CN111556536B

CN111556536B - BWP handover method and communication device

Info

Publication number: CN111556536B
Application number: CN201910110322.4A
Authority: CN
Inventors: 温容慧; 黎超; 张兴炜
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-02-11
Filing date: 2019-02-11
Publication date: 2021-10-01
Anticipated expiration: 2039-02-11
Also published as: WO2020164355A1; CN111556536A

Abstract

The application provides a BWP switching method and a communication device, which can solve the problem of interruption of intra-group communication of a terminal device group in the BWP switching process, thereby improving the reliability of intra-group communication of the terminal device. The method is applied to a first terminal device in a terminal device group supporting multi-BWP, the terminal device group further comprising a second terminal device. The method comprises the following steps: the first terminal device is able to complete the measurement of the target BWP while maintaining communication with the second terminal device on the source BWP, then determine that the group of terminal devices needs to be handed over from the source BWP to the target BWP based on the measurement of the target BWP, and instruct the second terminal device to communicate with the first terminal device on the target BWP. The method is suitable for BWP switching of the terminal device group in a switching scene, a moving-out scene or a moving-in scene.

Description

BWP switching method and communication device

Technical Field

The present application relates to the field of communications, and in particular, to a BWP switching method and a communications apparatus.

Background

Currently, a plurality of terminal devices, such as a mobile phone and a vehicle-mounted terminal, may form a terminal device group, and establish a Sidelink (SL) on the same bandwidth part (BWP) so as to implement direct intra-group communication. For example, when a terminal device group is in the coverage area of the same network device, the terminal device group may establish a sidelink according to the BWP configured by the network device. For another example, when the terminal device group is in a network uncovered area, the terminal device group may establish a sidelink according to a pre-configured (pre-configured) BWP.

However, when different terminal devices in the group are in different network coverage areas during the movement of the terminal device group, BWPs configured by the different terminal devices in the group are also different, which results in interruption of direct communication in the group and poor reliability. For example, in the cell handover process, a part of the terminal devices have entered the coverage area of the target network device, and the configured BWP is the BWP corresponding to the target network device, while other terminal devices are still in the coverage area of the source network device, and the configured BWP is the BWP corresponding to the source network device. For another example, in the process that the terminal device group moves out of or into the network coverage area, the BWP configured by the terminal device in the network coverage area is the BWP corresponding to the network device, and the BWP configured by the terminal device in the network uncovered area is the pre-configured BWP.

Disclosure of Invention

The application provides a BWP switching method and a communication device, which can solve the problem of interruption of intra-group direct communication of a terminal device group in the process of switching BWP, or reduce the interruption duration of intra-group direct communication of the terminal device group in the process of switching BWP, thereby improving the reliability of intra-group communication of the terminal device.

In a first aspect, a BWP handover method is provided. The method is applicable to a first terminal device in a terminal device group; the group of terminal devices further includes a second terminal device, and the group of terminal devices supports a multi BWP mode. The BWP switching method includes: the first terminal device measures the target BWP while communicating with the second terminal device over the source BWP, and determines that the group of terminal devices needs to be handed over from the source BWP to the target BWP based on the measurement of the target BWP. Then, the first terminal device sends a first handover instruction to the second terminal device on the source BWP. Wherein the first handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP. The first end-point device then communicates with the second end-point device on the target BWP and on the source BWP.

According to the BWP handover method provided by the application, the first terminal device can complete the measurement of the target BWP while maintaining the communication with the second terminal device on the source BWP, then determine that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP, and then instruct the second terminal device to communicate with the first terminal device on the target BWP on the source BWP, the problem of communication interruption in the terminal device group caused by inconsistent time for switching different terminal devices in the terminal device group to the target BWP in the process of cell switching or entering or exiting the coverage area of a wireless network can be solved, and the reliability of communication in the terminal device group during the switching of the BWP can be improved.

In one possible design method, the first switching instruction includes configuration information of the target BWP.

Optionally, the first switching instruction may further include: the second terminal device starts the start time of the target BWP. The boot target BWP refers to data communication over the BWP.

Further, the first switching instruction may further include: a stop time for the second end-device to stop communicating with the first end-device on the source BWP.

In a possible design method, the BWP switching method may further include: after the first end-point device communicates with the second end-point device on the target BWP and on the source BWP, the first end-point device stops communicating with the second end-point device on the source BWP in order to reduce the power consumption of the first end-point device.

In a second aspect, a BWP switching method is provided. The method is applicable to a first terminal device in a terminal device group; the terminal device group further includes a second terminal device, and the terminal device group supports only the single BWP mode. The single BWP mode means that only one BWP can be activated, i.e. communication is only on one BWP, at the same time and/or on the same carrier. The BWP switching method includes: the first end-point device communicates with the second end-point device over the source BWP. Then, the first terminal device switches from the source BWP to the target BWP, measures the target BWP, and determines that the terminal device group needs to switch from the source BWP to the target BWP according to the measurement result of the target BWP. Thereafter, the first terminal device switches back to the source BWP and sends a second switch instruction to the second terminal device on the source BWP. Wherein the second handover instruction is used to instruct the second terminal device to handover from the source BWP to the target BWP. Finally, the first end-device switches from the source BWP to the target BWP again and communicates with the second end-device on the target BWP.

According to the BWP handover method provided by the present application, after the first terminal device completes the measurement of the target BWP after the handover from the source BWP to the target BWP, if the first terminal device determines that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP, the switch-back to the source BWP sends the second handover instruction to the second terminal device, which instructs the second terminal device to communicate with the second terminal device on the handover from the source BWP to the target BWP, so that the inter-terminal-device-group communication interruption duration caused by the large time deviation of the different terminal devices in the terminal device group to the target BWP during the cell handover or the entering or exiting of the coverage area of the wireless network can be effectively reduced, thereby improving the reliability of inter-terminal-device-group communication during the handover of the BWP.

In one possible design method, the second handover command includes a first handover time, and the first handover time is a time when the second terminal device is handed over from the source BWP to the target BWP. Accordingly, the aforementioned switching of the first terminal device from the source BWP to the target BWP again may include: the first terminal device switches from the source BWP to the target BWP again at a second switch time. And the time deviation between the first switching time and the second switching time is smaller than a time deviation threshold value, so that the communication interruption time of the terminal device group in the process of switching from the source BWP to the target BWP is reduced, and the reliability of communication in the terminal device group is further improved.

In one possible design method, the second handover command further includes configuration information of the target BWP.

In a possible design method, the BWP switching method may further include at least one of the following: in the process of measuring the target BWP by the first terminal device, the first terminal device communicates with the second terminal device through the network device; in the process of switching the first end device from the source BWP to the target BWP, the first end device communicates with the second end device through the network device.

In a possible design method, the BWP switching method according to the first aspect or the second aspect may further include one of the following: a first terminal device receives a measurement task of a target BWP sent by a source network device or a target network device; and the first terminal device does not detect any wireless signal sent by the network device, and then starts the measurement task of the target BWP by itself.

In a third aspect, a BWP switching method is provided. The method is applicable to the source network device. The BWP switching method includes: the source network device receives the measurement result of the target BWP sent by the first terminal device, and determines that the terminal device group needs to be switched from the source BWP to the target BWP according to the measurement result of the target BWP. The first terminal equipment belongs to a terminal equipment group, and the terminal equipment group further comprises second terminal equipment. Then, the source network device sends a third switching instruction to the terminal device group. Wherein the third switching instruction is used for instructing the terminal device group to switch from the source BWP to the target BWP.

According to the BWP switching method provided by the present application, the source network device may determine that the terminal device group needs to be switched from the source BWP to the target BWP according to the measurement result of the target BWP reported by the first terminal device, and issue the third switching instruction to each terminal device in the terminal device group, so that each terminal in the terminal device group switches from the source BWP to the target BWP according to the third switching instruction, and reestablishes intra-group direct communication of the terminal device group on the sidelink SL on the target BWP, which may avoid or effectively reduce the inter-group direct communication interruption duration of the terminal device group on the sidelink SL during the cell switching or entering or exiting the coverage area of the wireless network, thereby improving the reliability of intra-group communication during BWP switching.

In one possible design method, the third handover command includes configuration information of the target BWP.

Optionally, the third switching instruction may further include: a third switching time and a fourth switching time. Wherein the third switching time is used for the first terminal device to switch from the source BWP to the target BWP again, the fourth switching time is used for the second terminal device to switch from the source BWP to the target BWP, and a time deviation between the third switching time and the fourth switching time is less than the time deviation threshold.

Optionally, the BWP switching method may further include: the source network device sends the measurement task of the target BWP to the first end device.

In the foregoing first aspect to the third aspect, or any possible implementation manner of the first aspect to the third aspect, the determining, according to the measurement result of the target BWP, that the group of terminal devices needs to be handed over from the source BWP to the target BWP may include: if the measurement result of the target BWP satisfies the BWP handover condition, it is determined that the terminal device group needs to be handed over from the source BWP to the target BWP.

