the network device to the terminal device to measure the neighboring cell, resulting in a large resource overhead.

Based on the technical problems existing in the above-mentioned existing technical solutions, the present application provides a communication method, which combines conditional handover (CHO) to realize the switching of terminal devices and reduce the overhead of network devices in configuring measurement resources for terminal devices.

The communication method provided in the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings, such as being applicable to the communication system shown in FIG. 1 above.

FIG4 is a flow chart of a communication method provided by an embodiment of the present application. As shown in FIG4 , the method may include the following steps:

401. A terminal device sends first information to a first network device.

Correspondingly, the first network device receives the first information from the terminal device.

The first information includes a positional relationship between the terminal device and a coverage area corresponding to the second cell. The second cell is a cell corresponding to the ground network TN. The first cell is a cell currently providing services for the terminal device, and the first cell is a cell corresponding to the non-ground network NTN.

It should be understood that the position relationship included in the first information is the position relationship between the terminal device and the coverage area corresponding to the second cell, wherein the position relationship can be the distance between the position of the terminal device and the position of a reference point within the coverage area corresponding to the second cell, or the position relationship can be the distance between the position of the terminal device and the edge of the coverage area corresponding to the second cell.

The reference point within the coverage area corresponding to the second cell may be a central point or a non-central point of the coverage area corresponding to the second cell.

It should be understood that the ground coverage range may be indicated to the terminal device by the first network device through a system message. The ground coverage range may include coverage areas of at least two ground network devices, or the ground coverage range may be the coverage area of one ground network device (eg, the second network device).

402. The terminal device receives second information from the first network device.

Correspondingly, the first network device sends second information to the terminal device.

The second information includes a triggering condition of the conditional handover CHO, and the triggering condition of the CHO is determined according to the first information.

In a possible implementation, the triggering conditions of the CHO include:

1.1) The terminal device determines that the signal quality of the second reference signal is higher than a first threshold, and the terminal device is located within the coverage area corresponding to the second cell. The second reference signal is a reference signal of the second cell.

The first threshold may be a preset value or a preconfigured value. For example, the first threshold may be a value related to the signal quality of the first reference signal, or the first threshold is the signal quality of the first reference signal. The first reference signal is the signal quality of the reference signal of the first cell.

It should be understood that the signal quality in the embodiments of the present application may be an indicator for measuring the signal quality of a reference signal, such as signal strength, signal-to-noise ratio, signal-to-interference-plus-noise ratio, and the like.

In another possible implementation, the triggering condition of the CHO includes one or more of the following:

1.2) The terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the first distance is less than or equal to the second threshold; or;

1.3) The terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage area corresponding to the second cell, and the second distance is greater than or equal to the third threshold.

Among them, the first distance is the relative distance between the terminal device and the second reference point, the second reference point is the reference point of the coverage area corresponding to the second cell, and the second distance is the distance between the position of the terminal device and the edge of the coverage area corresponding to the second cell.

The specific values of the first threshold, the second threshold, and the third threshold are not limited in this application. For example, the first threshold may be a signal quality corresponding to Event 3 or Event X (e.g., Event 5).

It should be understood that the trigger condition for satisfying CHO in 1.2) is: the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the distance between the terminal device and the second reference point is within a certain range. For example, the relative distance between the terminal device and the second reference point is less than or equal to the second threshold. The size of the second threshold is not limited in this application.

Assuming that the second reference point is the center point of the second cell, and the second threshold is greater than the radius of the coverage area corresponding to the second cell, that is, the terminal device is outside the coverage range of the second cell, and the signal quality of the second reference signal is higher than the first threshold, that is, the trigger condition of CHO is met; assuming that the second reference point is the center point of the second cell, and the second threshold is less than or equal to the radius of the coverage area corresponding to the second cell, that is, the terminal device is on the edge of the coverage range of the second cell or within the coverage range, and the signal quality of the second reference signal is higher than the first threshold, that is, the trigger condition of CHO is met.

It should be understood that the triggering condition for CHO in 1.3) is: the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage area corresponding to the second cell, the second distance is greater than or equal to the third threshold, and the second distance is the distance between the position of the terminal device and the edge of the coverage area corresponding to the second cell. Among them, the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, the terminal device is located within the coverage area of the second cell, and the distance between the terminal device and the edge of the coverage area corresponding to the second cell is within a certain range, that is, the triggering condition of CHO is met.

1.4) The first distance is less than or equal to the second threshold.

It should be understood that for 1.4) when the distance between the terminal device and the second reference point is less than or equal to the second threshold, that is, the terminal device determines The triggering conditions of CHO must be met.

1.5) The terminal device is located within the coverage area corresponding to the second cell, and the second distance is greater than or equal to the third threshold.

