A communication method and apparatus

Abstract

The application relates to the communication technical field, and discloses a communication method and device. The method comprises the following steps: a terminal device receives first information from a network device, the first information is used for indicating that multicast transmission of a first service is received on a first BWP; then, the terminal device switches an activated BWP from a second BWP to the first BWP according to the first information, and receives the multicast transmission of the service on the first BWP. By using the method, the network device indicates the terminal device to receive the multicast transmission of the first service on the first BWP through the first information, and then the terminal device switches to the first BWP according to the first information, so that the terminal device is switched to the multicast BWP to receive the multicast transmission of the service.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0002] In the fifth generation th In 5G (5G) communication systems, the maximum bandwidth of a carrier can reach 400MHz, but the maximum bandwidth supported by a terminal device may not reach this bandwidth. When a terminal device does not support the bandwidth capabilities of a carrier, network equipment cannot directly allocate frequency domain resources to the terminal device within the carrier bandwidth as in long-term evolution (LTE) systems. Instead, it must first configure one or more bandwidth parts (BWPs) within the carrier for the terminal device and then allocate resources to the terminal device within the BWPs.

[0003] Furthermore, in 5G communication systems, network devices can send multicast service data to terminal devices via unicast or multicast. For unicast transmission, network devices can use the terminal device's dedicated BWP to carry multicast service data; for multicast transmission, network devices must use a BWP shared by multiple terminal devices to carry multicast service data. Therefore, when a network device switches from unicast to multicast transmission, how terminal devices switch to the shared BWP to receive multicast service data requires further research. Summary of the Invention

[0004] The present application provides a communication method and apparatus for enabling a terminal device to switch to a multicast BWP to receive multicast transmission of a service.

[0005] In a first aspect, embodiments of the present application provide a communication method that can be applied to a terminal device or a chip within the terminal device. Taking the application of this method to a terminal device as an example, in this method, the terminal device receives first information from a network device, where the first information indicates that a multicast transmission of a first service is to be received on a first BWP (that is, the first BWP is a multicast BWP). Furthermore, the terminal device can switch a second BWP to the first BWP based on the first information and receive the multicast transmission of the first service on the first BWP.

[0006] Using this method, the network device instructs the terminal device to receive multicast transmission of the first service on the first BWP through the first information, and then the terminal device switches to the first BWP according to the first information, thereby enabling the terminal device to switch to the multicast BWP to receive multicast transmission of the service.

[0007] In a possible design, the first information is a first DCI scrambled by a G-RNTI associated with the first service; and the BWP corresponding to the G-RNTI is the first BWP.

[0008] In a possible design, the method further includes: receiving second information from the network device, where the second information is used to configure the correspondence between the G-RNTI and the first BWP.

[0009] In this way, by configuring the correspondence between the multicast BWP and the G-RNTI associated with the multicast service, and by implicitly indicating the terminal device to switch to the multicast BWP, the transmission resource can be effectively saved on the basis of implementing the switching of the terminal device to the multicast BWP.

[0010] In a possible design, the second information includes configuration information of the G-RNTI and the first BWP; the configuration information of the first BWP includes frequency domain starting position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain; or the configuration information of the first BWP includes an RIV corresponding to the first BWP, where the RIV is used to indicate frequency domain offset position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information is used to determine the frequency domain starting position information of the first BWP.

[0011] In a possible design, the second information further includes control resource set information and search space information, where the control resource set information and the search space information are used to indicate a time-frequency position corresponding to the first DCI.

[0012] In a possible design, the first information includes configuration information of the first BWP; the configuration information of the first BWP includes frequency domain starting position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain; or the configuration information of the first BWP includes a parameter resource indication value RIV corresponding to the first BWP, where the RIV is used to indicate frequency domain offset position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information of the first BWP is used to determine the frequency domain starting position information of the first BWP.

[0013] In this way, the network device does not need to pre-configure the first BWP for the terminal device. Instead, when the terminal device needs to switch to the first BWP, it can send the configuration information of the first BWP to the terminal device. This allows the terminal device to switch to the first BWP according to the configuration information of the first BWP and receive the multicast transmission of the service on the first BWP. This method, on the one hand, enables the terminal device to switch to the multicast BWP. On the other hand, it explicitly indicates the first BWP without setting the correspondence between the multicast BWP and the G-RNTI associated with the multicast service, which increases the flexibility of network device regulation.

[0014] In one possible design, the first information includes an identifier of a first BWP; the method further includes: receiving third information from a network device; wherein the third information is used to configure at least one BWP and an identifier of at least one BWP, and the at least one BWP includes the first BWP.

[0015] In this way, the network device can pre-configure the multicast BWP and the identifier of the multicast BWP for the terminal device, and then when the terminal device needs to switch to a multicast BWP (such as the first BWP), the identifier of the first BWP can be sent to the terminal device, so that the terminal device can switch to the first BWP according to the identifier of the first BWP and receive the multicast transmission of the service on the first BWP.

[0016] In one possible design, the first information includes an identifier of the group to which the first BWP belongs and an identifier of the first BWP within the group; the method also includes: receiving fourth information from a network device; wherein the fourth information is used to configure at least one BWP, an identifier of the group to which at least one BWP belongs, and an identifier of at least one BWP within the group to which at least one BWP belongs, and the at least one BWP includes the first BWP.

[0017] In one possible design, the identifier of the group to which the first BWP belongs includes the identifier of the type to which the first BWP belongs.

[0018] In one possible design, the first information is carried in the second DCI, and the second DCI is encrypted by the G-RNTI associated with the first service; or, the first information is carried in a control message of the MAC layer or a control message of the RLC layer or a control message of the PDCP layer.

[0019] In one possible design, the second BWP is switched to the first BWP according to the first information, including: when it is determined that the following first to third items are not met, the second BWP is switched to the first BWP according to the first information; wherein, the first item, when the first information is received, the unicast transmission of the second service is being received on the second BWP; wherein the priority of the first service is lower than or equal to the priority of the second service; or, the priority of the multicast transmission is lower than or equal to the priority of the unicast transmission; the second item, when the first information is received, the multicast transmission of the third service is being received on the second BWP, and the priority of the first service is lower than or equal to the priority of the third service; the third item, when the first information is received, the random access process is being performed on the second BWP.

[0020] In one possible design, the method further includes: switching the first BWP to a third BWP.

[0021] In one possible design, switching the first BWP to the third BWP includes: sending a request message to a network device, where the request message is used to request BWP switching; receiving a response message from the network device, and switching the first BWP to the third BWP according to the response message.

[0022] In one possible design, the request message includes an identifier of at least one candidate BWP; the request message is used to request to perform BWP switching, including: the request message is used to request to switch the first BWP to one of the at least one candidate BWP; the response message includes an identifier of a third BWP, and the third BWP is determined by at least one candidate BWP.

[0023] In one possible design, the at least one candidate BWP includes: a default BWP of the terminal device, and / or a second BWP.

[0024] In one possible design, the request message is a control message of the MAC layer, a control message of the RLC layer, a control message of the PDCP layer, or a message of the RRC layer.

[0025] In one possible design, switching the first BWP to the third BWP includes: determining that no multicast transmission of the first service is received on the first BWP within the first time period and no third DCI is detected, then switching the first BWP to the third BWP; or, if no third DCI is detected at M consecutive candidate time-frequency positions corresponding to the third DCI, then switching the first BWP to the third BWP; M is a positive integer; wherein the third DCI is used to schedule multicast transmission of the first service.

[0026] In one possible design, the first duration is determined based on indication information from the network device, wherein the indication information is carried in a system message or an RRC layer message or a fourth DCI, and the fourth DCI is encrypted by the G-RNTI of the first service.

[0027] In a second aspect, embodiments of the present application provide a communication method that can be applied to a network device or a chip within the network device. Taking the application of this method to a network device as an example, in this method, the network device sends first information to a terminal device, where the first information is used to instruct the terminal device to receive a multicast transmission of a first service on a first BWP; and the network device sends a multicast transmission of the first service on the first BWP.

[0028] In one possible design, the first information is a first DCI from a network device, and the first DCI is encrypted by a G-RNTI associated with a first service; the BWP corresponding to the G-RNTI is the first BWP.

[0029] In one possible design, the method further includes: sending second information to the terminal device, where the second information is used to configure the correspondence between the G-RNTI and the first BWP.

[0030] In one possible design, the second information includes the G-RNTI and configuration information of the first BWP; wherein, the configuration information of the first BWP includes the frequency domain starting position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain; or, the configuration information of the first BWP includes the RIV corresponding to the first BWP, the RIV is used to indicate the frequency domain offset position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information of the first BWP is used to determine the frequency domain starting position information of the first BWP.

[0031] In one possible design, the second information also includes control resource set information and search space information, and the time-frequency positions corresponding to the control resource set information and the search space information are used to carry the first DCI.

[0032] In one possible design, the first information includes configuration information of the first BWP; wherein, the configuration information of the first BWP includes the frequency domain starting position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain; or, the configuration information of the first BWP includes the RIV corresponding to the first BWP, the RIV is used to indicate the frequency domain offset position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information of the first BWP is used to determine the frequency domain starting position information of the first BWP.

[0033] In one possible design, the first information includes an identifier of a first BWP; the method also includes: the network device sends third information to the terminal device; wherein the third information is used to configure at least one BWP and an identifier of at least one BWP, and the at least one BWP includes the first BWP.

[0034] In one possible design, the first information includes an identifier of the group to which the first BWP belongs and an identifier of the first BWP within the group; the method also includes: the network device sends fourth information to the terminal device; wherein the fourth information is used to configure at least one BWP, an identifier of the group to which at least one BWP belongs, and an identifier of at least one BWP within the group to which at least one BWP belongs, and the at least one BWP includes the first BWP.

[0035] In one possible design, the identifier of the group to which the first BWP belongs includes the identifier of the type to which the first BWP belongs.

[0036] In one possible design, the first information is carried in the second DCI, and the second DCI is encrypted by the G-RNTI associated with the first service; or, the first information is carried in a control message of the MAC layer or a control message of the RLC layer or a control message of the PDCP layer.

[0037] In one possible design, the method further includes: receiving a request message from a terminal device, the request message being used to request execution of a BWP switch; and sending a response message to the terminal device according to the request message, the response message being used to instruct switching of the first BWP to a third BWP.