Wherein the BWP switching condition includes at least one of: the signal strength of the target BWP is above the BWP signal strength threshold; the signal quality of the target BWP is above the SL signal quality threshold; the continuous duration of which the free resource occupancy on the source BWP is higher than the first occupancy threshold is greater than a first duration threshold; the continuous duration of which the free resource occupancy on the target BWP is lower than the second occupancy threshold is greater than the second duration threshold; the continuous duration that the number of free resources on the source BWP is less than the number of free resources on the target BWP is greater than a third duration threshold; there is no traffic on the source BWP with a priority above the priority threshold.

In a fourth aspect, a communication device is provided. The device is suitable for the first terminal equipment in the terminal equipment group. Wherein the terminal device group further includes a second terminal device, and the terminal device group supports a multi BWP mode. The communication apparatus of the fourth aspect includes: the device comprises a first communication module, a second communication module and a control module. Wherein the first communication module is configured to communicate with the second terminal device on the source BWP. A control module, configured to control the second communication module to measure the target BWP while the first communication module communicates with the second terminal device on the source BWP, and determine that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP. The first communication module is further configured to send a first handover instruction to the second terminal device on the source BWP. Wherein the first handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP. And a second communication module for communicating with a second terminal device on the target BWP.

In one possible design, the first switching instruction includes configuration information of the target BWP.

Optionally, the first switching instruction may further include: the second terminal device starts the start time of the target BWP.

In one possible design, the communication device may further include: and a third communication module. The third communication module is configured to receive a measurement task of the target BWP sent by the source network device. Correspondingly, the control module is further configured to control the second communication module to start the measurement task of the target BWP by itself if the third communication module does not detect any wireless signal sent by the network device. And the third communication module is further configured to receive a measurement task of the target BWP sent by the target network device.

In one possible design, after the first communication module and the second communication module communicate with the second terminal device on the target BWP and the source BWP, respectively, the control module may further be configured to: the first communication module is controlled to stop communicating with the second terminal device on the source BWP in order to reduce power consumption of the first terminal device.

In a fifth aspect, another communication apparatus is provided. The device is suitable for the first terminal equipment in the terminal equipment group. Wherein the terminal device group further includes a second terminal device, and the terminal device group supports only the single BWP mode. The communication device includes: a fourth communication module and a control module. Wherein, the fourth communication module is configured to communicate with the second terminal device on the source BWP. And the control module is used for controlling the fourth communication module to switch from the source BWP to the target BWP, measure the target BWP, and determine that the terminal device group needs to be switched from the source BWP to the target BWP according to the measurement result of the target BWP. And the control module is further configured to control the fourth communication module to switch back to the source BWP at the second switching time and to communicate with the second terminal device at the target BWP after controlling the fourth communication module to switch back to the source BWP and send the second switching instruction to the second terminal device at the source BWP. Wherein the second handover instruction is used for instructing the second terminal device to handover from the source BWP to the target BWP at a first handover time, and a time deviation between the first handover time and the second handover time is smaller than a time deviation threshold.

In one possible design, the second handover instruction includes a first handover time, and the first handover time is a time when the second terminal device is handed over from the source BWP to the target BWP. Accordingly, the control module is further configured to control the fourth communication module to switch from the source BWP to the target BWP again at the second switching time. Wherein a time deviation between the first switching time and the second switching time is less than a time deviation threshold.

In one possible design, the second handover command further includes configuration information of the target BWP.

In one possible design, the communication device further includes: and a fifth communication module. The fifth communication module is configured to communicate with the second terminal device through the network device during a process in which the control module controls the fourth communication module to measure the target BWP, and communicate with the second terminal device through the network device during a process in which the control module controls the fourth communication module to switch from the source BWP to the target BWP.

Optionally, the fifth communication module is further configured to receive a measurement task of the target BWP sent by the source network device or the target network device.

Optionally, the control module is further configured to control the fourth communication module to start the measurement task of the target BWP by itself if the fifth communication module does not detect a wireless signal sent by any network device.

In a sixth aspect, yet another communication apparatus is provided. The device is suitable for source network equipment. The communication device includes: a sixth communication module and a control module. The sixth communication module is configured to receive a measurement result of the target BWP sent by the first terminal device. The first terminal equipment belongs to a terminal equipment group, and the terminal equipment group further comprises second terminal equipment. And the control module is used for determining that the terminal device group needs to be switched from the source BWP to the target BWP according to the measurement result of the target BWP. And the sixth communication module is further configured to send a third switching instruction to the terminal device group. Wherein the third switching instruction is used for instructing the terminal device group to switch from the source BWP to the target BWP.

In one possible design, the third handover command includes configuration information of the target BWP.

In a possible design, the third switching instruction may further include: a third switching time and a fourth switching time. Wherein the third switching time is used for the first terminal device to switch from the source BWP to the target BWP again, the fourth switching time is used for the second terminal device to switch from the source BWP to the target BWP, and a time deviation between the third switching time and the fourth switching time is less than the time deviation threshold.

Optionally, the sixth communication module is further configured to send a measurement task of the target BWP to the first terminal device.

In the communication apparatus of the first aspect to the third aspect, or any possible implementation manner of the first aspect to the third aspect, the control module is further configured to determine that the terminal device group needs to be handed over from the source BWP to the target BWP if the measurement result of the target BWP satisfies the BWP handover condition.

In a seventh aspect, a communications apparatus is provided. The device includes: a processor and a transceiver, and the processor is coupled with the transceiver and the memory. A memory for storing a computer program. A processor configured to execute a computer program stored in a memory, to cause a communication apparatus to perform a BWP switching method according to the first aspect or any one of the possible implementations of the first aspect, or to perform a BWP switching method according to the second aspect or any one of the possible implementations of the second aspect, or to perform a BWP switching method according to the third aspect or any one of the possible implementations of the third aspect.

In an eighth aspect, a communication system is provided. The communication system includes: a plurality of terminal devices, such as the first terminal device and the second terminal device described above, and one or more network devices, such as a source network device and a target network device.

A ninth aspect provides a readable storage medium storing a program or instructions, which, when executed on a computer, causes the computer to perform the BWP switching method according to the first aspect or any one of the possible implementations of the first aspect, or perform the BWP switching method according to the second aspect or any one of the possible implementations of the second aspect, or perform the BWP switching method according to any one of the possible implementations of the third aspect or the third aspect.

A tenth aspect provides a computer program product comprising computer program code to, when run on a computer, cause the computer to perform a BWP switching method according to the first aspect or any one of the possible implementations of the first aspect, or to perform a BWP switching method according to the second aspect or any one of the possible implementations of the second aspect, or to perform a BWP switching method according to the third aspect or any one of the possible implementations of the third aspect.

Drawings

Fig. 1 is a schematic structural diagram of a communication system to which the BWP handover method provided in the present application is applied;

fig. 2A is a schematic diagram of a handover scenario to which the BWP handover method provided in the present application is applied;

fig. 2B is a schematic diagram of a shift-out scenario to which the BWP switching method provided in the present application is applied;

fig. 2C is a schematic diagram of a move-in scene to which the BWP switching method provided in the present application is applied;

fig. 3 is a first flowchart illustrating a BWP handover method according to the present application;

fig. 4 is a second flowchart illustrating a BWP handover method according to the present application;

fig. 5 is a third schematic flowchart of a BWP handover method provided in the present application;

fig. 6 is a first schematic structural diagram of a communication device according to an embodiment of the present disclosure;

fig. 7 is a second schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 8 is a third schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 9 is a fourth schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 11 is a sixth schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

The technical scheme of the embodiment of the application can be applied to various wireless communication systems with single systems: a fourth generation (4th generation, 4G) system, such as a Long Term Evolution (LTE) system, a fifth generation (5th generation, 5G) system, such as a New Radio (NR) system, a narrowband Internet of Things (NB-IoT, Narrow Band-Internet of Things) system, a vehicle networking system (telematics), a Machine Communication (MTC, Machine Type Communication) system, a future Communication system, such as a 6G system, etc., may also be applied to a multi-system wireless Communication system using two or more systems, such as a heterogeneous system using two or more systems, such as LTE and NR, which is not limited in this application.

The embodiment of the present application is described by taking an NR system as an example. It should be noted that the technical solution provided in the embodiment of the present application may also be applied to other wireless communication systems, such as the above LTE system, the car networking system, and the like, and the corresponding names may also be replaced with names of corresponding functions in other wireless communication systems.

This application is intended to present various aspects, embodiments or features around a system that may include a number of devices, components, modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, components, modules, etc. and/or may not include all of the devices, components, modules etc. discussed in connection with the figures. Furthermore, a combination of these schemes may also be used.