It should be understood that for 1.5), when the terminal device is located within the coverage area corresponding to the second cell, and the second distance is greater than or equal to the third threshold value. In other words, the terminal device is located at a relatively central position within the coverage area corresponding to the second cell, that is, the terminal device determines that the trigger condition of CHO is met.

It should also be understood that, with respect to 1.4 and 1.5) above, it can be seen that the CHO triggering condition may be related to the distance between the terminal device and the coverage area corresponding to the second cell, and has nothing to do with the quality of the second reference signal.

In another possible implementation, if the CHO triggering conditions in 1.1) to 1.5) above are not met, and/or if one or more of the following 2.1) to 2.5) are met, the terminal device is determined to not meet the CHO triggering conditions:

2.1) The terminal device is located within the coverage area corresponding to the second cell, and the distance between the terminal device and the second reference point is greater than or equal to a fifth threshold;

It should be understood that the trigger condition for not meeting CHO in 2.1) is: the terminal device is located within the coverage corresponding to the second cell, and the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold. When the terminal device is within the coverage corresponding to the second cell, but the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold, the trigger condition for CHO is still not met.

2.2) The terminal device is located within the coverage area corresponding to the second cell, the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold, and the speed of the terminal device is greater than or equal to the first value.

It should also be understood that the triggering condition for not meeting CHO for 2.2) is: the terminal device is located within the coverage area corresponding to the second cell, the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold, and the speed of the terminal device is greater than or equal to the first value. The terminal device is within the coverage area corresponding to the second cell, and the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold. Among them, the speed of the terminal device is greater than or equal to the first value, indicating that the terminal device is moving faster (the speed exceeds the first value), and the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold, that is, the triggering condition of CHO is not met.

2.3) The signal quality of the second reference signal is greater than or equal to the first threshold, and the difference between the signal quality of the second reference signal and the signal quality of the first reference signal is greater than or equal to the second value and less than or equal to the third value, the second value is less than or equal to the third value, and the second value is a positive integer.

It should also be understood that the trigger condition for not meeting CHO in 2.3) is: the signal quality of the second reference signal is greater than or equal to the first threshold, and the difference between the signal quality of the second reference signal and the signal quality of the first reference signal is greater than or equal to the second value, and less than or equal to the third value, the second value is less than or equal to the third value, and the second value is a positive integer. When the terminal device determines that the quality of the second reference signal is greater than or equal to the first threshold, and the portion of the signal quality of the second reference signal exceeding the signal quality of the first reference signal is greater than or equal to the second value, and less than or equal to the third value, the trigger condition of the CHO is not met.

2.4) The signal quality of the second reference signal is greater than or equal to the first threshold, and the difference between the signal quality of the second reference signal and the signal quality of the first reference signal is less than a second value;

2.5) The signal quality of the second reference signal is less than the first threshold.

Among them, the specific values of the first threshold, the fifth threshold, the first value, the second value, and the third value are not limited in this application.

403. The terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of CHO.

It should be understood that after the terminal device receives the trigger condition of CHO from the first network device, the terminal device determines whether the trigger condition of CHO is met or not based on information such as the signal quality of the second reference signal, the relationship between the location of the terminal device and the coverage range corresponding to the second cell, combined with relatively preset numerical values, thereby further determining whether it is possible to switch from the first network device to the second network device.

Assume that the terminal device determines that the CHO trigger condition is satisfied, that is, one or more of 1.1) to 1.3) in the above step 402 is satisfied, and the terminal device determines to switch from the first network device to the second network device.

It is also assumed that the terminal device determines that the CHO trigger condition is not met, that is, one or more of 2.1) to 2.5 in the above step 402 are met, or all of the conditions in 1.1) to 1.3) in the above step 402 are not met, and the terminal device determines not to switch from the first network device to the second network device.

According to the method shown in FIG4 , the terminal device reports to the first network device the relative position relationship between its own position and the coverage area corresponding to the second cell. The first network device determines and sends a CHO trigger condition to the terminal device based on the position relationship reported by the terminal device. The CHO trigger condition is determined based on the relative position relationship reported by the terminal device. The terminal device determines whether to switch based on the CHO trigger condition. If the terminal device determines that the CHO trigger condition is met, it determines to switch from the first network device to the second network device; if the terminal device determines that the CHO trigger condition is not met, it determines not to switch to the second network device. The terminal device determines whether to switch based on the CHO trigger condition. Whether switching is required is determined, thereby avoiding the first network device periodically configuring switching resources for the terminal device and reducing resource overhead.

It should be understood that when the first cell is a cell corresponding to NTN and the second cell is a cell corresponding to TN, the terminal device determines whether to switch from the cell corresponding to NTN to the cell corresponding to TN according to the triggering condition of CHO through the method shown in FIG4, thereby further realizing the conditional switching of the terminal device from NTN to TN.