[0038] In one possible design, the request message includes an identifier of at least one candidate BWP; the request message is used to request to perform BWP switching, including: the request message is used to request to switch the first BWP to a BWP among at least one candidate BWP; the response message includes an identifier of a third BWP, and the third BWP is determined based on the at least one candidate BWP.

[0039] In one possible design, the at least one candidate BWP includes: a default BWP of the terminal device, and / or a second BWP.

[0040] In one possible design, the request message is a control message of the MAC layer, a control message of the RLC layer, a control message of the PDCP layer, or a message of the RRC layer.

[0041] In one possible design, the method also includes: sending indication information to the terminal device, the indication information is used to indicate the first duration; the indication information is carried in a system message or an RRC layer message or a fourth DCI, and the fourth DCI is encrypted by the G-RNTI of the first service.

[0042] It should be noted that the communication method provided in the above-mentioned second aspect corresponds to the communication method provided in the first aspect. The beneficial effects of the corresponding technical features can be found in the description of the first aspect and will not be repeated here.

[0043] In a third aspect, an embodiment of the present application provides a communication method, which can be applied to a terminal device, or can also be applied to a chip inside the terminal device. Taking the application of this method to a terminal device as an example, in this method, the terminal device receives first information from a network device, the first information being used to indicate receiving a multicast transmission of a first service on a first BWP; when it is determined that at least one of the following first to third items is met, the first information is ignored; wherein, in the first item, when the first information is received, unicast transmission of the second service is being performed on the second BWP; wherein the priority of the first service is lower than or equal to the priority of the second service; or, the priority of the multicast transmission is lower than or equal to the priority of the unicast transmission; in the second item, when the first information is received, multicast data of the third service is being transmitted on the second BWP, and the priority of the first service is lower than or equal to the priority of the third service; in the third item, when the first information is received, a random access process is being performed on the second BWP.

[0044] Using this method, when the terminal device receives the first information, it can first determine whether to perform a higher priority operation on the currently activated BWP. If so, the BWP switching operation can be temporarily not performed. Otherwise, the BWP switching operation can be performed, thereby effectively avoiding the interruption of the higher priority operation.

[0045] In one possible design, the method further includes: sending a notification message to the network device, where the notification message is used to indicate that the terminal device has ignored the first information.

[0046] In this way, after the terminal device ignores the first information, it sends a notification message to the network device so that the network device knows that the terminal device has ignored the first information, which facilitates the subsequent sending of the first service to the terminal device via unicast.

[0047] In one possible design, the method further includes receiving a unicast transmission of the first service on the second BWP.

[0048] Fourthly, embodiments of the present application provide a communication method that can be applied to a network device or a chip within the network device. Taking the application of this method to a network device as an example, in this method, the network device sends first information to a terminal device, where the first information is used to instruct the terminal device to receive a multicast transmission of a first service on a first BWP; and after the network device determines that the terminal device has ignored the first information, it sends a unicast transmission of the first service to the terminal device on a second BWP.

[0049] In a possible design, the network device determines that the terminal device ignores the first information, including: the network device receives notification information from the terminal device, and determines, according to the notification information, that the terminal device ignores the first information.

[0050] It should be noted that the communication method provided in the fourth aspect corresponds to the communication method provided in the third aspect, and the beneficial effects of the corresponding technical features can be referred to the description of the third aspect, which will not be repeated.

[0051] In the fifth aspect, the present application provides a communication apparatus, which can be a terminal device or a chip arranged in the terminal device. The communication apparatus has the functions of the first aspect or the third aspect, for example, the communication apparatus includes modules or units or means corresponding to the steps of the first aspect or the third aspect. The functions or units or means can be implemented by software or hardware, or by executing corresponding software by hardware.

[0052] In a possible design, the communication apparatus includes a processing unit and a communication unit, where the communication unit can be configured to transceive signals to implement communication between the communication apparatus and other apparatuses, for example, the communication unit is configured to receive configuration information from a network device; and the processing unit can be configured to perform some internal operations of the communication apparatus.

[0053] Based on this design, in an embodiment, the communication unit is configured to receive first information from a network device, where the first information is used to indicate multicast transmission of a first service on a first BWP; the processing unit is configured to switch a second BWP to the first BWP according to the first information; and the communication unit is further configured to receive the multicast transmission of the first service on the first BWP.

[0054] In a possible implementation manner of this embodiment, the first information is a first DCI, the first DCI is scrambled by a group radio G-RNTI associated with the first service, and the BWP corresponding to the G-RNTI is the first BWP.

[0055] In a possible implementation manner of this embodiment, the communication unit is further configured to receive second information from the network device, where the second information is used to configure a correspondence between the G-RNTI and the first BWP.

[0056] In a possible implementation of the embodiment, the first information includes configuration information of the first BWP; and the configuration information of the first BWP includes frequency domain starting position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain; or the configuration information of the first BWP includes a parameter resource indication value RIV corresponding to the first BWP, the RIV being used to indicate frequency domain offset position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information of the first BWP being used to determine the frequency domain starting position information of the first BWP.

[0057] In a possible implementation of the embodiment, the first information includes an identifier of the first BWP; and the communication unit is further configured to receive third information from the network device, the third information being used to configure at least one BWP and an identifier of the at least one BWP, the at least one BWP including the first BWP.

[0058] In a possible implementation of the embodiment, the first information includes an identifier of a group to which the first BWP belongs and an identifier of the first BWP in the group; and the communication unit is further configured to receive fourth information from the network device, the fourth information being used to configure at least one BWP, an identifier of a group to which the at least one BWP belongs, and an identifier of the at least one BWP in the group to which the at least one BWP belongs, the at least one BWP including the first BWP.

[0059] In a possible implementation of the embodiment, the first information is carried in a second DCI scrambled by a G-RNTI associated with the first service; or the first information is carried in a control message of a MAC layer or a control message of an RLC layer or a control message of a PDCP layer.

[0060] In a possible implementation of the embodiment, the processing unit is specifically configured to, when it is determined that the following first item to third item is not met, switch the second BWP to the first BWP according to the first information: the first item, when the first information is received, a unicast transmission of a second service is being received on the second BWP; and a priority of the first service is lower than or equal to a priority of the second service; or a priority of the multicast transmission is lower than or equal to a priority of the unicast transmission; the second item, when the first information is received, a multicast transmission of a third service is being received on the second BWP, and a priority of the first service is lower than or equal to a priority of the third service; and the third item, when the first information is received, a random access procedure is being performed on the second BWP.

[0061] In a possible implementation of this embodiment, the communication unit is further configured to send a request message to the network device, the request message being used to request execution of BWP switching; and receive a response message from the network device, and switch the first BWP to a third BWP according to the response message.

[0062] In a possible implementation of this embodiment, the request message includes an identifier of at least one candidate BWP; the request message is used to request execution of BWP switching, including: the request message is used to request switching of the first BWP to one of the at least one candidate BWP; the response message includes an identifier of a third BWP, and the third BWP is determined based on the at least one candidate BWP.

[0063] In a possible implementation of this embodiment, the communication unit is specifically used to determine that if the multicast transmission of the first service is not received on the first BWP within the first time period and the third DCI is not detected, then send a request message to the network device; or, if the third DCI is not detected at M consecutive candidate time-frequency positions corresponding to the third DCI, then send a request message to the network device; M is a positive integer; wherein the third DCI is used to schedule the multicast transmission of the first service.

[0064] In a possible implementation of this embodiment, the processing unit is specifically used to determine that if the multicast transmission of the first service is not received on the first BWP within the first time period and the third DCI is not detected, the first BWP is switched to the third BWP; or, if the third DCI is not detected at M consecutive candidate time-frequency positions corresponding to the third DCI, the first BWP is switched to the third BWP; M is a positive integer; wherein the third DCI is used to schedule the multicast transmission of the first service.

[0065] In another possible design, the communication device includes a processor and may also include a transceiver, wherein the transceiver is used to send and receive signals, and the processor executes program instructions to complete the method in any possible design or implementation of the first aspect or the third aspect above. The communication device may also include one or more memories, and the memory is used to couple with the processor. The one or more memories may be integrated with the processor or may be set separately from the processor, which is not limited in this application. The memory may store the necessary computer programs or instructions for implementing the functions involved in the first aspect or the third aspect above. The processor may execute the computer program or instructions stored in the memory, and when the computer program or instructions are executed, the communication device implements the method in any possible design or implementation of the first aspect or the third aspect above.

[0066] In yet another possible implementation of the embodiment, the communication apparatus includes a processor and a memory, and the memory can store computer programs or instructions necessary for implementing the functions related to the first aspect or the third aspect. The processor can execute the computer programs or instructions stored in the memory, and when the computer programs or instructions are executed, the communication apparatus can implement the method in any possible design or implementation manner of the first aspect or the third aspect.

[0067] In yet another possible implementation of the embodiment, the communication apparatus includes at least one processor and an interface circuit, and the at least one processor is configured to communicate with other apparatuses through the interface circuit and implement the method in any possible design or implementation manner of the first aspect or the third aspect.

[0068] In a sixth aspect, the present application provides a communication apparatus, which can be a network device or a chip arranged in the network device. The communication apparatus is configured to implement the functions related to the second aspect or the fourth aspect, for example, the communication apparatus includes modules or units or means corresponding to the steps related to the second aspect or the fourth aspect, and the functions or units or means can be implemented by software or hardware, or by executing corresponding software by hardware.

[0069] In a possible design, the communication apparatus includes a processing unit and a communication unit, and the communication unit can be configured to transceive signals to implement communication between the communication apparatus and other apparatuses, for example, the communication unit is configured to send system information to a terminal device; and the processing unit is configured to perform some internal operations of the communication apparatus.

[0070] Based on this design, in an embodiment, the communication unit is configured to send, to a terminal device, first information used to indicate multicast transmission of first service on a first BWP; and send, on the first BWP, the multicast transmission of the first service.

[0071] In a possible implementation of the embodiment, the first information is a first DCI scrambled by a G-RNTI associated with the first service; and the BWP corresponding to the G-RNTI is the first BWP.

[0072] In a possible implementation of the embodiment, the communication unit is further configured to send, to the terminal device, second information used to configure a correspondence between the G-RNTI and the first BWP.

[0073] In a possible implementation of this embodiment, the first information includes configuration information of the first BWP; wherein, the configuration information of the first BWP includes frequency domain starting position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain; or, the configuration information of the first BWP includes a parameter resource indication value RIV corresponding to the first BWP, and the RIV is used to indicate the frequency domain offset position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information is used to determine the frequency domain starting position information.