In addition, in the embodiments of the present application, "example", "for example" is used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary," "e.g.," is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, the term using examples is intended to present concepts in a concrete fashion.

In the embodiments of the present application, "of", "corresponding" and "corresponding" may be sometimes used in combination, and it should be noted that the intended meaning is consistent when the difference is not emphasized.

The network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not form a limitation on the technical solution provided in the embodiment of the present application, and as a person of ordinary skill in the art knows that along with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

For the convenience of understanding the embodiments of the present application, a wireless communication system applied to the embodiments of the present application will be first described in detail by taking the wireless communication system shown in fig. 1 as an example.

Fig. 1 is an architecture diagram of a mobile communication system to which an embodiment of the present application is applied. As shown in fig. 1, the mobile communication system includes a core network device, a radio access network device, and at least one terminal device (e.g., terminal device 1 and terminal device 2 in fig. 1). The terminal equipment is connected with the wireless access network equipment in a wireless mode, and the wireless access network equipment is connected with the core network equipment in a wireless or wired mode. The core network device and the radio access network device may be separate physical devices, or the function of the core network device and the logical function of the radio access network device may be integrated on the same physical device, or a physical device may be integrated with a part of the function of the core network device and a part of the function of the radio access network device. The terminal equipment may be fixed or mobile. Fig. 1 is a schematic diagram, and other network devices, such as a wireless relay device and a wireless backhaul device, may also be included in the communication system, which are not shown in fig. 1. The embodiments of the present application do not limit the number of core network devices, radio access network devices, and terminal devices included in the mobile communication system.

The radio access network device is an access device in which the terminal device is wirelessly accessed to the mobile communication system, and may be a base station NodeB, an evolved node b, a base station in a 5G mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system, and the like.

A terminal device may also be referred to as a terminal device (terminal), a User Equipment (UE), a Mobile Station (MS), a mobile terminal device (MT), etc. The terminal device may be a mobile phone (mobile phone), a tablet computer (Pad), a computer with a wireless transceiving function, a Virtual Reality (VR) terminal device, an Augmented Reality (AR) terminal device, a wireless terminal device in industrial control (industrial control), a wireless terminal device in self driving (self driving), a wireless terminal device in remote surgery (remote medical supply), a wireless terminal device in smart grid (smart grid), a wireless terminal device in transportation safety (transportation safety), a wireless terminal device in smart city (smart city), a wireless terminal device in smart home (smart home), and so on.

The wireless access network equipment and the terminal equipment can be deployed on land, including indoors or outdoors, and are handheld or vehicle-mounted; can also be deployed on the water surface; it may also be deployed on airborne airplanes, balloons, and satellites. The embodiment of the application does not limit the application scenarios of the wireless access network device and the terminal device.

The embodiments of the present application may be applicable to downlink signal transmission, may also be applicable to uplink signal transmission, and may also be applicable to device-to-device (D2D) signal transmission. For downlink signal transmission, the sending device is a radio access network device, and the corresponding receiving device is a terminal device. For uplink signal transmission, the transmitting device is a terminal device, and the corresponding receiving device is a radio access network device. For D2D signaling, the sending device is a terminal device and the corresponding receiving device is also a terminal device. The embodiment of the present application does not limit the transmission direction of the signal.

The radio access network device and the terminal device, and the terminal device may communicate via a licensed spectrum (licensed spectrum), may communicate via an unlicensed spectrum (unlicensed spectrum), and may communicate via both the licensed spectrum and the unlicensed spectrum. The radio access network device and the terminal device may communicate with each other through a spectrum of 6G or less, may communicate through a spectrum of 6G or more, and may communicate using both a spectrum of 6G or less and a spectrum of 6G or more. The embodiments of the present application do not limit the spectrum resources used between the radio access network device and the terminal device.

It should be understood that fig. 1 is a simplified schematic diagram of an example for ease of understanding only, and that other network devices or other terminal devices may also be included in the communication system, which are not shown in fig. 1.

In order to meet the requirements of high system capacity and high data rate, network devices of a wireless communication system, such as g nodes (gnbs) in an NR system, usually need to support a large bandwidth, such as 100 megahertz (MHz) and 200MHz, and terminal devices usually do not need to support a bandwidth of the same size as the network devices. For example, the end device may only need to support 40MHz, 60MHz bandwidth to meet the communication requirements. Therefore, a partial bandwidth (BWP, also called a bandwidth part) is introduced on an Uplink (UL)/Downlink (DL) between the terminal device and the network device to reduce power consumption and cost of the terminal device. The partial bandwidth refers to a set of consecutive Physical Resource Blocks (PRBs) configured for the terminal device by the radio access network device. The frequency spectrum bandwidth of the set of contiguous PRBs is generally smaller than the total frequency spectrum bandwidth supported by the radio access network device.

It is easily understood that one terminal device may configure only one active BWP or may configure a plurality of active BWPs. When only one BWP is configured, a terminal device may communicate with a wireless network on the uplink and downlink using the BWP, or may directly communicate with another terminal device on a Sidelink (SL) using the BWP. When multiple BWPs are configured, a terminal device may communicate with a wireless network on an uplink and a downlink using all BWPs, may directly communicate with one or more other terminal devices on a sidelink using all BWPs, and may also communicate with one or more other terminal devices on a sidelink using a portion BWP while communicating with the wireless network on an uplink and a downlink using another portion BWP, which is not limited in this application.

For example, in a car networking application scenario, a vehicle-mounted terminal device may support various forms of vehicle-to-vehicle (V2V), vehicle-to-pedestrian (V2P), vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), and other vehicle-to-any object (V2X) communication.

Currently, if the terminal device is located in a network coverage area (in coverage), the terminal device uses a BWP corresponding to the radio access network device, such as the BWP that can be sent through Radio Resource Control (RRC) signaling or broadcast (broadcast) signaling, to directly communicate with other terminal devices on the sidelink, otherwise, uses a pre-configured BWP to directly communicate with other terminal devices on the sidelink. That is to say, the existing terminal device can only passively complete its BWP configuration according to the preconfigured BWP or the BWP issued by the network device where the terminal device is located. Wherein the pre-configured BWP may be a default BWP configured according to protocol specifications at the time of factory shipment of the terminal device.

In practical applications, a plurality of terminal devices may also form a terminal device group and coordinate with each other through intra-group communication. For example, the terminal device may be a vehicle-mounted terminal, and the terminal device group may be a vehicle-mounted terminal device group, and the actions of the vehicles in the group, such as changing the driving route, coordinating the vehicle speed and the vehicle distance, may be coordinated through the vehicle-mounted terminal device group internal communication.

As shown in fig. 2A-2C, the terminal device group includes a first terminal device, a second terminal device, and a third terminal device.

In a cell handover scenario (hereinafter referred to as a handover scenario) as shown in fig. 2A, when a terminal device group is located in a coverage area of a source network device, the terminal device group communicates on a sidelink using a source BWP configured by the source network device. After the end device group moves from the coverage area of the source network device into the coverage area of the target network device, the end device group communicates on the sidelink using the target BWP configured by the target network device.

In a move-out network coverage scenario (hereinafter referred to as a move-out scenario) as shown in fig. 2B, after the group of terminal devices moves out of the network coverage area into the network uncovered area, for example, moves out of the coverage area of the source network device into an area without the coverage of the network device, the group of terminal devices communicates on the sidelink using a preconfigured BWP.

In the move-into-network coverage scenario (hereinafter referred to as the move-into scenario) shown in fig. 2C, when the terminal device group is out of network coverage (OOC), the terminal device group communicates on the sidelink using the preconfigured BWP. After the group of end devices moves from the network uncovered area to the target network device covered area, the group of end devices communicates on the sidelink using the target BWP configured by the target network device.

However, the time for completing the new BWP configuration in the above 3 scenarios is usually different for different end devices in the end device group. Therefore, when one part of the terminal devices is configured as a new BWP and another part of the terminal devices is still using the original BWP, and when the new BWP is different from the original BWP, the two parts of the terminal devices may have a long interruption of communication on the sidelink, thereby adversely affecting the reliability of direct communication within the group of terminal devices.

The duration of the interruption of the direct communication in the terminal device group may be determined according to the moving speed of the terminal device group and the distance between the terminal device that first completes the new BWP configuration and the terminal device that last completes the new BWP configuration. For example, as shown in fig. 2A, assuming that the terminal device groups are all vehicle-mounted terminal devices with a moving speed of 100 kilometers per hour (km/h), and the first terminal device, the second terminal device, and the third terminal device are sequentially spaced by 100 meters (safe vehicle distance), the distance between the first terminal device and the third terminal device is 200 meters, and the communication interruption time is about as long as: 200/(100 × 1000/3600) ═ 7.2 seconds (second, s), that is, the communication interruption time in the terminal device group is longer, and there is a higher driving safety risk.