FIG5 is a schematic flow chart of another communication method provided in an embodiment of the present application. As shown in FIG5 , the method may include the following steps:

501. The terminal device sends first information to the first network device.

Correspondingly, the first network device receives the first information from the terminal device.

The first information includes a positional relationship between the terminal device and a coverage area corresponding to the second cell. The second cell is a cell corresponding to the ground network TN. The first cell is a cell currently providing services for the terminal device, and the first cell is a cell corresponding to the non-ground network NTN.

It should be understood that step 501 is similar to step 401 in FIG. 4 . For details, please refer to the detailed introduction of step 401 .

502. The terminal device sends a request message #1 to the first network device.

Accordingly, the first network device receives the request message #1 from the terminal device.

The request message #1 is used by the terminal device to request the configuration resource information of the second cell from the first network device.

Optionally, the request message #1 includes identification information of the coverage area corresponding to the second cell, for example, the ID of the ground coverage area corresponding to the second cell.

It should be understood that the request message #1 and the first information in step 502 and step 501 can be carried in the same message and sent to the first network device; or, the request message #1 and the first information can be carried in different messages and sent to the first network device. That is, the request message #1 and the first information can be sent to the first network device at the same time, or sent to the first network device one after another, and the present application does not limit the order of execution of the steps.

For example, when the terminal device moves into the coverage area corresponding to the second cell, the terminal device sends a first message to the first network device, and the first message is used to indicate that the terminal device has moved into the coverage area of the second cell. At the same time, the terminal device requests the configuration resource information of the second cell from the first network device through request message #1. The configuration resource information of the second cell is used for the terminal device to switch from the first network device to the second network device.

503. The terminal device receives second information from the first network device.

Correspondingly, the first network device sends second information to the terminal device.

The second information includes a triggering condition of the conditional handover CHO, and the triggering condition of the CHO is determined according to the first information.

For the specific content of the triggering condition of CHO, please refer to the detailed introduction of step 402 in FIG. 4 , which will not be repeated here.

504. The first network device sends a switching request message to the second network device.

Correspondingly, the second network device receives the switching request information from the first network device.

It should be understood that the second network device is a network device of the second cell. After receiving the request information #1 from the terminal device, the first network device sends a switching request information to the second network device according to the request information #1. The switching request information is used to request the second network device to reserve switching resources for the terminal device.

It should also be understood that the switching request information #1 can be transmitted between the first network device and the second network device via the Xn interface, or the first network device can transmit the switching request message #1 to the second network device via the NG interface, and this application does not limit this.

It should also be understood that step 504 can be performed simultaneously with step 503, that is, the first network device simultaneously sends the second information to the terminal device and sends the request message #1 to the second network; or, step 504 and step 503 are performed successively, that is, step 504 can be performed before step 503 or after step 503.

505. The first network device receives switching response information from the second network device.

Correspondingly, the second network device sends switching response information to the first network device.

It should be understood that after receiving the switching request information from the first network device, the second network device reserves switching resources for the terminal device according to the switching request information, and sends the switching response information to the first network device.

It should also be understood that step 505 is the response information of step 504 .

506. The first network device sends RRC configuration information to the terminal device.

Correspondingly, the terminal device receives RRC configuration information from the first network device.

It should be understood that step 506 and step 504 may be performed simultaneously or sequentially, and this application does not limit the sequence.

507. The terminal device sends RRC configuration completion information to the first network device.

Correspondingly, the first network device receives RRC configuration completion information from the terminal device.

It should be understood that after the terminal device receives the RRC configuration information from the first network device, the terminal device performs adaptive configuration according to the RRC configuration. After completing the configuration, the terminal feeds back RRC configuration completion information to the first network device.

508. The terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of CHO.

For example, after the terminal device feeds back an RRC completion message to the first network device, the terminal device determines whether to switch from the first network device to the second network device according to the CHO trigger condition included in the second information in step 503 .

It should be understood that after the terminal device receives the trigger condition of CHO from the first network device, the terminal device determines whether the trigger condition of CHO is met or not based on information such as the signal quality of the second reference signal, the relationship between the location of the terminal device and the coverage range corresponding to the second cell, combined with relatively preset numerical values, thereby further determining whether it is possible to switch from the first network device to the second network device.

It should also be understood that the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of CHO. For a detailed description, please refer to the description of step 403 in Figure 4 above, which will not be repeated here.

According to the method shown in FIG. 5 above, the terminal device moves into the coverage area of the second cell and reports the location information to the first network device. The first network device can request information #1 to configure the configuration information corresponding to the second cell for the terminal device based on the reported location information, that is, the first network device does not need to configure the corresponding configuration information for each cell corresponding to the ground coverage area, thereby reducing the resources configured by the first network device and reducing resource overhead.

FIG6 is a schematic flow chart of another communication method provided in an embodiment of the present application. As shown in FIG6 , the method may include the following steps:

601. A terminal device sends first information to a first network device.

Correspondingly, the first network device receives the first information from the terminal device.