[0074] In a possible implementation of this embodiment, the first information includes an identifier of a first BWP; the communication unit is further used to send third information to the terminal device; wherein the third information is used to configure at least one BWP and an identifier of the at least one BWP, and the at least one BWP includes the first BWP.

[0075] In a possible implementation of this embodiment, the first information includes an identifier of the group to which the first BWP belongs and an identifier of the first BWP within the group; the communication unit is also used to send fourth information to the terminal device; wherein the fourth information is used to configure the at least one BWP, the identifier of the group to which the at least one BWP belongs, and the identifier of the at least one BWP within the group to which the at least one BWP belongs, and the at least one BWP includes the first BWP.

[0076] In a possible implementation of this embodiment, the first information is carried in the second DCI, and the second DCI is encrypted by the G-RNTI associated with the first service; or, the first information is carried in a control message of the MAC layer or a control message of the RLC layer or a control message of the PDCP layer.

[0077] In a possible implementation of this embodiment, the communication unit is further used to receive a request message from the terminal device, wherein the request message is used to request to perform BWP switching; and send a response message to the terminal device according to the request message, wherein the response message is used to instruct to switch the first BWP to the third BWP.

[0078] In a possible implementation of this embodiment, the request message includes an identifier of at least one candidate BWP; the request message is used to request execution of BWP switching, including: the request message is used to request switching the first BWP to one of the at least one candidate BWP; the response message includes an identifier of a third BWP, and the third BWP is determined based on the at least one candidate BWP.

[0079] In another possible design, the communication device includes a processor and may also include a transceiver, the transceiver is used to send and receive signals, and the processor executes program instructions to complete the method in any possible design or implementation of the second aspect or the fourth aspect above. The communication device may also include one or more memories, and the memory is used to couple with the processor. The one or more memories may be integrated with the processor or may be set separately from the processor, which is not limited in this application. The memory may store the necessary computer programs or instructions for implementing the functions involved in the second or fourth aspect above. The processor may execute the computer program or instructions stored in the memory, and when the computer program or instructions are executed, the communication device implements the method in any possible design or implementation of the second or fourth aspect above.

[0080] In another possible design, the communication device includes a processor and a memory, and the memory may store the necessary computer programs or instructions for implementing the functions of the second or fourth aspects. The processor may execute the computer program or instructions stored in the memory. When the computer program or instructions are executed, the communication device implements the method in any possible design or implementation of the second or fourth aspects.

[0081] In another possible design, the communication device includes at least one processor and an interface circuit, wherein at least one processor is used to communicate with other devices through the interface circuit and execute the method in any possible design or implementation of the second aspect or the fourth aspect above.

[0082] In the seventh aspect, the present application provides a communication system, which includes a terminal device, which is used to execute the method in any possible design of the first aspect or the third aspect mentioned above; the communication system may also include a network device, which is used to execute the method in any possible design of the second aspect or the fourth aspect mentioned above.

[0083] In an eighth aspect, the present application provides a computer-readable storage medium, in which computer-readable instructions are stored. When a computer reads and executes the computer-readable instructions, the computer executes the method in any possible design of the first to fourth aspects above.

[0084] In a ninth aspect, the present application provides a computer program product, which, when read and executed by a computer, enables the computer to execute the method in any possible design of the first to fourth aspects above.

[0085] In a tenth aspect, the present application provides a chip, comprising a processor, wherein the processor is coupled to a memory and is configured to read and execute a software program stored in the memory to implement a method in any possible design of the first to fourth aspects above.

[0086] These and other aspects of the present application will become more readily apparent from the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] Figure 1 A schematic diagram of a network architecture applicable to an embodiment of the present application;

[0088] Figure 2a This is another network architecture diagram applicable to the embodiments of the present application;

[0089] Figure 2b A schematic diagram of information transmission between layers provided in an embodiment of the present application;

[0090] Figure 3 This is another network architecture diagram applicable to the embodiments of the present application;

[0091] Figure 4a 、 Figure 4b and Figure 4c A schematic diagram of the configuration of the BWP in the carrier bandwidth provided in an embodiment of the present application;

[0092] Figure 5 This is a flow chart corresponding to the communication method provided in Example 1 of the present application;

[0093] Figure 6 A schematic diagram showing the meaning of various parameters of the search space provided in the embodiment of the present application;

[0094] Figure 7 This is a flow chart corresponding to the communication method provided in Example 2 of the present application;

[0095] Figure 8 This is a flow chart corresponding to the communication method provided in Example 3 of the present application;

[0096] Figure 9 This is a flow chart corresponding to the communication method provided in Example 4 of the present application;

[0097] Figure 10a An example diagram of a MAC sub-PDU provided in an embodiment of the present application;

[0098] Figure 10b An example diagram of an RLC PDU or PDCP PDU provided in an embodiment of the present application;

[0099] Figure 10cAnother example diagram of a MAC sub-PDU provided in an embodiment of the present application;

[0100] Figure 10d This is another example diagram of an RLC PDU or PDCP PDU provided in an embodiment of the present application;

[0101] Figure 11 A possible exemplary block diagram of the apparatus involved in the embodiments of the present application;

[0102] Figure 12 A schematic diagram of the structure of a terminal device provided in an embodiment of the present application;

[0103] Figure 13 A schematic diagram of the structure of a network device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0104] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application.

[0105] First, some of the terms used in the embodiments of the present application are explained to facilitate understanding by those skilled in the art.

[0106] (1) Terminal device: It can be a wireless terminal device that can receive network device scheduling and instruction information. The wireless terminal device can be a device that provides voice and / or data connectivity to users, or a handheld device with wireless connection function, or other processing equipment connected to a wireless modem. The terminal device can communicate with one or more core networks or the Internet via a radio access network (RAN). The terminal device can be a mobile terminal device, such as a mobile phone (or "cellular" phone, mobile phone), a computer and a data card. For example, it can be a portable, pocket-sized, handheld, computer-built-in or vehicle-mounted mobile device that exchanges voice and / or data with the radio access network. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), tablet computers (Pads), computers with wireless transceiver functions, and other devices. A wireless terminal device may also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a mobile station (MS), a remote station (remotestation), an access point (AP), a remote terminal, an access terminal, a user terminal, a user agent, a subscriber station (SS), a customer premises equipment (CPE), a terminal, a user equipment (UE), a mobile terminal (MT), etc. A terminal device may also be a wearable device or a next-generation communication system, for example, a terminal device in a 5G communication system or a terminal device in a future-evolved public land mobile network (PLMN).

[0107] (2) Network device: can be a device in a wireless network, for example, the network device can be a radio access network (RAN) node (or device) that accesses a terminal device to a wireless network, which can also be referred to as a base station. At present, some examples of RAN devices are: a new generation base station (gNodeB) in a 5G communication system, a transmission reception point (TRP), an evolved Node B (eNB), a radio network controller (RNC), a Node B (NB), a base station controller (BSC), a base transceiver station (BTS), a home base station (for example, a home evolved Node B, or a home Node B, HNB), a baseband unit (BBU), or a wireless fidelity (Wi-Fi) access point (AP), etc. In addition, in one network structure, the network device can include a centralized unit (CU) node, or a distributed unit (DU) node, or a RAN device including a CU node and a DU node. Furthermore, in other possible cases, the network device can be other apparatuses that provide wireless communication functions for terminal devices. Embodiments of the present application do not limit the specific technology and specific device form adopted by the network device. For the convenience of description, the apparatus that provides wireless communication functions for terminal devices is referred to as a network device in the embodiments of the present application.

[0108] (3) The terms "system" and "network" in the embodiments of the present application can be used interchangeably. "At least one" means one or more, and "more" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, "at least one of A, B and C" includes A, B, C, AB, AC, BC or ABC. In addition, unless otherwise specified, the ordinal numbers such as "first" and "second" mentioned in the embodiments of the present application are used to distinguish multiple objects, and are not used to limit the order, timing, priority or importance of multiple objects.

[0109] Figure 1 This is a schematic diagram of a network architecture applicable to the embodiment of this application. Figure 1 As shown, the terminal device 130 can access a wireless network to obtain services from an external network (such as the Internet) through the wireless network, or communicate with other devices through the wireless network, such as other terminal devices. The wireless network includes a RAN and a core network (CN). The RAN is used to connect terminal devices (such as terminal device 1301 or terminal device 1302) to the wireless network, and the CN is used to manage the terminal devices and provide a gateway for communicating with the external network.

[0110] The RAN may include one or more RAN devices, such as RAN device 1101 and RAN device 1102.

[0111] The CN may include one or more CN devices, such as CN device 120. Figure 1 When the network architecture shown is applicable to a 5G communication system, the CN device 120 may be an access and mobility management function (AMF) entity or a user plane function (UPF) entity, etc.

[0112] It should be understood that Figure 1 The number of devices in the communication system shown is for illustration only, and the embodiments of the present application are not limited thereto. In actual applications, the communication system may further include more terminal devices, more RAN devices, and other devices.

[0113] Figure 2a This is another network architecture diagram applicable to the embodiment of this application. Figure 2a As shown, the network architecture includes CN equipment, RAN equipment, and terminal equipment. The RAN equipment includes a baseband device and a radio frequency device, wherein the baseband device can be implemented by one node or multiple nodes, and the radio frequency device can be implemented independently from the baseband device or integrated into the baseband device, or some functions can be integrated independently and some functions can be integrated into the baseband device. For example, in an LTE communication system, the RAN equipment includes a baseband device and a radio frequency device, wherein the radio frequency device can be arranged remotely from the baseband device, for example, a remote radio unit (RRU) is a remote radio unit arranged relative to the BBU.