In view of the above problems, the embodiments of the present application provide three BWP switching methods. The following description is made separately with reference to the accompanying drawings.

Fig. 3 is a flowchart illustrating a first BWP handover method according to an embodiment of the present application, which may be applied to the wireless communication system shown in fig. 1 to solve the problem of interruption of direct communication in a terminal device group in any of the scenarios shown in fig. 2A to fig. 2C, so as to improve reliability of direct communication in the terminal device group.

The terminal device group comprises a first terminal device, a second terminal device and a third terminal device, and the terminal device group supports a multi-BWP mode.

The aforementioned terminal device group supporting the multi-BWP mode means that each terminal device in the terminal device group supports direct communication with other terminal devices in the terminal device group over 2 BWPs or more than 2 BWPs. For example, each terminal device is configured with 2 or more than 2 independently controllable communication units, such as 2 sets or more than 2 sets of radio frequency circuits, and each communication unit can independently support a BWP.

The first BWP switching method provided in the embodiment of the present application is described in detail below with reference to a first terminal device and a second terminal device as examples.

As shown in fig. 3, the first BWP switching method may include S301-S305:

s301, the first end-point device communicates with the second end-point device over the source BWP.

Optionally, for the handover scenario shown in fig. 2A or the move-out scenario shown in fig. 2B, the source BWP is the BWP corresponding to the source network device. Specifically, when the terminal device group is in the coverage area of the source network device, the source network device issues the configuration information of the source BWP through RRC signaling of the Uu port. Each terminal device in the terminal device group establishes intra-group direct communication on the sidelink SL according to the configuration information of the source BWP.

Optionally, for the move-in scenario as shown in fig. 2C, the source BWP is a pre-configured BWP. Specifically, the pre-configured BWP may be the same BWP that is pre-configured according to protocol specifications at the time of factory shipment of the terminal device. When the terminal device group is located in the network uncovered area, each terminal device in the terminal device group establishes intra-group direct communication on the sidelink SL according to the configuration information of the preconfigured BWP.

Illustratively, the configuration information of the source BWP may include at least one of: BWP identification of the source BWP, carrier frequency and bandwidth of the source BWP, carrier interval used on the BWP, BWP activation time, BWP deactivation time, and resource identification of the shared resource on the source BWP, etc.

S302, the first terminal device measures a target BWP.

Optionally, for the handover scenario shown in fig. 2A or the move-in scenario shown in fig. 2C, the target BWP refers to the BWP corresponding to the target network device. When the end device group is in the target network device coverage area, the end device group needs to establish intra-group direct communication on the sidelink SL on the target BWP.

Alternatively, for a move-out scenario as shown in fig. 2B, the target BWP refers to a pre-configured BWP. When the group of terminal devices is in a network uncovered area, the group of terminal devices needs to establish intra-group direct communication on the sidelink SL on a preconfigured BWP.

Of course, there may be one or more target BWPs, and the target BWPs are not limited herein. For example, for a handoff scenario as shown in fig. 2A, when there are multiple neighbors, there may be multiple target BWPs.

Illustratively, the measurement task of the target BWP may include configuration information of one or more target BWPs. Specifically, at least one of the following may be included:

a physical cell identifier list (PCID list) of the target cell;

a target BWP associated PCID list (sidelink BWP associated PCID list) corresponding to each target cell;

SL resource pools (sidelink resource pool with BWP) on each target BWP;

a measurement period for each target BWP;

uu port signal threshold for target BWP switching/opening/closing (Uu-RSRP threshold for sidelink BWP switching/open/close);

SL signal threshold for target BWP switching/on/off (SL-RSRP threshold for sidelink BWP switching/open/close).

The Uu port signal threshold may include at least one of a Uu port signal strength threshold and a Uu port signal quality threshold, such as a Uu port reference signal received power (Uu-RSRP) threshold and a Uu port reference signal received quality (Uu-RSRP) threshold. Similarly, the signal threshold on the SL may also include at least one of a signal strength threshold on the SL and a signal quality threshold on the SL, such as an RSRP threshold on the SL, an RSRQ threshold on the SL, and so on.

The measurement task of the target BWP may be periodically or triggered by a network event. Thus, in one possible design approach, the first terminal device may periodically initiate measurements of the target BWP according to a measurement period carried by the measurement task. It is to be understood that the measurement period of the target BWP may be the same as or different from the measurement period of the serving cell/neighbor cell, and the present application is not limited thereto.

In another possible design approach, the first terminal device may also initiate measurement of the target BWP based on measurement initiation conditions.

Wherein the measurement start condition may include at least one of:

the method comprises the steps that a first terminal device detects that a network signal sent by a source network device is smaller than a source network signal threshold value;

the method comprises the steps that a first terminal device detects that a network signal sent by a target network device is larger than a target network signal threshold value;

the first terminal equipment detects that the difference value between a network signal sent by target network equipment and a network signal sent by source network equipment is greater than a signal deviation threshold value;

all network signals detected by the first terminal equipment are smaller than a network signal threshold value;

the sidelink SL signal detected by the first terminal device is less than the SL signal threshold.

Further, the detecting, by the first terminal device, all network signals smaller than the network signal threshold may include: the first terminal device does not detect the network signal, and the first terminal device is already in a network uncovered area.

It should be noted that the network signal threshold may be a signal strength threshold, such as a Uu-RSRP threshold described in S302, or a signal quality threshold, such as an SL-RSRQ threshold described in S302, which is not limited herein.

It is to be easily understood that, before the first terminal device measures the target BWP in step S302, the first BWP switching method may further include one of the following steps:

a first terminal device receives a measurement task of a target BWP issued by a source network device;

a first terminal device receives a measurement task of a target BWP issued by a target network device;

the first terminal device starts the measurement task of the pre-configured target BWP by itself.

Optionally, for the handover scenario shown in fig. 2A and the move-out scenario shown in fig. 2B, the first terminal device receives a measurement task of the target BWP, which is issued by the source network device through RRC signaling on the Uu link.

Optionally, for the move-in scenario shown in fig. 2C, after the first terminal device enters the coverage area of the target network device, the measurement task of the target BWP, which is delivered by the target network device through RRC signaling on the Uu link, is received.

S303, the first terminal device determines, according to the measurement result of the target BWP, that the terminal device group needs to be handed over from the source BWP to the target BWP.

Specifically, the step S304 of determining that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP may be specifically implemented as:

if the measurement result of the target BWP satisfies the BWP handover condition, it is determined that the terminal device group needs to be handed over from the source BWP to the target BWP.

Wherein the BWP handover condition may include at least one of the following:

the signal quality of the target BWP is above the SL signal quality threshold;

the signal strength of the target BWP is above the SL signal strength threshold;

the continuous duration of which the idle resource occupancy (idle resource ratio) on the source BWP is higher than the first occupancy threshold is larger than the first duration threshold;

the continuous duration of which the free resource occupancy on the target BWP is lower than the second occupancy threshold is greater than the second duration threshold;

the continuous duration that the number of free resources on the source BWP is less than the number of free resources on the target BWP is greater than a third duration threshold;

there is no traffic on the source BWP with a priority above the priority threshold.

The free resource occupation ratio on the source BWP refers to the ratio of the number of free resources, such as free RBs, on the source BWP to the total amount of resources on the source BWP. Similarly, the free resource occupation ratio of the target BWP refers to a ratio of the number of free resources, such as free RBs, on the target BWP to the total amount of resources on the target BWP.

The above-mentioned idle resource occupancy on the source BWP being higher than the first occupancy threshold means that the number of terminal devices operating on the source BWP is smaller, meaning that most of the terminal devices in the group of terminal devices may have been handed over to the target BWP or that the terminal device has moved away from the source cell and is therefore further away from other terminals communicating on the source BWP in the source cell. The first terminal device also needs to switch to the target BWP as soon as possible in order to keep consistent with other terminals in the group or to communicate with other terminal devices that are in close proximity. Wherein the first duty threshold is generally configured to be a larger value, such as 80%, 70%, etc.

The above-mentioned idle resource occupancy on the target BWP being lower than the second occupancy threshold means that the number of terminal devices operating on the target BWP is larger, which means that most terminal devices in the terminal device group have switched to the target BWP. In order to keep pace with the other terminals in the group, the first terminal device also needs to switch to the target BWP as soon as possible. Wherein the second percentage threshold is generally configured to be a small value, such as 20%, 30%, etc.

The above-mentioned number of free resources on the source BWP is smaller than that on the target BWP, which means that the system capacity of the target BWP is higher than that of the original BWP. Therefore, in order to accommodate more terminal devices, each terminal device in the group of terminal devices, such as the first terminal device, needs to switch from the source BWP to the target BWP as soon as possible.