The first information includes a positional relationship between the terminal device and a coverage area corresponding to the second cell. The second cell is a cell corresponding to the ground network TN. The first cell is a cell currently providing services for the terminal device, and the first cell is a cell corresponding to the non-ground network NTN.

It should be understood that step 601 is similar to step 401 in FIG. 4 and step 501 in FIG. 5 . For details, please refer to the detailed introduction of step 401 above.

602. The terminal device receives second information from the first network device.

Correspondingly, the first network device sends second information to the terminal device.

The second information includes a triggering condition of the conditional handover CHO, and the triggering condition of the CHO is determined according to the first information.

For the specific content of the triggering condition of CHO, please refer to the detailed introduction of step 402 in FIG. 4 , which will not be repeated here.

603. The terminal device sends a request message #2 to the first network device.

Accordingly, the first network device receives the request message #2 from the terminal device.

The request message #2 is used by the terminal device to request the first network device for the measurement and/or reporting configuration information corresponding to the RRM. The measurement and/or reporting configuration information corresponding to the RRM is used by the terminal device to perform co-frequency measurement or inter-frequency measurement on the second cell.

It should be understood that the request message #2 and the first information in step 603 and step 601 can be carried in the same message and sent to the first network device; or, the request message #2 and the first information can be carried in different messages and sent to the first network device. That is, the request message #2 and the first information can be sent to the first network device at the same time, or sent to the first network device one after another, and the present application does not limit the order of execution of the steps.

For example, when the terminal device moves into the coverage area corresponding to the second cell, the terminal device sends a first message to the first network device, and the first message is used to indicate that the terminal device has moved into the coverage area of the second cell. At the same time, the terminal device requests the measurement and/or reporting configuration information corresponding to the RRM from the first network device through request message #2.

604. The first network device sends measurement and/or reporting configuration information corresponding to the RRM to the terminal device.

Correspondingly, the terminal device receives measurement and/or reported configuration information corresponding to the RRM from the first network device.

605. The terminal device sends a request message #3 to the first network device.

Correspondingly, the first network device receives the request message #3 from the terminal device.

The request message #1 is used by the terminal device to request the configuration resource information of the second cell from the first network device.

Optionally, the request message #1 includes identification information of the coverage area corresponding to the second cell, for example, the ID of the ground coverage area corresponding to the second cell.

It should be understood that step 605 is similar to step 502 in Figure 5 above, wherein request message #1 in Figure 5 and request message #3 in Figure 6 are both used to request configuration resource information of the second cell from the first network device. For details, please refer to the detailed introduction in Figure 5.

606. The first network device sends a switching request message to the second network device.

Correspondingly, the second network device receives the switching request information from the first network device.

It should be understood that the second network device is a network device of the second cell. For example, after the first network device receives the request information #3 from the terminal device, it sends a switching request information to the second network device according to the request information #3. The switching request information is used to request the second network device to reserve switching resources for the terminal device.

607: The first network device receives the switching response information from the second network device.

Correspondingly, the second network device sends switching response information to the first network device.

It should be understood that after receiving the switching request information from the first network device, the second network device reserves switching resources for the terminal device according to the switching request information, and sends the switching response information to the first network device.

608. The terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of CHO.

For example, the terminal device determines whether to switch from the first network device to the second network device according to the CHO trigger condition included in the second information in step 503 .

It should be understood that after the terminal device receives the trigger condition of CHO from the first network device, the terminal device determines whether the trigger condition of CHO is met or not based on information such as the signal quality of the second reference signal, the relationship between the location of the terminal device and the coverage range corresponding to the second cell, combined with relatively preset numerical values, thereby further determining whether it is possible to switch from the first network device to the second network device.

It should also be understood that the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of CHO. For a detailed description, please refer to the description of step 403 in Figure 4 above, which will not be repeated here.

It should also be understood that when the terminal device determines that the signal quality of the second reference signal is higher than the fourth threshold value, and the fourth threshold value is greater than or equal to the first threshold value in the trigger condition of CHO, the terminal device switches from the first network device to the second network device. When the signal quality of the second reference signal is higher than the first threshold value, the terminal device sends a request message #3 for requesting the configuration resource information of the second cell to the first network device. When the signal quality of the second reference signal is higher than the first threshold value and higher than the fourth threshold value, the terminal device performs a switch from the first network device to the second network device.

According to the method shown in FIG. 6 above, the terminal device determines to switch from the first network device to the second network device according to the triggering condition of CHO. Before the terminal device switches, the terminal device moves into the coverage area of the second cell, and the terminal device requests the configuration information corresponding to RRM from the first network device, and the configuration information is used for measurement and/or reporting by the terminal device. Only when the terminal device meets the conditions will the terminal device request the first network device for the corresponding configuration information of RRM, and the first network device further requests the second network device to reserve resources for the terminal device according to the request of the terminal device, thereby reducing the waste of RRM resources.