[0114] The communication between RAN equipment and terminal equipment follows a certain protocol layer structure. For example, the control plane protocol layer structure may include the functions of the radio resource control (RRC) layer, the packet data convergence protocol (PDCP) layer, the radio link control (RLC) layer, the media access control (MAC) layer and the physical layer; the user plane protocol layer structure may include the functions of the PDCP layer, the RLC layer, the MAC layer and the physical layer; in one possible implementation, the service data adaptation protocol (SDAP) layer may also be included above the PDCP layer. Taking the information transmission between the network equipment and the terminal equipment as an example, the information transmission needs to pass through the control plane protocol layer, such as the PDCP layer, the RLC layer, the MAC layer and the physical layer, among which the PDCP layer, the RLC layer, the MAC layer and the physical layer can also be collectively referred to as the access layer. Taking the downlink transmission as an example, see Figure 2b The figure shows the schematic diagram of the transmission of control information between layers. Figure 2bThe downward arrow in the figure indicates information sending, and the upward arrow indicates information receiving. After the PDCP layer obtains information from the upper layer, it transmits the information to the RLC layer and the MAC layer, and then the MAC layer transmits it to the physical layer, and then transmits it wirelessly through the physical layer. Information is encapsulated accordingly in each layer. The information received by a layer from the upper layer of the layer is considered to be the service data unit (SDU) of the layer. After layer encapsulation, it becomes a PDU and is then passed to the next layer. For example, the information received by the PDCP layer from the upper layer is called PDCP SDU, and the information sent by the PDCP layer to the lower layer is called PDCP PDU; the information received by the RLC layer from the upper layer is called RLC SDU, and the information sent by the RLC layer to the lower layer is called RLC PDU; the information received by the MAC layer from the upper layer is called MAC SDU, and the information sent by the MAC layer to the lower layer is called MAC PDU. In the protocol, the connection between layers is mostly corresponded in the form of channels. The RLC layer and the MAC layer correspond via a logical channel (LCH), while the MAC layer and the physical layer correspond via a transport channel. Below the physical layer is the physical channel, which is used to correspond to the physical layer at the other end.

[0115] The RAN device can implement the functions of the protocol layers such as RRC, PDCP, RLC and MAC by one node, or can implement the functions of these protocol layers by multiple nodes. For example, in an evolutionary structure, the RAN device can include CU and DU, and multiple DUs can be centrally controlled by one CU. Figure 2a As shown, the CU and DU can be divided according to the protocol layers of the wireless network, for example, the functions of the PDCP layer and above are set in the CU, and the functions of the protocol layers below the PDCP, such as the RLC layer and the MAC layer, are set in the DU. This division of the protocol layers is only an example, and it can also be divided in other protocol layers, for example, division in the RLC layer, setting the functions of the RLC layer and above protocol layers in the CU, and the functions of the protocol layers below the RLC layer in the DU; or, division in a certain protocol layer, for example, setting part of the functions of the RLC layer and the functions of the protocol layers above the RLC layer in the CU, and setting the remaining functions of the RLC layer and the functions of the protocol layers below the RLC layer in the DU. In addition, it can also be divided in other ways, such as division by latency, setting the functions whose processing time needs to meet the latency requirements in the DU, and the functions that do not need to meet the latency requirements in the CU. In addition, the radio frequency device can be independently integrated and not placed in the DU, or it can be integrated in the DU, or part of it can be remotely integrated in the DU, and there is no limitation here.

[0116] Figure 3This is another network architecture diagram applicable to the embodiment of this application. Figure 2a The network architecture shown, Figure 3 The control plane (CP) and user plane (UP) of the CU can also be separated and implemented into different entities, namely the control plane (CP) CU entity (i.e., CU-CP entity) and the user plane (UP) CU entity (i.e., CU-UP entity).

[0117] In the above network architecture, the signaling generated by the CU can be sent to the terminal device through the DU, or the signaling generated by the terminal device can be sent to the CU through the DU. The DU can directly encapsulate the signaling through the protocol layer and transparently transmit it to the terminal device or CU without parsing it. In the following embodiments, if the transmission of such signaling between the DU and the terminal device is involved, then the sending or receiving of the signaling by the DU includes this scenario. For example, the signaling of the RRC or PDCP layer will eventually be processed as the signaling of the PHY layer and sent to the terminal device, or converted from the received signaling of the PHY layer. Under this architecture, the signaling of the RRC or PDCP layer can also be considered to be sent by the DU, or sent by the DU and the radio frequency device.

[0118] above Figure 1 、 Figure 2a or Figure 3 The network architecture shown can be applicable to communication systems of various radio access technologies (RATs), for example, a 4G (or LTE) communication system, a 5G (or new radio, NR) communication system, a transition system between an LTE communication system and a 5G communication system, which can also be called a 4.5G communication system, and of course, a future communication system. The network architecture and service scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. It is known to those skilled in the art that with the evolution of the communication network architecture and the emergence of new service scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0119] The apparatuses in the following embodiments of the present application may be located in a terminal device or a network device according to the functions they implement. When the above CU-DU structure is adopted, the network device may be a CU, a DU, or a RAN device including a CU and a DU.

[0120] The following first explains the relevant technical features involved in the embodiments of the present application. It should be noted that these explanations are intended to make the embodiments of the present application easier to understand and should not be regarded as limiting the scope of protection claimed by the present application.

[0121] 1. BWP

[0122] With the above Figure 1 、 Figure 2a or Figure 3 The illustrated network architecture is applicable to a 5G communication system, for example. In a 5G communication system, to adapt the bandwidth capabilities of a terminal device, a BWP can be configured for the terminal device within the bandwidth supported by a carrier (referred to as the carrier bandwidth, which can be 10 MHz, 15 MHz, 20 MHz, 50 MHz, 100 MHz, or 400 MHz, etc.). Multiple BWPs can be configured for a carrier; for example, four BWPs can be configured for a carrier. BWP is sometimes also referred to as a carrier bandwidth part, or other names. This application does not limit the name; for ease of description, the name BWP is used as an example. For example, a BWP includes K (K>0) subcarriers; or, a BWP is the frequency domain resource where N non-overlapping resource blocks (RBs) are located, and the subcarrier spacing of the RB can be 15KHz, 30KHz, 60KHz, 120KHz, 240KHz, 480KHz or other values ​​(such as 7.5KHz or 1.25KHz); or, a BWP is the frequency domain resource where m (m>0) non-overlapping resource block groups (RBGs) are located, for example, an RBG includes P (P>0) consecutive RBs, and the subcarrier spacing (SCS) of the RB can be 15KHz, 30KHz, 60KHz, 120KHz, 240KHz, 480KHz or other values, such as an integer multiple of 2.

[0123] (1) Example of BWP configuration in carrier bandwidth

[0124] like Figure 4a-4c As shown, the configuration of three BWPs in the carrier bandwidth provided in the embodiment of the present application is shown. Figure 4aIn the case of configuring a BWP in the carrier bandwidth, the network device can first allocate a BWP within the terminal bandwidth capability to the terminal device, and of course can further allocate part or all of the resources in the BWP to the terminal device for communication. The network device can configure different BWP situations for the terminal device according to the actual scenario. For example, in order to save the power consumption of the terminal device, the network device can allocate a BWP to the terminal device according to the business volume of the terminal device. When the terminal device has no business data transmission or only a small amount of business data transmission, a smaller BWP can be allocated to the terminal device for receiving control information and a small amount of data information, such as Figure 4b When the terminal device has a large amount of business data to transmit, a larger BWP can be allocated to the terminal device, such as Figure 4b As another example, since the 5G communication system can support multiple service types and communication scenarios, different parameters can be configured for different service types and communication scenarios. The network device can allocate corresponding BWP to the terminal device according to the different service types of the terminal device, such as Figure 4c As shown, a BWP can correspond to a service type. In order to meet the service requirements of the service type, the BWP can be configured with frame structure parameters (numerology) that can meet the service requirements. Figure 4b It can be seen that different BWPs can occupy partially overlapping frequency domain resources. Figure 4c It is known that different BWPs may occupy completely different frequency domain resources and use different numerologies. In the embodiment of the present application, the numerologies corresponding to different BWPs may be the same or different, and the present application does not impose any limitation. It is understood that, Figure 4a-4c In the example, only one or two BWPs are configured in one carrier. In actual applications, multiple BWPs can be configured in a carrier, which is not limited in the embodiments of the present application.

[0125] (2) Classification of BWP

[0126] Exemplarily, BWPs can be roughly divided into two categories: 1) Initial BWP, which is the BWP used by the terminal device during the initial access phase; 2) Dedicated BWP, which is the BWP configured by the network device for the terminal device after the terminal device enters the connected state. Typically, for a terminal device, the network device can configure up to four dedicated BWPs and the identifiers of each dedicated BWP through RRC messages; at the same time, the terminal device can only have one dedicated BWP in the active state, that is, the terminal device can only use one BWP. The first activated BWP (First Active BWP) can be indicated by RRC signaling. Furthermore, the network device can configure a default BWP for the terminal device through an RRC reconfiguration message. The default BWP can be one of the dedicated BWPs. If the network device does not configure a default BWP, the terminal device can consider the initial BWP to be the default BWP.

[0127] (3) Switching of BWP

[0128] After a network device configures one or more dedicated BWPs for a terminal device, one or more dedicated BWPs are in an inactive state. The network device may send an indication to the terminal device to activate one of the dedicated BWPs; this indication may be carried in an RRC message. Accordingly, the terminal device receives the indication and activates the dedicated BWP, allowing it to communicate with the network device over the dedicated BWP. Subsequently, the terminal device may switch between multiple BWPs, including an initial BWP and dedicated BWPs. There may be various scenarios in which the terminal device switches between the initial BWP and dedicated BWPs.

[0129] For example, in scenario 1, if a terminal device determines that it needs to initiate a random access procedure, the currently active BWP is not configured with random access resources, but another BWP is configured with random access resources. The terminal device can then switch to the other BWP to initiate the random access procedure on the other BWP. This other BWP can be the terminal device's initial BWP or another dedicated BWP. In this scenario, the terminal device can trigger the BWP switch.

[0130] For example, in scenario 2, if the network device determines that the load of the BWP currently activated by the terminal device is large or the resources of the BWP currently activated by the terminal device are insufficient, it can instruct the terminal device to switch to another BWP, which can be another dedicated BWP of the terminal device. For example, the network device sends downlink control information (DCI) to the terminal device. The DCI is used to instruct the terminal device to switch to another BWP. The DCI is scrambled by the cell-radio network temporary identifier (C-RNTI), and the DCI includes the identifier of the other BWP. Accordingly, after the terminal device detects the DCI according to the C-RNTI, it can switch to the other BWP and communicate with the network device on the other BWP.

[0131] 2. Multicast Transmission Technology

[0132] Multicast transmission technology is a transmission technology in which a sender sends data and multiple receivers receive the data; for example, a network device sends data and multiple terminal devices receive the data. Among them, one possible multicast transmission technology is single cell point to multipoint (SC-PTM) technology. In SC-PTM technology, a physical downlink share channel (PDSCH) can be used to transmit data of multicast services. Different from the PDSCH that carries unicast services, the PDSCH that carries multicast services can be called multicast PDSCH. The network device can pre-configure the association between the multicast service and the group-radio network temporary identity (G-RNTI), and each multicast service can be associated with one G-RNTI.