It should be noted that, in order to ensure the stability and reliability of the handover decision and avoid ping-pong handover, the statistical duration that the free resource occupancy on the source BWP is higher than the first occupancy threshold, the statistical duration that the free resource occupancy on the target BWP is lower than the second occupancy threshold, and the statistical duration that the number of free resources on the source BWP is greater than the number of free resources on the target BWP are all continuous durations. In addition, the first time length threshold, the second time length threshold, and the third time length threshold all need to be set to a larger value, such as 10 slots (slots), 100 milliseconds, and the like. It is easy to understand that the above 3 time length thresholds may be the same or different, and the application does not limit this.

The service priority may be determined comprehensively according to multiple factors such as the speed requirement, the delay requirement, and the error rate requirement of the service, which are not described herein again.

S304, the first terminal device sends a first switching instruction to the second terminal device on the source BWP.

Wherein the first handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP.

Illustratively, the Physical Cell Identifier (PCID) of the target cell;

target BWP (sidelink BWP associated pcid) corresponding to the target cell;

SL resource pools (sidelink resource pool with BWP) on the target BWP.

The target BWP included in the first handover instruction may be configuration information of one target BWP in configuration information carried in the measurement task, or may be a target BWP that is not carried in the measurement task but is detected by the first terminal and satisfies the BWP handover condition, which is not limited in this application.

Alternatively, the first terminal device may send the first handover command to the second terminal device on a control channel on the sidelink SL, for example, a Physical Sidelink Control Channel (PSCCH), or may send the first handover command to the second terminal device on a data channel on the sidelink SL, for example, a physical sidelink shared channel (PSCCH), which is not limited in this application.

Optionally, for the handover scenario shown in fig. 2A and the move-out scenario shown in fig. 2B, S304 the first terminal device sends the first handover instruction to the second terminal device on the source BWP, which may be replaced with the following steps:

the first terminal equipment reports the first switching instruction to the source network equipment through the Uu port.

And then, the source network equipment issues a first switching instruction to other terminal equipment in the terminal equipment group, such as second terminal equipment, through the Uu port.

Similarly, for the move-in scenario shown in fig. 2B, S304 the first terminal device sends the first switch instruction to the second terminal device on the source BWP, which may be replaced with the following steps:

and the first terminal equipment reports the first switching instruction to the target network equipment through the Uu port.

After the coverage area of other terminal devices in the terminal device group, such as a target network device, the target network device issues a first switching instruction to the other terminal devices in the terminal device group, such as a second terminal device, through the Uu port.

It should be noted that the start time may be a start time directly carried by the first switching instruction, or may be a start time determination rule carried by the first switching instruction, which is not limited in this application.

Alternatively, the second terminal device may initiate communication on the target BWP immediately after receiving the first handover instruction.

Alternatively, the second terminal device may also initiate communication on the target BWP after delaying for a specified duration after receiving the first handover instruction.

Optionally, the second terminal device may also determine the start time of the target BWP according to the measurement result of the source BWP and the target BWP by the second terminal device.

Optionally, the second terminal device may also convert the start time of the target BWP corresponding to the second terminal device according to the channel measurement result of the sidelink SL with the first terminal device.

S305, the first end-point device communicates with the second end-point device on the target BWP and on the source BWP.

Specifically, the second terminal device initiates measurement and communication on the target BWP upon receiving the first handover instruction. To this end, a sidelink SL on the source BWP and a sidelink SL on the target BWP are simultaneously established between the first terminal device and the second terminal device. That is, there is a dual connection between the first terminal device and the second terminal device. It is understood that the intra-group information may be transmitted on the source BWP, the target BWP, or both the source BWP and the target BWP, which is not limited herein.

It is readily understood that after the communication between the second end-point device and the first end-point device on the target BWP is established, the first end-point device may also disconnect the direct communication with the second end-point device on the source BWP in order to reduce the power consumption of the first end-point device. Therefore, the BWP switching method one may further include the following steps:

the first end-point device stops communicating with the second end-point device on the source BWP.

Accordingly, after the second terminal device establishes communication with the first terminal device on the target BWP, the second terminal device may also disconnect its direct communication with the first terminal device on the source BWP in order to reduce power consumption of the second terminal device. Therefore, further, the first switching instruction may further include: stop time for the second end-device to stop communicating directly with the first end-device on the source BWP.

Alternatively, the second end-point device may set a local timer (timer) that expires before the first end-point device disconnects its communication with the first end-point device on the source BWP.

Optionally, the second terminal device may also determine when to disconnect the measurement link SL between the first terminal device and the source BWP based on the mobility measurement results of the source BWP and the target BWP.

It is easy to understand that the terminal device group may further include other terminal devices, such as a third terminal device. The operation of the third terminal device may refer to the related description of the second terminal device, and is not described herein again.

According to the first BWP handover method provided by the present application, the first terminal device is able to complete the measurement of the target BWP while maintaining communication with the second terminal device on the source BWP, and then determine that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP, and then instruct the second terminal device to communicate with the first terminal device on the target BWP on the source BWP, so as to solve the problem of communication interruption in the terminal device group caused by inconsistent time for different terminal devices in the terminal device group to handover to the target BWP during the cell handover or entering or exiting the coverage area of the wireless network, thereby improving the reliability of communication in the terminal device group during BWP handover.

Fig. 4 is a flowchart of a BWP handover method two according to an embodiment of the present application, which may be applied to the wireless communication system shown in fig. 1 to reduce the interruption duration of direct communication in a terminal device group in any of the scenarios shown in fig. 2A to fig. 2C, so as to improve the reliability of direct communication in the terminal device group. The terminal device group comprises a first terminal device, a second terminal device and a third terminal device, and only supports a single BWP mode.

The aforementioned terminal device group supporting the single BWP mode means that each terminal device in the terminal device group only supports direct communication with other terminal devices in the terminal device group on 1 BWP. For example, each terminal device is configured with only 1 communication unit, such as 1 set of radio frequency circuit, which can be used for the sidelink SL.

The second BWP switching method provided in the embodiment of the present application is described in detail below by taking a first terminal device and a second terminal device as examples.

As shown in fig. 4, the second BWP switching method may include S401 to S405:

s401, a first end-point device communicates with a second end-point device on a source BWP.

S401 is the same as S301, and is not described herein again.

S402, the first terminal device is switched from the source BWP to the target BWP, and measures the target BWP.

Similar to the BWP switching method, the receiving manner and the starting condition of the measurement task of the target BWP may refer to the related description in S302, and are not described herein again.

It should be noted that, in view of that the first terminal device only supports the single BWP mode, when the measurement target BWP is needed, the first terminal device needs to switch from the source BWP to the target BWP, i.e. configure the communication unit for communication on the sidelink SL in the first terminal device as the target BWP.

Therefore, during the execution of S402, the communication between the first terminal device and the other terminal devices in the terminal device group on the sidelink SL may be interrupted. In view of this, in the embodiment of the present application, the intra-group communication between the first terminal device and other terminal devices in the terminal device group, such as the second terminal device, may also be completed in a network device forwarding manner, for example, the multicast information is forwarded by the network device, so as to avoid interruption of the intra-group communication of the terminal devices.

For example, for a handover scenario as shown in fig. 2A, a first end device may exchange multicast information with other end devices within the end device group by exchanging multicast information with the target network device and the source network device.

For example, for a move-out scenario as shown in fig. 2B, the first end device may exchange multicast information with other end devices within the end device group by communicating with the source network device.

S403, the first terminal device determines, according to the measurement result of the target BWP, that the terminal device group needs to be handed over from the source BWP to the target BWP.

S303 may be referred to for details of S403, and details are not described herein.

S404, the first terminal device switches back to the source BWP and sends a second switching instruction to the second terminal device on the source BWP.

In view of the first terminal device supporting only the single BWP mode, the first terminal device may switch back to the source BWP and send a second switch instruction to the second terminal device on the source BWP.

Wherein the second handover instruction is used to instruct the second terminal device to handover from the source BWP to the target BWP.

In one possible design approach, the second switching command includes a first switching time. Wherein the first switching time is a time when the second terminal device switches from the source BWP to the target BWP.

It should be noted that, the first switching time may refer to the description related to the start time of the second end device start target BWP in S304 of the first BWP switching method, and is not described herein again.

In a possible design method, the second handover command may further include configuration information of the target BWP. The configuration information of the target BWP may refer to the relevant description in S304, and is not described herein again.

It should be noted that, instead of switching back to the source BWP, the first terminal device may report the second handover command to the network device, and the network device forwards the second handover command to the second terminal device.

It is easy to understand that, besides the second switching instruction, the communication between the first terminal device and the other terminal devices in the terminal device group may also be forwarded through the network device. Therefore, the BWP switching method two may further include the following steps:

during the process of switching the first terminal device from the source BWP to the target BWP, the first terminal device communicates with the second terminal device through the network device, such as forwarding multicast messages, to avoid interruption of the intra-group communication of the terminal devices.