It should be understood that the above-mentioned Figures 5 and 6 are schematic diagrams of exemplary methods provided by the embodiments of the present application. Those skilled in the art may delete or adjust the steps included in the above-mentioned Figures 5 and 6, which are all variations of the embodiments of the present application, and the present application will not cite them one by one.

The method embodiment of the present application is described above in conjunction with the drawings, and the device embodiment of the present application is described below. It can be understood that the description of the method embodiment and the description of the device embodiment can correspond to each other, so the undescribed parts can refer to the previous method embodiment.

It can be understood that in the above-mentioned method embodiments, the methods and operations implemented by the terminal device can also be implemented by components that can be used for the terminal device (such as chips or circuits), and the methods and operations implemented by the network device can also be implemented by components that can be used for the network device (such as chips or circuits).

It can be understood that, unless otherwise specified or there is a logical conflict, the terms and/or descriptions between different embodiments are consistent and can be referenced to each other, and the technical features in different embodiments can be combined to form a new embodiment according to their internal logical relationships.

It is understood that in the present application, "first", "second" and various numerical numbers (e.g., #1, #2, etc.) indicate distinctions made for ease of description and are not used to limit the scope of the embodiments of the present application. For example, to distinguish between different messages, etc., rather than to describe a specific order or sequence. It should be understood that the objects described in this way can be interchanged where appropriate so as to be able to describe solutions other than the embodiments of the present application.

It is understood that in this application, "protocol" may refer to a standard protocol in the field of communications, such as 5G protocol, NR protocol, and related protocols used in future communication systems, and this application does not limit this. "Predefined" may include pre-definition. For example, protocol definition. "Preconfiguration" can be implemented by pre-saving corresponding codes, tables, or other methods that can be used to indicate relevant information in the device, and this application does not limit its specific implementation method.

It is understood that "storage" may refer to storage in one or more memories. One or more memories may be separately set or integrated in an encoder or decoder, a processor, or a communication device. One or more memories may also be partially separately set or partially integrated in a decoder, a processor, or a communication device. The type of memory may be any form of storage medium, which is not limited in this application.

The above mainly introduces the solution provided by the embodiment of the present application from the perspective of the interaction between various network elements. It can be understood that each network element, such as a transmitting end device or a receiving end device, includes a hardware structure and/or software module corresponding to the execution of each function in order to realize the above functions. Those skilled in the art should be aware that, in combination with the units and algorithm steps of each example described in the embodiments disclosed in this document, 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 exceed the scope of this application.

The embodiment of the present application can divide the functional modules of the transmitting end device or the receiving end device according to the above method example. For example, each functional module can be divided corresponding 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 functional division. There may be other division methods in actual implementation. The following is an example of dividing each functional module corresponding to each function.

FIG. 7 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application.

The device 700 includes a transceiver unit 710 and a processing unit 720, wherein the transceiver unit 710 can be used to implement corresponding communication functions, and the processing unit 720 can be used to perform data processing.

Optionally, the transceiver unit 710 may also be referred to as a communication interface or a communication unit, which includes a sending unit and/or a receiving unit. The transceiver unit 710 may be a transceiver (including a transmitter and/or a receiver), an input/output interface (including an input and/or output interface), a pin or a circuit, etc. The transceiver unit 710 may be used to perform the steps of sending and/or receiving in the above method embodiment.

Optionally, the processing unit 720 may be a processor (may include one or more), a processing circuit with a processor function, etc., and may be used to execute other steps except sending and receiving in the above method embodiment.

Optionally, the device 700 further includes a storage unit, which may be a memory, an internal storage unit (e.g., a register, a cache, etc.), an external storage unit (e.g., a read-only memory, a random access memory, etc.), etc. The storage unit is used to store instructions, and the processing unit 720 executes the instructions stored in the storage unit so that the communication device executes the above method.

In one design, the apparatus 700 may correspond to the network device (eg, the first network device or the second network device) in the above method embodiments, or a component of the network device (eg, a chip).

In another design, the apparatus 700 may correspond to the terminal device in the above method embodiment, or be a component (such as a chip) of the terminal device.

The device 700 can implement the steps or processes executed by the terminal device in the above method embodiment, wherein the transceiver unit 710 can be used to perform the transceiver related operations of the terminal device in the above method embodiment, and the processing unit 720 can be used to perform the internal operations of the terminal device in the above method embodiment except for sending and receiving information.