[0133] For multicast transmission, the network device can send downlink control information (DCI) carried on the physical downlink control channel (PDCCH) to multiple terminal devices interested in the multicast service. The DCI is used to schedule the multicast PDSCH that carries the multicast service. The DCI can be scrambled by the G-RNTI associated with the multicast service. Accordingly, after multiple terminal devices detect the DCI based on the G-RNTI associated with the multicast service, they can receive the multicast PDSCH based on the scheduling information included in the DCI.

[0134] For unicast transmission, the network device can send DCI to the terminal device. The DCI is used to schedule the unicast PDSCH that carries a certain service (the service can be a unicast service or a multicast service). The DCI can be scrambled by C-RNTI; accordingly, after the terminal device detects the DCI according to the C-RNTI, it can receive the unicast PDSCH according to the scheduling information included in the DCI.

[0135] 3. Multicast BWP

[0136] As described above, BWPs in current 5G communication systems include an initial BWP and a dedicated BWP for terminal devices. Terminal devices can communicate with network devices over dedicated BWPs, for example, receiving data sent by network devices via unicast. However, given the increasing maturity of vertical industries, an increasing number of services require multicast transmission technology, such as vehicle-to-everything (V2X) and public safety. Therefore, one possible approach to achieving multicast transmission of services in 5G communication systems is to introduce multicast BWPs.

[0137] The multicast BWP can be used for multicast transmission of services. For example, the multicast BWP can be a BWP shared by multiple terminal devices, so that the multiple terminal devices can receive data sent by the network device in a multicast manner on the multicast BWP.

[0138] The embodiments of this application will investigate the implementation of multicast BWP. For example, after the introduction of multicast BWP, a terminal device can switch between an initial BWP, a dedicated BWP, and a multicast BWP. The specific implementation of terminal device switching between the initial BWP and the dedicated BWP can be found in the previous description. However, further research is required to determine how a terminal device switches to a multicast BWP. Based on this, the embodiments of this application provide a communication method for enabling a terminal device to switch to a multicast BWP to receive multicast transmissions of a service.

[0139] The communication method provided in the embodiments of the present application is described in detail below in conjunction with Examples 1 to 5.

[0140] In the following introduction, this method is applied to Figure 1The system architecture shown is taken as an example. In addition, the method can be executed by two communication devices, which are, for example, a first communication device and a second communication device, wherein the first communication device can be a network device or a communication device that can support the network device to implement the functions required by the method, and of course it can also be other communication devices, such as a chip or a chip system. The second communication device can be a terminal device or a communication device that can support the terminal device to implement the functions required by the method, and of course it can also be other communication devices, such as a chip or a chip system. For ease of introduction, in the following, the method is taken as an example of being executed by a network device and a terminal device, that is, the first communication device is a network device and the second communication device is a terminal device. If this embodiment is applied to Figure 1 The system architecture shown below is used to execute Figure 5 、 Figure 7 、 Figure 8 or Figure 9 The network device of the embodiment shown may be Figure 1 The RAN device 110 shown is used to perform the following Figure 5 、 Figure 7 、 Figure 8 or Figure 9 The terminal device of the embodiment shown can be Figure 1 The terminal device 130 is shown.

[0141] Example 1

[0142] In embodiment one, a correspondence between a multicast BWP and a G-RNTI associated with a multicast service can be set. When a network device determines that a multicast transmission of a first service needs to be sent, a DCI (referred to as DCI-1 for ease of description) can be sent to multiple terminal devices, and the DCI-1 is encrypted by the first G-RNTI associated with the first service; wherein the first service is a multicast service, and the multiple terminal devices refer to terminal devices that are interested in the first service. Accordingly, after the multiple terminal devices detect the DCI-1 according to the first G-RNTI, they can determine that the first G-RNTI corresponds to the first BWP based on the correspondence between the multicast BWP and the G-RNTI, and then switch to the first BWP to receive the multicast transmission of the first service. The following will describe a possible implementation process by taking the interaction between a network device and a terminal device that is interested in the first service as an example.

[0143] Figure 5 This is a flow chart corresponding to the communication method provided in Example 1 of this application. Figure 5 As shown, including:

[0144] In step 501, a network device sends configuration information 1 and configuration information 2 to a terminal device. Configuration information 1 can be used to configure one or more multicast BWPs, and configuration information 2 can be used to configure one or more dedicated BWPs for the terminal device. Accordingly, the terminal device can receive configuration information 1 and configuration information 2.

[0145] Here, configuration information 1 and configuration information 2 are described in detail.

[0146] 1. Configuration Information 1

[0147] Configuration information 1 can be used to configure one or more multicast BWPs (such as BWP1 and BWP2). Furthermore, configuration information 1 can also configure the correspondence between one or more multicast BWPs and one or more G-RNTIs, where a multicast BWP and a G-RNTI can have a one-to-one correspondence. It should be noted that since each multicast service is associated with a G-RNTI, the correspondence between a multicast BWP and a G-RNTI can also be replaced by a correspondence between a multicast BWP and a multicast service.

[0148] In one example, configuration information 1 may include configuration information of multiple multicast BWPs and G-RNTIs corresponding to the multiple multicast BWPs, and optionally, physical layer configuration information corresponding to the multiple multicast BWPs. Table 1 shows an example of information included in configuration information 1.

[0149] Table 1: Example of information included in configuration information 1

[0150] Multicast BWP configuration information G-RNTI corresponding to multicast BWP Physical layer configuration information BWP1 configuration information G-RNTI1 Physical layer configuration information corresponding to BWP1 BWP2 configuration information G-RNTI2 Physical layer configuration information corresponding to BWP2

[0151] In another example, configuration information 1 may include configuration information for multiple multicast services (e.g., multicast service 1 and multicast service 2). Taking multicast service 1 as an example, the configuration information for multicast service 1 may include G-RNTI1 associated with multicast service 1, configuration information for BWP1 corresponding to G-RNTI1, and optionally, physical layer configuration information corresponding to BWP1.

[0152] Table 2 shows another example of the information included in the configuration information 1.

[0153] Table 2: Example of information included in configuration information 1

[0154] Multicast services Multicast service configuration information Multicast Service 1 G-RNTI1, BWP1 configuration information, and BWP1 corresponding physical layer configuration information Multicast Service 2 G-RNTI2, BWP2 configuration information, and BWP2 corresponding physical layer configuration information

[0155] Exemplarily, the configuration information of the multicast service may also include other possible information, such as DRX parameters, which are not specifically limited.

[0156] Taking BWP1 as an example, the configuration information of the BWP involved in the above example and the physical layer configuration information corresponding to the BWP are explained.

[0157] (1) BWP1 configuration information

[0158] For example, the configuration information of BWP1 may include the frequency domain starting position information of BWP1 and the bandwidth information occupied by BWP1 in the frequency domain; and then, after receiving the configuration information 1, the terminal device may determine the specific position of BWP1 in the carrier bandwidth based on the frequency domain starting position information of BWP1 and the bandwidth information occupied by BWP1 in the frequency domain. The frequency domain starting position information of BWP1 may refer to the absolute position information of BWP1 relative to CRB0; the bandwidth information occupied by BWP1 in the frequency domain may refer to the number of RBs or physical resource blocks (PRBs) continuously occupied by BWP1 in the frequency domain.

[0159] For example, the configuration information of BWP1 may include the frequency domain offset position information of BWP1 and the bandwidth information occupied by BWP1 in the frequency domain (locationAndBandwidth). The value of locationAndBandwidth can also be understood as the parameter resource indication value (RIV). RIV is used to indicate the frequency domain offset position information of BWP1 and the bandwidth information occupied by BWP1 in the frequency domain. After the terminal device receives the configuration information 1, it can obtain the frequency domain offset position information of BWP1 and the bandwidth information occupied by BWP1 in the frequency domain according to the RIV corresponding to BWP1, and determine the frequency domain starting position information of BWP1 according to the frequency domain offset position information and offset information of BWP1, and then determine the specific position of BWP1 in the carrier bandwidth according to the frequency domain starting position information of BWP1 and the bandwidth information occupied by BWP1 in the frequency domain. Among them, the frequency domain offset position information of BWP1 is an intermediate quantity used to determine the frequency domain starting position information of BWP1; the offset information (offsetToCarrier) may refer to the frequency domain offset between the frequency domain reference point (PointA) and the minimum / lowest available subcarrier on the carrier. The maximum value of the frequency domain offset corresponds to 275*8-1. For details, see 3GPP TS 38.211, Section 4.4.2. Exemplarily, the offset information may be included in configuration information 1, or may be sent by the network device to the terminal device through other possible messages, which is not specifically limited.

[0160] For example, if the RIV of BWP1 is 13037, and the calculation method is preset (see the prior art for the specific calculation method), the frequency domain offset position of BWP1 is 112, and the bandwidth occupied by BWP1 in the frequency domain is 48 PRBs. If the offset information is = 13, the frequency domain starting position of this BWP1 is (13 + 112) * PRB = 125 PRB.

[0161] Exemplarily, the configuration information of BWP1 may also include other possible information, such as the subcarrier spacing of BWP1, the length indication of the cyclic prefix, etc., which are not specifically limited. Among them, the length of the cyclic prefix indicates whether to use an extended cyclic prefix on BWP1. For example, if the configuration information of BWP1 does not include or does not set this indication, the terminal device can use a normal cyclic prefix. Conversely, if the configuration information of BWP1 includes this indication, the terminal device can use an extended cyclic prefix. The normal cyclic prefix applies to all subcarrier spacings and time slot formats, and the extended cyclic prefix applies to 60kHz subcarrier spacing (see 3GPP TS 38.211, Section 4.2).

[0162] (2) Physical layer configuration information corresponding to BWP1

[0163] The physical layer configuration information corresponding to BWP1 may include a search space and a control resource set (CORESET), and there may be an association relationship between the search space and the CORESET. The search space and the CORESET associated with the search space may be used to indicate multiple candidate time-frequency positions corresponding to DCI, and the multiple candidate time-frequency positions are located in BWP1. The network device may send DCI to the terminal device at some of the multiple candidate time-frequency positions of BWP1; accordingly, after receiving the physical layer configuration information, the terminal device may monitor DCI at the multiple candidate time-frequency positions of BWP1.