Accordingly, the second terminal device performs the steps of:

and the second terminal device receives the second switching instruction sent by the first terminal device on the source BWP.

S405, the first end-point device switches from the source BWP to the target BWP again and communicates with the second end-point device on the target BWP.

Accordingly, the second terminal device performs the steps of:

the second terminal device switches from the source BWP to the target BWP and communicates with the second terminal device on the target BWP.

In a possible design method, the aforementioned first end-point device switches from the source BWP to the target BWP again, which may be implemented as:

the first terminal device switches from the source BWP to the target BWP again at a second switch time.

Optionally, the time deviation between the first switching time and the second switching time in S404 is smaller than the time deviation threshold, so as to reduce the communication interruption duration of the terminal device group during the switching from the source BWP to the target BWP, and further improve the reliability of the communication within the terminal device group. It will be readily appreciated that the time deviation threshold is typically set to a small value, such as 10 milliseconds, 1 slot, etc.

In this embodiment, the time deviation between the switching times of any two terminal devices in the terminal device group should be smaller than the time deviation threshold.

In the BWP handover method provided by the present application, after the first terminal device completes the measurement of the target BWP after the handover from the source BWP to the target BWP, if the first terminal device determines that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP, the switch-back to the source BWP sends the second handover instruction to the second terminal device, which instructs the second terminal device to handover from the source BWP to the target BWP to communicate with the second terminal device, so that the inter-terminal-device-group communication interruption duration caused by a large time deviation between different terminal devices in the terminal device group and the target BWP during the cell handover or entering or exiting the coverage area of the wireless network can be effectively reduced, thereby improving the reliability of inter-terminal-device-group communication during the handover of the BWP.

Fig. 5 is a flowchart of a third BWP handover method provided in this embodiment, which may be applied to a source network device in the wireless communication system shown in fig. 1 to reduce the interruption duration of direct communication in a terminal device group in any of the scenarios shown in fig. 2A to fig. 2C, so as to improve the reliability of direct communication in the terminal device group. The terminal equipment group comprises first terminal equipment and second terminal equipment.

It should be noted that, in the third BWP switching method shown in fig. 5, the BWP support capability of the terminal device group does not need to be defined. For example, all the terminal devices in the terminal device group may support the multi-BWP mode, or all the terminal devices may support only the single BWP mode, or some terminal devices may support the multi-BWP mode, and some terminal devices may support only the single BWP mode, which is not limited herein.

The third BWP handover method provided in the embodiment of the present application is described in detail below by taking a source network device as an example.

As shown in fig. 5, the third BWP switching method may include S501-S505:

s501, the source network device receives the measurement result of the target BWP reported by the first terminal device.

Specifically, the source network device receives a measurement result of the target BWP reported by the first terminal device through the Uu port. The measurement result of the target BWP may be referred to as S303 and S403, which is not described herein.

Optionally, the BWP switching method may further include: and the source network equipment sends the measurement task of the target BWP to the first terminal equipment through the Uu port.

S502, the source network device determines that the terminal device group needs to be switched from the source BWP to the target BWP according to the measurement result of the target BWP.

Specifically, if the source network device determines that the measurement result of the target BWP satisfies the BWP handover condition, the source network device determines that the terminal device group needs to be handed over from the source BWP to the target BWP. The BWP handover condition can be referred to as S303, which is not described herein again.

S503, the source network device sends a third switching instruction to the terminal device group.

Wherein the third switching instruction is used for instructing the terminal device group to switch from the source BWP to the target BWP.

Specifically, the source network device sends the third switching instruction to the terminal device group through the Uu port.

In one possible design method, the third handover command includes configuration information of the target BWP. Wherein, the configuration information of the target BWP may refer to S303, which is not described herein again.

Optionally, in a case that the terminal device group supports the multi BWP mode, the third switching instruction may further include: the start-up time of the target BWP corresponding to each terminal device in the terminal device group, and the disconnection time for disconnecting the direct communication on the source BWP. The start time and the off time may be referred to in the related descriptions in S305 and S306, respectively, and are not described herein again.

Optionally, in a case that the terminal device group supports only the single BWP mode, the third switching instruction may further include: a third switching time and a fourth switching time.

Wherein the third switching time is used for the first terminal device to switch from the source BWP to the target BWP again, the fourth switching time is used for the second terminal device to switch from the source BWP to the target BWP, and a time deviation between the third switching time and the fourth switching time is less than the time deviation threshold. The third switching time and the fourth switching time may refer to the description related to the first switching time and the second switching time in S405, which is not described herein again.

After receiving the third handover instruction, the first terminal device and the second terminal device may execute S504:

s504, switching to the target BWP according to the third switching instruction.

S505, communication is performed on the target BWP.

In the BWP switching method provided by the present application, the source network device may determine, according to the measurement result of the target BWP reported by the first terminal device, that the terminal device group needs to be switched from the source BWP to the target BWP, and issue the third switching instruction to each terminal device in the terminal device group, so that each terminal in the terminal device group switches from the source BWP to the target BWP according to the third switching instruction, and reestablish the intra-group direct communication of the terminal device group on the sidelink SL on the target BWP, which may avoid or effectively reduce the inter-group direct communication interruption duration of the terminal device group on the sidelink SL during the cell switching or entering or exiting the coverage area of the wireless network, thereby improving the reliability of the intra-group communication of the terminal device during the BWP switching.

The BWP switching method provided in the embodiment of the present application is described in detail above with reference to fig. 3 to 5. The communication device according to the embodiment of the present application is described in detail below with reference to fig. 6 to 11.

Fig. 6 is a communication apparatus according to an embodiment of the present application, configured to execute the function of a first terminal device in a terminal device group in the foregoing method embodiment. Wherein the terminal device group further includes a second terminal device, and the terminal device group supports a multi BWP mode.

As shown in fig. 6, the communication apparatus 600 includes: a first communication module 601, a second communication module 602, and a control module 603.

Wherein, the first communication module 601 is configured to communicate with the second terminal device on the source BWP.

A control module 603, configured to control the second communication module 602 to measure the target BWP while the first communication module 601 communicates with the second terminal device on the source BWP, and determine that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP.

The first communication module 601 is further configured to send a first handover instruction to the second terminal device on the source BWP. Wherein the first handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP.

A second communication module 602 for communicating with a second terminal device on the target BWP.

The control module is further configured to determine that the terminal device group needs to be handed over from the source BWP to the target BWP if the measurement result of the target BWP satisfies the BWP handover condition.

In one possible design, the control module 603 is further configured to control the first communication module 601 to stop communicating with the second terminal device on the source BWP after the first communication module 601 and the second communication module 602 communicate with the second terminal device on the target BWP and the source BWP, respectively.

In one possible design, as shown in fig. 7, the communication apparatus 600 may further include: a third communication module 604.

The third communication module 604 is configured to receive a measurement task of a target BWP sent by a source network device or a target network device.

Accordingly, the control module 603 is further configured to control the second communication module 602 to start the measurement task of the target BWP by itself if the third communication module 604 does not detect any wireless signal sent by the network device.

The communication device 600 may be a terminal device, or may be a chip disposed in the terminal device, which is not limited in this application.

Fig. 8 is another communication apparatus according to an embodiment of the present application, configured to execute the function of the first terminal device in the terminal device group in the foregoing method embodiment. Wherein the terminal device group further includes a second terminal device, and the terminal device group supports only the single BWP mode.

As shown in fig. 8, the communication apparatus 800 includes: a fourth communication module 801 and a control module 802.

Wherein, the fourth communication module 801 is configured to communicate with the second terminal device on the source BWP.

A control module 802, configured to control the fourth communication module 801 to switch from the source BWP to the target BWP, and measure the target BWP.

The control module 802 is further configured to determine that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP.

The control module 802 is further configured to control the fourth communication module 801 to switch back to the source BWP, and send a second switching instruction to the second terminal device on the source BWP. Wherein the second handover instruction is used to instruct the second terminal device to handover from the source BWP to the target BWP.

The control module 802 is further configured to control the fourth communication module 801 to switch from the source BWP to the target BWP again and communicate with the second terminal device on the target BWP.

In one possible design, the second handover instruction includes a first handover time, and the first handover time is a time when the second terminal device is handed over from the source BWP to the target BWP. Accordingly, the control module 802 is further configured to control the fourth communication module 801 to switch from the source BWP to the target BWP again at the second switching time. Wherein a time deviation between the first switching time and the second switching time is less than a time deviation threshold.

In one possible design, as shown in fig. 9, the communication device 800 further includes: a fifth communication module 803.

Wherein, the fifth communication module 803 is configured to communicate with the second terminal device through the network device during the process that the control module 802 controls the fourth communication module 801 to measure the target BWP, and to communicate with the second terminal device through the network device during the process that the control module 802 controls the fourth communication module 801 to switch from the source BWP to the target BWP.