In one possible implementation, the transceiver unit 710 is used to send first information to the first network device, the first information including the positional relationship between the terminal device and the coverage area corresponding to the second cell, and the second cell is the cell corresponding to the second network device; the transceiver unit 710 is also used to receive second information from the first network device, the second information including the triggering condition of the conditional switching CHO, and the triggering condition of the CHO is determined according to the first information; the processing unit 720 is used to determine whether to switch from the first network device to the second network device according to the triggering condition of the CHO, wherein the first network device is the network device corresponding to the first cell, the first cell is the cell corresponding to the non-terrestrial network NTN, the first network device is the source service network device of the terminal device, the second network device is the target service network device of the terminal device, and the second cell is the cell corresponding to the terrestrial network TN.

The device 700 can implement the steps or processes executed by the first network device in the above method embodiment, wherein the transceiver unit 710 can be used to perform the transceiver-related operations of the first network device in the above method embodiment, and the processing unit 720 can be used to perform the internal operations of the first network device in the above method embodiment except for sending and receiving information.

In a possible implementation, the transceiver unit 710 is used to receive first information from a terminal device, the first information including a positional relationship between the terminal device and a coverage area corresponding to a second cell, the second cell being a cell corresponding to a second network device; the transceiver unit 710 is used to send second information to the terminal device, the second information including a triggering condition for conditional switching CHO, the triggering condition for CHO being determined based on the first information; wherein the first network device is a network device corresponding to the first cell, the first cell is a cell corresponding to a non-terrestrial network NTN, the first network device is a source service network device of the terminal device, and the second network device is a target service network device of the terminal device, The second cell is a cell corresponding to the ground network TN.

Among them, when the device 700 is used to execute the method in Figures 4 to 6, the transceiver unit 710 can be used to execute the steps of sending and receiving information in the method; the processing unit 720 can be used to execute the steps inside the device in the method except sending and receiving information.

It should be understood that the specific process of each unit executing the above corresponding steps has been described in detail in the above method embodiment, and for the sake of brevity, it will not be repeated here.

It should also be understood that the device 700 here is embodied in the form of a functional unit. The term "unit" here may refer to an application specific integrated circuit (ASIC), an electronic circuit, a processor (such as a shared processor, a dedicated processor or a group processor, etc.) and a memory for executing one or more software or firmware programs, a combined logic circuit and/or other suitable components that support the described functions. In an optional example, those skilled in the art can understand that the device 700 can be specifically a network device in the above-mentioned embodiments, and can be used to execute the various processes and/or steps corresponding to the network device in the above-mentioned method embodiments. To avoid repetition, it will not be repeated here.

The apparatus 700 of each of the above schemes has the function of implementing the corresponding steps performed by the devices (such as terminal devices and network devices) in the above methods. This function can be implemented by hardware, or by hardware executing corresponding software implementations. The hardware or software includes one or more modules corresponding to the above functions; for example, the transceiver unit can be replaced by a transceiver (for example, the sending unit in the transceiver unit can be replaced by a transmitter, and the receiving unit in the transceiver unit can be replaced by a receiver), and other units, such as the processing unit, can be replaced by a processor to respectively perform the transceiver operations and related processing operations in each method embodiment.

In addition, the transceiver unit 710 may also be a transceiver circuit (for example, may include a receiving circuit and a sending circuit), and the processing unit may be a processing circuit.

It should be noted that the device in FIG. 7 may be a network element or device in the aforementioned embodiment, or may be a chip or a chip system, such as a system on chip (SoC). The transceiver unit may be an input and output circuit or a communication interface; the processing unit may be a processor or a microprocessor or an integrated circuit integrated on the chip. This is not limited here.

FIG8 is a schematic diagram of the structure of a communication device 800 provided in an embodiment of the present application. The communication device 800 shown in FIG8 includes: a processor 810, a memory 820, and a transceiver 830. The processor 810 is coupled to the memory 820 and is used to execute instructions stored in the memory 820 to control the transceiver 830 to send signals and/or receive signals.

It should be understood that the processor 810 and the memory 820 can be combined into a processing device, and the processor 810 is used to execute the program code stored in the memory 820 to implement the above functions. In specific implementation, the memory 820 can also be integrated into the processor 810, or independent of the processor 810. It should be understood that the processor 810 can also correspond to each processing unit in the above communication device, and the transceiver 830 can correspond to each receiving unit and sending unit in the above communication device.

It should also be understood that the transceiver 830 may include a receiver (or receiver) and a transmitter (or transmitter). The transceiver may further include an antenna, and the number of antennas may be one or more. The transceiver may also be a communication interface or interface circuit.

Specifically, the communication device 800 may correspond to the devices (terminal device, first network device, second network device) in Figures 4 to 6 according to the embodiments of the present application. The communication device 800 may include a unit of the method performed by the terminal device in Figures 4 to 6, or a unit of the method performed by the first network device, or a unit of the method performed by the second network device. It should be understood that the specific process of each unit performing the above corresponding steps has been described in detail in the above method embodiment, and for the sake of brevity, it will not be repeated here.