[0164] It should be noted that: (1) The DCI here can be DCI scrambled by G-RNTI1, G-RNTI2 or C-RNTI or other possible RNTI. (2) Exemplarily, the search space and CORESET can be configured separately for multicast transmission. Specifically, multiple search spaces can be configured on BWP1, and the uses of multiple search spaces can be indicated during configuration, for example: for paging (pagingSearchSpace), for random access (ra-SearchSpace), and for receiving SIB1 (searchSpaceSIB1). For example, in an embodiment of the present application, when configuring the search space, it can be indicated that the use of the search space is for multicast (multicastSearchSpace). It can be understood that the CORESETs associated with the search spaces for different purposes can be the same or different.

[0165] The control resource set determines the frequency domain resources for transmitting DCI, that is, DCI can be transmitted on the frequency domain resources corresponding to the control resource set, and the frequency domain resources corresponding to the control resource set can include multiple RBs. The search space determines the time domain resources for transmitting DCI, and the search space can be configured with some time domain information, such as: period (i.e., the time interval for detecting the search space, which can be in time slots); time slot offset (i.e., the time slot offset between the start of the detection period and the actual detection of the search space, and the time slot offset is less than the value of the detection period); first duration (configured by the duration parameter, i.e., the time for continuous detection of the search space, which can include multiple time slots, and the number of time slots included is less than the value of the detection period); time domain starting position (i.e., the time domain starting position corresponding to the control resource set associated with the search space within each time slot).

[0166] For easier understanding, the meaning of each parameter is introduced with specific examples. Figure 6 As shown in the figure, the search space period is 10 time slots, the time slot offset is 3 time slots, the first duration is 2 time slots, the time domain starting position is symbol 0 and symbol 7 within a time slot, and the second duration of the control resource set associated with the search space is 2 symbols. In this example, the terminal device can detect DCI on symbols 0, 1, 7, and 8 in time slots 3 and 4 within the detection period of every 10 time slots.

[0167] In addition, the physical layer configuration information corresponding to the BWP1 can further include physical layer parameters required for receiving the PDSCH on the BWP1. The physical layer parameters required for receiving the PDSCH on the BWP1 can include a timing relationship between the PDCCH and the PDSCH. The network device can pre-configure the timing relationship between the PDCCH and the PDSCH through an RRC message. When the resource is dynamically scheduled using the DCI, the network device can indicate which timing relationship is used in the DCI. For example, when the value in the DCI is 0, the first timing relationship in the timing relationship table configured by the RRC message is used; when the value in the DCI is 1, the second timing relationship in the timing relationship table is used; and so on.

[0168] The configuration of each timing relationship can include at least one of the following: (1) a time slot offset K0 between the DCI and the PDSCH scheduled by the DCI (see section 5.1.2.1 in TS 38.214), when the offset corresponding field does not exist, the terminal device can take the value 0 by default; (2) a PDSCH mapping type indication (mappingType), see section 5.3 in TS 38.214; (3) an index of a valid combination of a starting symbol and a length (joint coding) (startSymbolAndLength), which can be used as a starting and length indicator (SLIV). The network device configures this field so that the resource allocation does not cross the time slot boundary (see section 5.1.2.1 in TS 38.214).

[0169] II. Configuration information 2

[0170] The configuration information 2 can be used to configure one or more dedicated BWPs (such as the BWP3 and the BWP4) for the terminal device, and further be used to configure the identification of the one or more dedicated BWPs. The identification of the dedicated BWP can be information used to identify the dedicated BWP, such as the number of the dedicated BWP.

[0171] As shown in Table 3, an example of the information included in the configuration information 2 is shown.

[0172] Table 3: Example of information included in the configuration information 2

[0173] Dedicated BWP logo Dedicated BWP configuration information Physical layer configuration information BWP3 logo BWP3 configuration information Physical layer configuration information corresponding to BWP3 BWP4 logo BWP4 configuration information Physical layer configuration information corresponding to BWP4

[0174] Exemplarily, the configuration information and the physical layer configuration information of the dedicated BWP can refer to the related description of the configuration information 1 in the foregoing, which will not be described herein.

[0175] III. Ways in which the network device sends the configuration information 1 and the configuration information 2

[0176] Exemplarily, the network device may send configuration information 1 and configuration information 2 through the same message; for example, the network device may send configuration information 1 and configuration information 2 through an RRC message. Alternatively, the network device may send configuration information 1 and configuration information 2 through different messages; for example, the network device may send configuration information 1 through RRC message 1 and send configuration information 2 through RRC message 2; for another example, the network device may send configuration information 1 through a system message and send configuration information 2 through an RRC message.

[0177] It should be noted that the above step 501 can also be replaced by step 501': the network device sends configuration information 1 and configuration information 2 to the terminal device; wherein, configuration information 1 is used to configure the correspondence between the multicast BWP and the G-RNTI, and configuration information 2 is used to configure multiple BWPs, and can also be used to configure the identifiers of multiple BWPs. The multiple BWPs may include one or more dedicated BWPs and one or more multicast BWPs.

[0178] For example, the multiple BWPs include BWP1, BWP2, BWP3, and BWP4, where BWP1 and BWP2 are multicast BWPs and BWP3 and BWP4 are dedicated BWPs. It is understood that the example of configuring four BWPs using configuration information 2 is used here. In a specific implementation, configuration information 2 can configure more than four BWPs, and the specific number is not limited in this embodiment of the application.

[0179] Regarding configuration information 2, in an example, configuration information 2 may include identifiers of multiple BWPs, configuration information of multiple BWPs, and physical layer configuration information corresponding to the multiple BWPs, as shown in Table 4.

[0180] Table 4: Example of information included in configuration information 2

[0181] BWP logo BWP configuration information Physical layer configuration information BWP1 logo BWP1 configuration information Physical layer configuration information corresponding to BWP1 BWP2 logo BWP2 configuration information Physical layer configuration information corresponding to BWP2 BWP3 logo BWP3 configuration information Physical layer configuration information corresponding to BWP3 BWP4 logo BWP4 configuration information Physical layer configuration information corresponding to BWP4

[0182] Regarding configuration information 1, in one example, configuration information 1 may include identifiers of multiple multicast BWPs and G-RNTIs corresponding to the multiple multicast BWPs. Table 5 is an example of information included in configuration information 1.

[0183] Table 5: Example of information included in configuration information 1

[0184] Multicast BWP identifier G-RNTI corresponding to multicast BWP BWP1 logo G-RNTI1 BWP2 logo G-RNTI2

[0185] For the configuration information 1, in yet another example, the configuration information 1 can comprise configuration information of a plurality of multicast services (such as multicast service 1 and multicast service 2). Taking the multicast service 1 as an example, the configuration information of the multicast service 1 can comprise the G-RNTI1 associated with the multicast service 1, and the identifier of the BWP1 corresponding to the G-RNTI1. As shown in Table 6, an example of the information comprised in the configuration information 1.

[0186] Table 6: Example of information comprised in the configuration information 1

[0187] Multicast services Multicast service configuration information Multicast Service 1 G-RNTI1, BWP1 identification, and physical layer configuration information corresponding to BWP1 Multicast Service 2 G-RNTI2, BWP2 identifier, and physical layer configuration information corresponding to BWP2

[0188] The step 501' described herein is different from the step 501 in that, in the step 501', one or more multicast BWPs can be additionally configured in the manner of configuring the dedicated BWP in the prior art, and the correspondence between the multicast BWP and the G-RNTI can be configured by the identifier of the multicast BWP in the configuration information 2 (i.e., the configuration information of the multicast BWP can not need to be included in the configuration information 2). Except for the difference, the two can be referred to each other. In this way, the one or more multicast BWPs are configured in the manner of the prior art, and the modification to the prior art is small, thereby making the present application have strong applicability. And since the configuration information 2 comprises less information, the resource overhead of the configuration information 2 can be effectively saved.

[0189] In step 502, the terminal device activates the second BWP and communicates with the network device on the second BWP.

[0190] In one example, the second BWP can be the initial BWP or the dedicated BWP. In this case, the second BWP can be the BWP activated by the network device for the terminal device through the RRC message, or can also be the BWP activated by the network device for the terminal device through the DCI scrambled by the C-RNTI, or can also be the BWP activated through other manners, which is not limited in particular.

[0191] In yet another example, the second BWP can be one of the plurality of multicast BWPs, such as the BWP1 or the BWP2.

[0192] In step 503, after the network device determines that the multicast transmission of the first service needs to be sent, the network device sends the first information to the terminal device, the first information being used to indicate the first BWP, and the first BWP being used for the multicast transmission of the first service; correspondingly, the terminal device receives the first information.

[0193] The first information is used to indicate the first BWP, and may include: the first information is used to instruct the terminal device to switch to the first BWP; or the first information is used to instruct the terminal device to receive multicast transmission of the first service on the first BWP. The first BWP may be one of multiple multicast BWPs, for example, the first BWP is BWP1 or BWP2.

[0194] For example, the first information may be DCI-1. If the terminal device detects DCI-1 through G-RNTI1, it means that DCI-1 is encrypted using G-RNTI1, and the terminal device can determine, based on the above configuration information 1, that it needs to switch to BWP1 to receive the multicast transmission of multicast service 1; if the terminal device detects DCI-1 through G-RNTI2, it means that DCI-1 is encrypted using G-RNTI2, and the terminal device can determine, based on the above configuration information 1, that it needs to switch to BWP2 to receive the multicast transmission of multicast service 2.

[0195] Step 504: The terminal device switches the activated BWP from the second BWP to the first BWP according to the first information.

[0196] Here, the terminal device switches the activated BWP from the second BWP to the first BWP, which can be understood as the terminal device deactivating the currently activated BWP (i.e., the second BWP) and activating the first BWP; or, it can also be understood as the terminal device switching from working on the second BWP to working on the first BWP.

[0197] Step 505: The network device sends a multicast transmission of the first service to the terminal device on the first BWP (ie, sends data of the first service to the terminal device via multicast). Accordingly, the terminal device receives the multicast transmission of the first service on the first BWP.