Optionally, the fifth communication module 803 is further configured to receive a measurement task of the target BWP sent by the source network device or the target network device.

Optionally, the control module 802 is further configured to control the fourth communication module 801 to start the measurement task of the target BWP by itself if the fifth communication module 803 does not detect any wireless signal sent by the network device.

The control module 802 is further configured to determine that the terminal device group needs to be handed over from the source BWP to the target BWP if the measurement result of the target BWP satisfies the BWP handover condition.

Wherein the BWP switching condition includes at least one of:

the signal strength of the target BWP is above the BWP signal strength threshold; the signal quality of the target BWP is above the SL signal quality threshold;

the continuous duration of which the free resource occupancy on the source BWP is higher than the first occupancy threshold is greater than a first duration threshold;

The communication device 800 may be a terminal device, or may be a chip disposed in the terminal device, which is not limited in this application.

Fig. 10 is a further communication apparatus according to an embodiment of the present application, configured to perform the functions of the source network device in the foregoing method embodiments.

As shown in fig. 10, the communication apparatus 1000 includes: the communication apparatus 1000 includes: a sixth communication module 1001 and a control module 1002.

Wherein, the sixth communication module 1001 is configured to receive a measurement result of the target BWP sent by the first terminal device. The first terminal equipment belongs to a terminal equipment group, and the terminal equipment group further comprises second terminal equipment.

A control module 1002, configured to determine that the terminal device group needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP.

The sixth communication module 1001 is further configured to send a third switching instruction to the terminal device group. Wherein the third switching instruction is used for instructing the terminal device group to switch from the source BWP to the target BWP.

Optionally, the sixth communication module 1001 is further configured to send a measurement task of the target BWP to the first terminal device.

The control module 1002 is further configured to determine that the terminal device group needs to be handed over from the source BWP to the target BWP if the measurement result of the target BWP satisfies the BWP handover condition.

Wherein the BWP switching condition includes at least one of:

the signal strength of the target BWP is above the BWP signal strength threshold;

the signal quality of the target BWP is above the SL signal quality threshold;

The communication device 1000 may be a network device, or may be a chip disposed inside the network device, which is not limited in this application.

Further, the method according to the present application is also applicable to a unicast scenario, that is, a case where only the first terminal device and the second terminal device exist in the terminal device group. The detailed description of the method is omitted.

Fig. 11 is a schematic diagram of another communication apparatus according to an embodiment of the present application, which may be applied to the wireless communication system shown in fig. 1.

As shown in fig. 11, the communication apparatus 1100 includes: a processor 1101 and a transceiver 1102.

Wherein the processor 1101 is coupled with the transceiver 1102 and the memory 1103; a memory 1103 for storing a computer program.

A processor 1101 configured to execute the computer program stored in the memory 1103, so that the communication apparatus 1100 performs the function of the first terminal device in the BWP switching method shown in fig. 3 or fig. 4.

Illustratively, the processor 1101 is coupled to the transceiver 1102 and the memory 1103, and it may be that the processor 1101 is connectable to the transceiver 1102 and the memory 1103 by a bus 1104.

In one aspect, in one possible design, the communications apparatus 1100 includes one or more processors and one or more transceivers. The one or more processors are configured to support the communication apparatus 1100 to perform the corresponding functions of the terminal device in the BWP handover method described above. For example, it is determined that the group of terminal devices needs to be handed over from the source BWP to the target BWP, based on the measurement results of the target BWP. The transceiver is used to support the communications apparatus 1100 in communicating with other devices, implementing receiving and/or transmitting functions. For example, communicating with the second terminal device on the source BWP and/or on the target BWP, receiving a measurement task of the target BWP issued by the source network device or the target network device, and so on.

Optionally, the communication device 1100 may also include one or more memories coupled to the processor for storing program instructions and/or data necessary for the communication device 1100. The one or more memories may be integrated with the processor or may be separate from the processor, which is not limited in this application.

The communication device 1100 may be a smart phone, a vehicle-mounted terminal, or the like, and the transceiver may be a transceiving circuit. Optionally, the transceiver may also be an input/output circuit or interface.

The communication device 1100 may also be a communication chip. The transceiver may be an input/output circuit or interface of the communication chip.

In another possible design, the communications apparatus 1100 includes a transceiver, a processor, and a memory. The processor is configured to control the transceiver to transceive signals, the memory is configured to store a computer program, and the processor is configured to execute the computer program in the memory, so that the communication apparatus 1100 performs the function of the first terminal device in the BWP switching method as shown in fig. 3 or fig. 4.

In another aspect, in one possible design, the communications apparatus 1100 includes one or more processors, and one or more transceivers. The one or more processors are configured to support the communication apparatus 1100 to perform the functions performed by the source network device in the BWP handover method described above. For example, it is determined that the group of terminal devices needs to be handed over from the source BWP to the target BWP, based on the measurement results of the target BWP. The transceiver 1102 is configured to enable the communications apparatus 1100 to communicate with other devices to implement receiving and/or transmitting functions. For example, a measurement task of the target BWP is issued to the first terminal device, or a third switching instruction.

The communications apparatus 1100 can be a network device, such as a gNB, eNB, etc., and the transceiver can be transceiver circuitry. Optionally, the transceiver may also be an input/output circuit or interface.

The present application provides a communication system, which includes the aforementioned one or more network devices, and a plurality of terminal devices.

The present application provides a readable storage medium storing a program or instructions that, when executed on a computer, cause the computer to perform a function of a terminal device in the BWP switching method shown in fig. 3 or 4, or a function of a source network device in the BWP switching method shown in fig. 5.

The present application provides a computer program product comprising computer program code which, when run on a computer, causes the computer to function as a terminal device in the BWP switching method shown in fig. 3 or 4, or as a source network device in the BWP switching method shown in fig. 5.

It should be understood that the processor in the embodiments of the present application may be a Central Processing Unit (CPU), and the processor may also be other general purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

It will also be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of Random Access Memory (RAM) are available, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct bus RAM (DRRAM).

The above embodiments may be implemented in whole or in part by software, hardware (e.g., circuitry), firmware, or any combination thereof. When implemented in software, the above-described embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product comprises one or more computer instructions or computer programs. The procedures or functions according to the embodiments of the present application are wholly or partially generated when the computer instructions or the computer program are loaded or executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., infrared, wireless, microwave, etc.). 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, data center, etc. that contains one or more collections of available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium may be a solid state disk.

It should be understood that the term "and/or" herein is merely one type of association relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a alone, A and B together, and B alone, wherein A, B may be singular or plural. In addition, the "/" in this document generally indicates that the former and latter associated objects are in an "or" relationship, but may also indicate an "and/or" relationship, which may be understood with particular reference to the former and latter text.

In the present application, "at least one" means one or more, "a plurality" means two or more. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, may represent one of the following: a; b; c; a and b; a and c; b and c; a. b and c, wherein a, b and c can be single or multiple.

It should be understood that, in the various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

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

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A BWP handover method, adapted to a first terminal device of a group of terminal devices; the terminal equipment group also comprises second terminal equipment; the terminal equipment group supports a multi BWP mode;

the BWP switching method includes:

the first terminal device measuring a target BWP while communicating with the second terminal device over a source BWP;

the first terminal device determines that the terminal device group needs to be switched from the source BWP to the target BWP according to the measurement result of the target BWP;

the first terminal device sends a first switching instruction to the second terminal device on the source BWP; wherein the first handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP;

the first end-point device communicates with the second end-point device on the target BWP and on the source BWP.

2. The BWP handover method according to claim 1, wherein said first handover instruction comprises configuration information of said target BWP.

3. The BWP handover method according to claim 2, wherein said first handover command further comprises: the second terminal device starts a start time of the target BWP.

4. The BWP handover method according to claim 2 or 3, wherein said first handover command further comprises: a stop time for the second end-device to stop communicating with the first end-device on the source BWP.

5. The BWP switching method according to any one of claims 1-3, wherein said BWP switching method further comprises:

6. The BWP switching method according to claim 1, further comprising one of:

the first terminal device receives a measurement task of the target BWP sent by a source network device;

the first terminal device automatically starts the measurement task of the target BWP if the first terminal device does not detect a wireless signal sent by any network device;

and the first terminal device receives the measurement task of the target BWP sent by the target network device.

7. The BWP handover method according to claim 1, wherein said determining that the group of terminal devices needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP comprises:

if the measurement result of the target BWP meets a BWP switching condition, determining that the terminal device group needs to be switched from the source BWP to the target BWP; wherein the BWP handover condition includes at least one of:

the signal strength of the target BWP is above a BWP signal strength threshold;

the signal quality of the target BWP is above an SL signal quality threshold;

the continuous duration of which the free resource occupation ratio on the source BWP is higher than a first occupation ratio threshold value is larger than a first duration threshold value;

the continuous duration of which the free resource occupancy on the target BWP is lower than a second occupancy threshold is greater than a second duration threshold;

no traffic is present on the source BWP with a priority above a priority threshold.