When the communication device 800 is a chip, the chip includes an interface unit and a processing unit, wherein the interface unit may be an input/output circuit or a communication interface; and the processing unit may be a processor or a microprocessor or an integrated circuit integrated on the chip.

In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software modules in a processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

It should be noted that the processor in the embodiment of the present application can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method embodiment can be completed by the hardware integrated logic circuit in the processor or the instructions in software form. The above processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The various methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor for execution, or can be executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a random access memory, a flash memory, The storage medium is a mature storage medium in the field such as a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

The present application also provides a computer-readable medium on which a computer program is stored. When the computer program 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.

In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can 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 can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can 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. 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 high-density digital video disc (DVD)), or a semiconductor medium (e.g., a solid state disk (SSD)), etc.

Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software 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.

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

In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can 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, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network 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.

If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

The terms "component", "module", "system", etc., used in this specification are used to refer to computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, and/or a computer. By way of illustration, both an application running on a computing device and a computing device can be a component. One or more components can reside in a process and/or an execution thread, and a component can be located on one computer and/or distributed between two or more computers. In addition, these components can be from various computers with various data structures stored thereon. Components may communicate, for example, via local and/or remote processes based on signals having one or more data packets (e.g., data from two components interacting with another component across a local system, a distributed system, and/or a network, such as the Internet interacting with other systems via signals).

Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software 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.

Claims (23)