[0198] Here, the terminal device can determine whether the currently activated BWP (i.e., the second BWP) matches the first BWP. If they match (for example, the second BWP and the first BWP are the same BWP), the terminal device can receive the multicast transmission of the first service on the second BWP; if they do not match (for example, the second BWP and the first BWP are different BWPs), the terminal device can switch the activated BWP from the second BWP to the first BWP according to the first information, and receive the multicast transmission of the first service on the first BWP.

[0199] In an embodiment of the present application, after receiving the multicast transmission of the first service on the first BWP, the terminal device may also send feedback information of the multicast transmission to the network device on the first BWP. The feedback information is used to indicate whether the data of the first service is successfully transmitted, so that the network device can determine the data transmission status based on the feedback information. The feedback information may be hybrid automatic repeat request (HARQ) feedback information, such as a HARQ acknowledgment (ACK) or a negative acknowledgement (NACK).

[0200] By adopting the solution in the above-mentioned embodiment 1, by setting the correspondence between the multicast BWP and the G-RNTI associated with the multicast service, the network device can instruct the terminal device to switch to the multicast BWP through an implicit indication method. On the one hand, the terminal device can switch to the multicast BWP in a timely and effective manner to receive multicast transmission. On the other hand, the use of an implicit indication method can effectively save transmission resources.

[0201] Example 2

[0202] In the second embodiment, when the network device determines that it needs to send a multicast transmission of the first service, it can send DCI (referred to as DCI-2 for ease of description) to multiple terminal devices; DCI-2 can be scrambled by the first G-RNTI associated with the first service, or it can also be scrambled by C-RNTI; DCI-2 includes the configuration information of the first BWP, or the PDSCH scheduled by DCI-2 includes the configuration information of the first BWP; wherein, the first service is a multicast service, and the multiple terminal devices refer to terminal devices interested in the first service. Accordingly, after receiving DCI-2 or the PDSCH scheduled by DCI-2, the multiple terminal devices can obtain the configuration information of the first BWP, and then switch to the first BWP to receive the multicast transmission of the first service. The following will describe a possible implementation process by taking the interaction between a network device and a terminal device interested in the first service as an example.

[0203] Figure 7 This is a flow chart corresponding to the communication method provided in Example 2 of this application, such as Figure 7 Shown, including:

[0204] Step 701: The network device sends configuration information to the terminal device. The configuration information can be used to configure one or more dedicated BWPs for the terminal device. Correspondingly, the terminal device can receive the configuration information.

[0205] Here, the configuration information can also be used to configure the identity of one or more dedicated BWPs, which can be seen from the description of the configuration information 2 in Embodiment I, and will not be repeated here.

[0206] In step 702, the terminal device activates the second BWP and communicates with the network device on the second BWP.

[0207] Here, the second BWP can be an initial BWP, a dedicated BWP, or a multicast BWP.

[0208] In step 703, the network device sends first information to the terminal device, the first information being used to indicate receiving multicast transmission of the first service on the first BWP; correspondingly, the terminal device receives the first information.

[0209] Here, the first information can include configuration information of the first BWP; further, the first information can also include physical layer configuration information corresponding to the first BWP.

[0210] In one example, the first information can be carried in DCI-2, which can be scrambled by C-RNTI or G-RNTI associated with the first service. In this case, after detecting DCI-2 according to C-RNTI or G-RNTI associated with the first service, the terminal device can obtain the first information from DCI-2.

[0211] In another example, the first information can be carried in a PDSCH scheduled by DCI-2, which can be scrambled by C-RNTI or G-RNTI associated with the first service. In this case, after detecting DCI-2 according to C-RNTI or G-RNTI associated with the first service, the terminal device can receive the PDSCH according to the scheduling information in DCI-2, and then obtain the first information from the PDSCH. Here, according to the protocol layer architecture shown in the above Figure 2b As can be seen from the protocol layer architecture shown in the above

[0212] In step 704, the terminal device switches the activated BWP from the second BWP to the first BWP according to the first information.

[0213] In step 705, the network device sends multicast transmission of the first service to the terminal device on the first BWP, and correspondingly, the terminal device receives the multicast transmission of the first service on the first BWP.

[0214] Here, the terminal device can determine whether the currently activated BWP (i.e., the second BWP) matches the first BWP. If they match (for example, the second BWP and the first BWP are the same BWP), the terminal device can receive the multicast transmission of the first service on the second BWP; if they do not match (for example, the second BWP and the first BWP are different BWPs), the terminal device can switch the activated BWP from the second BWP to the first BWP according to the first information, and receive the multicast transmission of the first service on the first BWP.

[0215] By adopting the solution in the second embodiment above, the network device does not need to pre-configure a multicast BWP for the terminal device. Instead, when the terminal device needs to switch to the multicast BWP, the network device can send the multicast BWP configuration information to the terminal device via DCI or DCI-scheduled PDSCH, so that the terminal device can switch to the multicast BWP according to the multicast BWP configuration information and receive the multicast transmission of the service on the multicast BWP. This approach, on the one hand, enables the terminal device to switch to the multicast BWP, and on the other hand, it explicitly indicates the first BWP without setting the correspondence between the multicast BWP and the G-RNTI associated with the multicast service, thereby increasing the flexibility of network device regulation.

[0216] Example 3

[0217] In the third embodiment, when the network device determines that a multicast transmission of the first service needs to be sent, it can send a DCI (referred to as DCI-3 for ease of description) to multiple terminal devices; the DCI-3 can be scrambled by the first G-RNTI associated with the first service, or it can also be scrambled by the C-RNTI; the DCI-3 includes the identifier of the first BWP or the identifier of the group to which the first BWP belongs and the identifier of the first BWP within the group, or the PDSCH scheduled by the DCI-3 includes the identifier of the first BWP or the identifier of the group to which the first BWP belongs and the identifier of the first BWP within the group; wherein, the first service is a multicast service, and the multiple terminal devices refer to terminal devices interested in the first service. Accordingly, after receiving the DCI-3 or the PDSCH scheduled by the DCI-3, the multiple terminal devices can obtain the identifier of the first BWP or the identifier of the group to which the first BWP belongs and the identifier of the first BWP within the group, and then switch to the first BWP to receive the multicast transmission of the first service. The following will describe a possible implementation process by taking the interaction between the network device and a terminal device interested in the first service as an example.

[0218] Figure 8 This is a flow chart corresponding to the communication method provided in Example 3 of this application, such as Figure 8 Shown, including:

[0219] Step 801: The network device sends configuration information to the terminal device. The configuration information can be used to configure at least one BWP, for example, the at least one BWP includes BWP1, BWP2, BWP3, and BWP4.

[0220] Here, at least one BWP may include a multicast BWP, for example, BWP1, BWP2, BWP3 and BWP4 may all be multicast BWPs; or, at least one BWP may include a multicast BWP and a dedicated BWP, for example, BWP1 and BWP2 are multicast BWPs, and BWP3 and BWP4 are dedicated BWPs.

[0221] Exemplarily, a network device may send configuration information to a terminal device in various ways. For example, the network device may send an RRC message to the terminal device, the RRC message including the configuration information. In this case, the at least one BWP may include a multicast BWP, or the at least one BWP may include a multicast BWP and a dedicated BWP. For another example, the network device may send a system message to the terminal device, the system message including the configuration information. In this case, the at least one BWP may include a multicast BWP.

[0222] In an example, the configuration information may also be used to configure an identifier of at least one BWP, that is, the configuration information may also be used to configure an identifier of each BWP in BWP1, BWP2, BWP3, and BWP4.

[0223] In another example, the configuration information can also be used to configure the identifier of the group to which at least one BWP belongs and the identifier of at least one BWP within the group to which the at least one BWP belongs. For example, the at least one BWP can be grouped according to the type to which the at least one BWP belongs, and the identifier of the group to which the at least one BWP belongs can be the identifier of the type to which the at least one BWP belongs. The type to which the at least one BWP belongs can include a dedicated BWP and a multicast BWP. For example, the identifier of the group to which BWP1 and BWP2 belong is the identifier of a multicast BWP, and the identifier of BWP1 within the group is numbered 1, and the identifier of BWP2 within the group is numbered 2; the identifier of the group to which BWP3 and BWP4 belong is the identifier of a dedicated BWP, and the identifier of BWP3 within the group is numbered 1, and the identifier of BWP4 within the group is numbered 2. Alternatively, the type to which the at least one BWP belongs can include a BWP corresponding to a URLLC service and a BWP corresponding to a multicast service; or, the type to which the at least one BWP belongs can also include other possible types, which are not specifically limited.

[0224] Step 802: The terminal device activates the second BWP and communicates with the network device on the second BWP.

[0225] Here, the second BWP may be an initial BWP, a dedicated BWP, or a multicast BWP.

[0226] Step 803: The network device sends first information to the terminal device, where the first information is used to instruct the terminal device to receive multicast transmission of the first service on the first BWP. Accordingly, the terminal device receives the first information.

[0227] Here, the first information may include an identifier of the first BWP, or the first information may include an identifier of a group to which the first BWP belongs and an identifier of the first BWP in the group.

[0228] In one example, the first information may be carried in DCI-3, and DCI-3 may be scrambled by C-RNTI or G-RNTI associated with the first service. In this case, after the terminal device detects DCI-3 based on C-RNTI or G-RNTI associated with the first service, it may obtain the first information from DCI-3.

[0229] In another example, the first information can be carried in the PDSCH scheduled by DCI-3, and the DCI-3 can be scrambled by the C-RNTI or the G-RNTI associated with the first service. In this case, after the terminal device detects the DCI-3 according to the C-RNTI or the G-RNTI associated with the first service, it can receive the PDSCH according to the scheduling information in the DCI-3, and then obtain the first information from the PDSCH. The first information can be carried in a control message of the MAC layer, a control message of the RLC layer, or a control message of the PDCP layer.

[0230] Step 804: The terminal device switches the activated BWP from the second BWP to the first BWP according to the first information.

[0231] Step 805 : The network device sends a multicast transmission of the first service to the terminal device on the first BWP (ie, sends data of the first service to the terminal device via multicast). Accordingly, the terminal device receives the multicast transmission of the first service on the first BWP.

[0232] Here, the terminal device can determine whether the currently activated BWP (i.e., the second BWP) matches the first BWP. If they match (for example, the second BWP and the first BWP are the same BWP), the terminal device can receive the multicast transmission of the first service on the second BWP; if they do not match (for example, the second BWP and the first BWP are different BWPs), the terminal device can switch the activated BWP from the second BWP to the first BWP according to the first information, and receive the multicast transmission of the first service on the first BWP.