8. A BWP handover method, adapted to a first terminal device of a group of terminal devices; the terminal equipment group also comprises second terminal equipment; the terminal equipment group only supports a single BWP mode;

the BWP switching method includes:

the first end-point device communicating with the second end-point device over a source BWP;

the first terminal device switches from the source BWP to a target BWP, and measures the target BWP;

the first terminal device switches back to the source BWP and sends a second switching instruction to the second terminal device on the source BWP; wherein the second handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP;

the first terminal device switches from the source BWP to the target BWP again and communicates with the second terminal device on the target BWP.

9. The BWP handover method according to claim 8, wherein said second handover instruction comprises a first handover time, said first handover time being a time for said second terminal device to handover from said source BWP to said target BWP;

the first terminal device again switching from the source BWP to the target BWP, comprising:

the first terminal device switches from the source BWP to the target BWP again at a second switch time; wherein a time deviation between the first switching time and the second switching time is less than a time deviation threshold.

10. The BWP handover method according to claim 8 or 9, wherein said second handover instruction further comprises configuration information of said target BWP.

11. The BWP switching method according to claim 8, wherein said BWP switching method further comprises at least one of:

the first terminal device communicates with the second terminal device through a network device in the process that the first terminal device measures the target BWP;

the first end device communicates with the second end device through a network device in the process of the first end device switching from the source BWP to the target BWP.

12. The BWP switching method according to claim 8, wherein said BWP switching method further comprises one of:

13. The BWP handover method according to claim 8, wherein said determining that the group of terminal devices needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP comprises:

the signal strength of the target BWP is above a BWP signal strength threshold;

the signal quality of the target BWP is above an SL signal quality threshold;

14. A BWP handover method, adapted for a source network device; the BWP switching method includes:

the source network device receives a measurement result of a target BWP sent by a first terminal device; the first terminal equipment belongs to a terminal equipment group, and the terminal equipment group further comprises second terminal equipment;

the source network device determines that a terminal device group needs to be switched from a source BWP to a target BWP according to the measurement result of the target BWP;

the source network device sends a third switching instruction to each terminal device in the terminal device group; wherein the third handover instruction is used to instruct the end-device group to handover from the source BWP to the target BWP, and the source BWP and the target BWP are both used to establish a sidelink.

15. The BWP handover method according to claim 14, wherein said third handover instruction comprises configuration information of said target BWP.

16. The BWP switching method of claim 15, wherein said third switching instruction further comprises: a third switching time and a fourth switching time; wherein the third switching time is used for the first terminal device to switch from the source BWP to the target BWP again, the fourth switching time is used for the second terminal device to switch from the source BWP to the target BWP, and a time deviation between the third switching time and the fourth switching time is less than a time deviation threshold.

17. The BWP switching method according to any of the preceding claims 14-16, wherein said BWP switching method further comprises:

and the source network device sends the measurement task of the target BWP to the first terminal device.

18. The BWP handover method according to claim 14, wherein said determining that the group of terminal devices needs to be handed over from the source BWP to the target BWP according to the measurement result of the target BWP comprises:

the signal strength of the target BWP is above a BWP signal strength threshold;

the signal quality of the target BWP is above an SL signal quality threshold;

19. A communication apparatus, adapted to a first terminal device of a group of terminal devices; the terminal equipment group also comprises second terminal equipment; the terminal equipment group supports a multi BWP mode;

the communication apparatus includes: the device comprises a first communication module, a second communication module and a control module; wherein,

the first communication module is configured to communicate with the second terminal device on a source BWP;

the control module is configured to control the second communication module to measure a target BWP while the first communication module communicates with the second terminal device over a source BWP;

the control module is further configured to determine, according to the measurement result of the target BWP, that the terminal device group needs to be handed over from the source BWP to the target BWP;

the first communication module is further configured to send a first handover instruction to the second terminal device on the source BWP; wherein the first handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP;

the second communication module is configured to communicate with the second terminal device on the target BWP.

20. The communications apparatus of claim 19, wherein the first handover instruction comprises configuration information of the target BWP.

21. The communications apparatus of claim 20, wherein the first handover instruction further comprises: the second terminal device starts a start time of the target BWP.

22. The communication device according to claim 20 or 21, wherein the first handover instruction further comprises: a stop time for the second end-device to stop communicating with the first end-device on the source BWP.

23. The communication device of claim 19,

the control module is further configured to control the first communication module to stop communicating with the second terminal device on the source BWP.

24. The communications device of claim 19, further comprising: a third communication module; wherein,

the third communication module is further configured to receive a measurement task of the target BWP sent by a source network device;

the control module is further configured to control the second communication module to start the measurement task of the target BWP by itself if the third communication module does not detect a wireless signal sent by any network device;

the third communication module is further configured to receive a measurement task of the target BWP sent by the target network device.

25. A communication apparatus, adapted to a first terminal device of a group of terminal devices; the terminal equipment group also comprises second terminal equipment; the terminal equipment group only supports a single BWP mode;

the communication apparatus includes: a fourth communication module and a control module; wherein,

the fourth communication module is configured to communicate with the second terminal device on a source BWP;

the control module is configured to control the fourth communication module to switch from the source BWP to a target BWP, and measure the target BWP;

the control module is further configured to control the fourth communication module to switch back to the source BWP, and send a second switching instruction to the second terminal device on the source BWP; wherein the second handover instruction is for instructing the second terminal device to handover from the source BWP to the target BWP;

the control module is further configured to control the fourth communication module to switch from the source BWP to the target BWP again, and communicate with the second terminal device on the target BWP.

26. The communications apparatus of claim 25, wherein the second handover instruction comprises a first handover time, wherein the first handover time is a time when the second terminal device is handed over from the source BWP to the target BWP;

the control module is further configured to control the fourth communication module to switch from the source BWP to the target BWP again at a second switching time; wherein a time deviation between the first switching time and the second switching time is less than a time deviation threshold.

27. The communication apparatus according to claim 25 or 26, wherein the second handover instruction further comprises configuration information of the target BWP.

28. The communications device of claim 25, further comprising: a fifth communication module: wherein,

the fifth communication module is configured to communicate with the second terminal device through a network device in a process that the control module controls the fourth communication module to measure the target BWP;

the fifth communication module is further configured to communicate with the second terminal device through a network device in a process that the control module controls the fourth communication module to switch from the source BWP to the target BWP.

29. The communication device of claim 28,

the fifth communication module is further configured to receive a measurement task of the target BWP sent by a source network device;

the control module is further configured to control the fourth communication module to start the measurement task of the target BWP by itself if the fifth communication module does not detect a wireless signal sent by any network device;

the fifth communication module is further configured to receive a measurement task of the target BWP sent by a target network device.

30. A communication apparatus, adapted to be used in a source network device; the communication apparatus includes: a sixth communication module and a control module; wherein,

the sixth communication module is configured to receive a measurement result of the target BWP sent by the first terminal device; the first terminal equipment belongs to a terminal equipment group, and the terminal equipment group further comprises second terminal equipment;

the control module is configured to determine, according to the measurement result of the target BWP, that the terminal device group needs to be handed over from the source BWP to the target BWP;

the sixth communication module is further configured to send a third switching instruction to each terminal device in the terminal device group; wherein the third handover instruction is used to instruct the end-device group to handover from the source BWP to the target BWP, and the source BWP and the target BWP are both used to establish a sidelink.

31. The communications apparatus of claim 30, wherein the third handover instruction comprises configuration information of the target BWP.

32. The communications apparatus of claim 31, wherein the third handover instruction further comprises: a third switching time and a fourth switching time; wherein the third switching time is used for the first terminal device to switch from the source BWP to the target BWP again, the fourth switching time is used for the second terminal device to switch from the source BWP to the target BWP, and a time deviation between the third switching time and the fourth switching time is less than a time deviation threshold.

33. The communication device according to any of claims 30-32,

the sixth communication module is further configured to send a measurement task of the target BWP to the first terminal device.

34. The communication device of claim 30,

the control module is further configured to determine that the terminal device group needs to be switched from the source BWP to the target BWP if the measurement result of the target BWP meets a BWP switching condition; wherein the BWP handover condition includes at least one of:

the signal strength of the target BWP is above a BWP signal strength threshold;

the signal quality of the target BWP is above an SL signal quality threshold;

35. A communications apparatus, comprising: a processor and a transceiver, the processor coupled with the transceiver and a memory;

the memory for storing a computer program;

the processor configured to execute the computer program stored in the memory to cause the communication device to perform the BWP handover method according to any one of claims 1-18.

36. A readable storage medium storing a program or instructions which, when run on a computer, causes the computer to perform the BWP switching method according to any one of claims 1-18.