A communication method, characterized by comprising: The terminal device sends first information to the first network device, where the first information includes a positional relationship between the terminal device and a coverage area corresponding to a second cell, where the second cell is a cell corresponding to the second network device; The terminal device receives second information from the first network device, where the second information includes a triggering condition for conditional handover CHO, and the triggering condition for CHO is determined according to the first information; The terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of the CHO, Among them, the first network device is the network device corresponding to the first cell, the first cell is the cell corresponding to the non-terrestrial network NTN, the first network device is the source service network device of the terminal device, the second network device is the target service network device of the terminal device, and the second cell is the cell corresponding to the terrestrial network TN. The method according to claim 1, wherein the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of the CHO, comprising: The terminal device determines that the triggering condition of the CHO is satisfied, and the terminal device determines to switch from the first network device to the second network device, The triggering condition of the CHO is: the terminal device determines that the signal quality of the second reference signal is higher than a first threshold, and the terminal device is located within the coverage range corresponding to the second cell, and the second reference signal is a reference signal of the second cell. The method according to claim 1, wherein the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of the CHO, comprising: The terminal device determines that the triggering condition of the CHO is satisfied, and the terminal device determines to switch from the first network device to the second network device, The triggering condition of the CHO is: the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the first distance is less than or equal to the second threshold, or the triggering condition of the CHO is: the terminal device determines that the signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage range corresponding to the second cell, and the second distance is greater than or equal to a third threshold, Among them, the first distance is the relative distance between the terminal device and the second reference point, the second reference point is the reference point of the coverage area corresponding to the second cell, and the second distance is the distance between the position of the terminal device and the edge of the coverage area corresponding to the second cell. The method according to any one of claims 1 to 3, characterized in that before the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of the CHO, the terminal device is located within the coverage corresponding to the second cell, and the method further comprises: The terminal device sends first request information to the first network device, where the first request information is used to request measurement and/or reported configuration information corresponding to the radio resource management RRM, and the measurement and/or reported configuration information corresponding to the RRM is used by the terminal device to measure the second cell; The terminal device receives measurement and/or reporting configuration information corresponding to the RRM of the first network device. The method according to claim 4 is characterized in that, when the terminal device determines, according to the measurement and/or reporting configuration information corresponding to the RRM, that the signal quality of the second reference signal is higher than the first threshold, the method further comprises: The terminal device sends second request information to the first network device, where the second request information is used to request the first network device for configuration resource information of the second cell, The second reference signal is a reference signal of the second cell. The method according to claim 5, characterized in that the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of the CHO, comprising: When the signal quality of the second reference signal is higher than a fourth threshold, the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of the CHO, and the fourth threshold is greater than or equal to the first threshold. The method according to claim 1, wherein the terminal device determines whether to switch from the first network device to the second network device according to the triggering condition of the CHO, comprising: The terminal device determines that the triggering condition of the CHO is not satisfied, and the terminal device does not switch from the first network device to the Second network device, The terminal device is located within the coverage area corresponding to the second cell, and the distance between the terminal device and the second reference point is greater than or equal to a fifth threshold; or, the terminal device is located within the coverage area corresponding to the second cell, the distance between the terminal device and the second reference point is greater than or equal to the fifth threshold, and the speed of the terminal device is greater than or equal to a first value; or, the signal quality of the second reference signal is greater than or equal to the first threshold, and the difference between the signal quality of the second reference signal and the signal quality of the first reference signal is greater than or equal to a second value and less than or equal to a third value, the second value is less than or equal to the third value, and the second value is a positive integer; or, the signal quality of the second reference signal is greater than or equal to the first threshold, and the difference between the signal quality of the second reference signal and the signal quality of the first reference signal is less than the second value; or, the signal quality of the second reference signal is less than the first threshold, The first reference signal is a reference signal of the first cell, and the second reference signal is a reference signal of the second cell. The method according to any one of claims 2 to 7 is characterized in that the first threshold is the signal quality of the first reference signal, and the first reference signal is a reference signal of the first cell. The method according to any one of claims 1 to 8, characterized in that the method further comprises: The terminal device sends third request information to the first network device, where the third request information is used to request the first network device for configuration resource information of the second cell; The terminal device receives radio resource measurement RRC configuration information from the first network device, where the RRC configuration information includes a triggering condition for the conditional handover CHO; The terminal device sends RRC configuration completion information to the first network device. The method according to claim 9 is characterized in that the third request information includes identification information of the coverage area corresponding to the second cell. A communication method, characterized by comprising: The first network device receives first information from the terminal device, where the first information includes a positional relationship between the terminal device and a coverage area corresponding to a second cell, where the second cell is a cell corresponding to the second network device; The first network device sends second information to the terminal device, where the second information includes a triggering condition for conditional handover CHO, and the triggering condition for CHO is determined according to the first information; Among them, the first network device is the network device corresponding to the first cell, the first cell is the cell corresponding to the non-terrestrial network NTN, the first network device is the source service network device of the terminal device, the second network device is the target service network device of the terminal device, and the second cell is the cell corresponding to the terrestrial network TN. The method according to claim 11, characterized in that the triggering condition of CHO includes one or more of the following: The signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage area corresponding to the second cell, and the second reference signal is a reference signal of the second cell; The signal quality of the second reference signal is higher than the first threshold, and the first distance is less than or equal to the second threshold, the first distance is a relative distance between the terminal device and a first reference point, and the first reference point is a reference point of a coverage area corresponding to the second cell; The signal quality of the second reference signal is higher than the first threshold, and the terminal device is located within the coverage range corresponding to the second cell, the second distance is greater than or equal to the third threshold, and the second distance is the distance between the location of the terminal device and the edge of the coverage area corresponding to the second cell. The method according to claim 11 or 12, characterized in that the terminal device is located within the coverage area corresponding to the second cell, and the method further comprises: The first network device receives first request information from the terminal device, where the first request information is used to request measurement and/or reporting configuration information corresponding to a radio resource management RRM, and the measurement and/or reporting configuration information corresponding to the RRM is used by the terminal device to measure the second cell; The measurement and/or reporting configuration information corresponding to the RRC sent by the first network device to the terminal device. The method according to claim 13, characterized in that, when the signal quality of the second reference signal is higher than the first threshold, the method further comprises: The first network device receives second request information from the terminal device, where the second request information is used to request configuration resource information of the second cell. The second reference signal is a reference signal of the second cell. The method according to claim 13 or 14, characterized in that the method further comprises: The first network device sends a switching request to the second network device, where the switching request is used to request the second network device to reserve a switching resource for the terminal device. The method according to any one of claims 12 to 15 is characterized in that the first threshold is the signal quality of the first reference signal, and the first reference signal is a reference signal of the first cell. The method according to any one of claims 11 to 16, characterized in that the method further comprises: The first network device receives third request information from the terminal device, where the third request information is used by the terminal device to request the first network device for configuration resource information of the second cell; The first network device sends radio resource measurement RRC configuration information to the terminal device according to the third request information, where the RRC configuration information includes a triggering condition for the conditional handover CHO; The first network device receives RRC configuration completion information from the terminal device. The method according to claim 17 is characterized in that the third request information includes identification information of the coverage area corresponding to the second cell. A communication device, characterized in that the communication device comprises a unit or module for executing the method as described in any one of claims 1-10, 11-18. A communication device, comprising: A processor, the processor is coupled to a memory, and the processor is used to call computer program instructions stored in the memory to execute the method according to any one of claims 1-10, or the method according to any one of claims 11-18. A chip, characterized in that it includes a processor and a communication interface, wherein the communication interface is used to receive data and/or information and transmit the received data and/or information to the processor, and the processor processes the data and/or information to execute the method as described in any one of claims 1-10, or the method as described in any one of claims 11-18. A computer-readable storage medium, characterized in that instructions are stored on the computer-readable storage medium, and when the instructions are executed on a computer, the computer executes the method as described in any one of claims 1-10, or the computer executes the method as described in any one of claims 11-18. A computer program product, characterized in that instructions are stored on the computer-readable storage medium, and when the instructions are executed on a computer, the computer executes the method as described in any one of claims 1 to 10, or the computer executes the method as described in any one of claims 11 to 18.