[0233] By adopting the solution in the third embodiment above, the network device can pre-configure the multicast BWP and the identifier of the multicast BWP (or the identifier of the group to which the multicast BWP belongs and the identifier of the multicast BWP within the group) for the terminal device. Then, when the terminal device needs to switch to the multicast BWP, the identifier of the multicast BWP is sent to the terminal device via DCI or PDSCH scheduled by DCI, so that the terminal device can switch to the multicast BWP according to the identifier of the multicast BWP and receive the multicast transmission of the service on the multicast BWP. By adopting this method, on the one hand, the terminal device is switched to the multicast BWP, and on the other hand, the first BWP is indicated in an explicit manner without setting the correspondence between the multicast BWP and the G-RNTI associated with the multicast service, thereby increasing the flexibility of network device regulation. Moreover, since the identifier of the multicast BWP usually only occupies a small amount of transmission resources, it can effectively save transmission resources.

[0234] In the above embodiments 1 to 3, the implementation of switching a terminal device to a multicast BWP is described, that is, the terminal device can receive a first message from a network device and switch the second BWP to the first BWP based on the first message. However, considering that the terminal device may execute a higher priority operation on the second BWP when receiving the first message, switching the second BWP to the first BWP in this case may cause the higher priority operation to be interrupted.

[0235] Based on this, a communication method is also provided in an embodiment of the present application. In this communication method, when the terminal device receives the switching information, it can determine whether the preset conditions are met. If not, the BWP switching operation can be performed according to the switching information; if it is met, the switching information can be ignored, that is, the BWP switching operation is not performed; wherein the preset conditions can be set according to actual needs.

[0236] Exemplarily, the method can be applied to a variety of possible BWP switching scenarios. For example, the method can be applied to a scenario where a terminal device switches between an initial BWP and a dedicated BWP, or a scenario where a terminal device switches between multicast BWPs, or a scenario where a dedicated BWP (or initial BWP) and a multicast BWP are switched.

[0237] Example 4

[0238] In the fourth embodiment, a possible implementation will be described by taking the scenario where the method is applicable to a terminal device switching from an initial BWP, a dedicated BWP or a multicast BWP to a multicast BWP as an example.

[0239] Figure 9 This is a flow chart corresponding to the communication method provided in Example 4 of this application, such as Figure 9 Shown, including:

[0240] Step 901: The network device sends switching information to the terminal device, and accordingly, the terminal device can receive the switching information.

[0241] For example, the switching information may be the first information in Embodiments 1 to 3, which is used to instruct the terminal device to switch the second BWP to the first BWP.

[0242] In step 902, the terminal device determines whether the preset conditions are met. If the preset conditions are met, steps 903a and 904a are executed; if the preset conditions are not met, steps 903b and 904b are executed.

[0243] In one example, the terminal device determines whether a preset condition is met, which may mean that the terminal device determines whether at least one of the following is met: (1) when the first information is received, the terminal device is receiving a unicast transmission of a second service on the second BWP; wherein the priority of the first service is lower than or equal to the priority of the second service; or, the priority of the multicast transmission is lower than or equal to the priority of the unicast transmission. In this case, the second BWP may be a dedicated BWP, and the second service may be a unicast service or a multicast service. (2) when the first information is received, the terminal device is receiving a multicast transmission of a third service on the second BWP, and the priority of the first service is lower than or equal to the priority of the third service. In this case, the second BWP may be a multicast BWP, and the third service may be a multicast service. (3) when the first information is received, the terminal device is performing a random access process on the second BWP. In this case, the second BWP may be a dedicated BWP or an initial BWP.

[0244] If the terminal device is determined to meet at least one of (1)(2)(3), it means that the preset condition is met; if it is determined not to meet (1)(2)(3), it means that the preset condition is not met.

[0245] In this example, the priorities of various services can be pre-configured by the network device to the terminal device, or can also be agreed upon by the protocol. The priorities of unicast transmission and multicast transmission can also be pre-configured by the network device to the terminal device, or can also be agreed upon by the protocol.

[0246] Step 903a: The terminal device ignores the switching information, that is, does not perform BWP switching according to the first information.

[0247] Here, if the switching information is the first information in Example 1 to Example 3, then: in Example 1, the terminal device ignoring the first information can be understood as the terminal device ignoring DCI-1; in Example 2, the terminal device ignoring the first information can be understood as the terminal device ignoring DCI-2 (the first information is carried in DCI-2), or the terminal device ignores DCI-2 and the PDSCH scheduled by DCI-2 (the first information is carried in the PDSCH); in Example 3, the terminal device ignoring the first information can be understood as the terminal device ignoring DCI-3 (the first information is carried in DCI-3), or the terminal device ignores DCI-3 and the PDSCH scheduled by DCI-3 (the first information is carried in the PDSCH).

[0248] In step 904a, after the network device determines that the terminal device ignores the switching information, it can send a unicast transmission of the first service to the terminal device (i.e., send data of the first service to the terminal device via unicast); accordingly, the terminal device can receive the unicast transmission of the first service.

[0249] Here, there may be multiple ways for the network device to determine that the terminal device has ignored the first information. For example, after the terminal device ignores the first information, it may send a notification message to the network device, and then the network device may determine that the terminal device has ignored the first information based on the notification message. Among them, the notification information may be carried in a control message of the MAC layer, and the control message of the MAC layer may include a MAC subPDU. The MAC subPDU may include a MAC subheader and a MAC CE. The MAC subheader includes a logical channel identifier (LCID) field. The LCID field may be used to indicate the LCID. In an embodiment of the present application, a special LCID (such as LCID-1) may be introduced. When the LCID field indicates LCID-1, it indicates that the control message of the MAC layer is used to indicate that the terminal device has ignored the first information. Optionally, the MAC CE corresponding to the MAC subheader may be empty (i.e., the length of the field is 0).

[0250] Exemplarily, after the network device determines that the terminal device has ignored the first information, if the currently activated second BWP is a dedicated BWP, the network device can send a unicast transmission of the first service to the terminal device on the second BWP; or, it can also instruct the terminal device to switch to other dedicated BWPs, and then send a unicast transmission of the first service to the terminal device on other dedicated BWPs, without specific limitation.

[0251] Step 903b: The terminal device switches the activated BWP from the second BWP to the first BWP according to the first information.

[0252] At step 904b, the network device sends multicast transmission of the first service to the terminal device on the first BWP, and correspondingly, the terminal device receives the multicast transmission of the first service on the first BWP.

[0253] Here, the terminal device can determine whether the currently activated BWP (i.e., the second BWP) matches the first BWP. If the match (for example, the second BWP and the first BWP are the same BWP), the terminal device can receive the multicast transmission of the first service on the second BWP. If the match is not matched (for example, the second BWP and the first BWP are different BWP), the terminal device can switch the activated BWP from the second BWP to the first BWP according to the first information, and receive the multicast transmission of the first service on the first BWP.

[0254] In this way, when the terminal device receives the switching information, it can first determine whether to perform the operation with higher priority on the currently activated BWP. If yes, the BWP switching operation can be temporarily not performed, otherwise, the BWP switching operation can be performed, thereby effectively avoiding the interruption of the operation with higher priority.

[0255] In the embodiments of the present application, it is considered that after the terminal device receives the multicast service on the multicast BWP, if it still stays on the multicast BWP, there can be some problems. For example, from the perspective of service demand, since the multicast service is not always available, when the multicast service needs to be received, the terminal device can switch to the multicast BWP to receive the multicast service. However, after the multicast service transmission is completed, if the terminal device still stays on the multicast BWP (such as using the SCS, bandwidth, etc. corresponding to the multicast BWP), it can not meet the demand of other services, thereby affecting the reception of other services. For example, from the perspective of power consumption of the terminal device, the multicast service (such as video live broadcast) usually corresponds to a large amount of data, and thus the width of the multicast BWP required is large. After the video live broadcast is over, the normal service does not need such a large width, and if the terminal device still stays on the multicast BWP with a large width, it can cause large power consumption of the terminal device.

[0256] Based on this, the embodiments of the present application also provide a communication method, in which the terminal device can switch to the multicast BWP, and then fall back to a suitable BWP from the multicast BWP to solve the above problems. The terminal device can be switched to the multicast BWP in the manner described in the foregoing embodiments one to three, or can be switched to the multicast BWP in other possible manners.

[0257] Embodiment five

[0258] In Example 5, the example of a terminal device switching to a multicast BWP in the manner described in Examples 1 to 3 above is taken as an example, and the possible implementation of the terminal device falling back from a multicast BWP to other suitable BWPs is described in combination with Implementation Methods 1 and 2.

[0259] Implementation 1

[0260] In Implementation Method 1, the terminal device can decide to switch the active BWP from the first BWP to a third BWP. The third BWP can be pre-defined by the protocol, agreed upon between the network device and the terminal device, or indicated by the network device; for example, the third BWP can be the default BWP or the second BWP. In this approach, the terminal device decides to switch the active BWP from the first BWP to the third BWP, effectively reducing signaling overhead between the terminal device and the network device and enabling the terminal device to promptly fall back to an appropriate BWP.

[0261] In one example of this implementation, if the terminal device determines that multicast transmission of the first service has not been received on the first BWP within a first duration and DCI-4 has not been detected, the active BWP may be switched from the first BWP to a third BWP. DCI-4 is used to schedule multicast transmission of the first service, and DCI-4 may be scrambled using the G-RNTI associated with the first service. Specifically, the terminal device may start a timer at a first moment, and within a preset time period starting at the first moment, if multicast transmission of the first service has not been received on the first BWP and DCI-4 has not been detected, then at the end of the preset time period, the terminal device may determine that the timer has expired and switch the active BWP from the first BWP to the third BWP. If multicast transmission of the first service is performed on the first BWP and / or DCI-4 is detected within the preset time period, the timer is restarted. The duration of the timer is equal to the duration of the preset time period and equal to the first duration.

[0262] The above-mentioned first moment can be the moment when the first information is received, or it can be the moment when the activated BWP is switched to the first BWP, or it can be the end boundary of the subframe or time slot or micro-time slot or symbol or frame for receiving multicast transmission, or it can be other possible moments, which can depend on the internal implementation of the terminal device. The above-mentioned first duration can be indicated by the network device, such as the terminal device receives indication information from the network device, and the indication information is used to indicate the first duration; wherein the indication information can be carried in a system message or an RRC layer message or DCI, and the DCI can be encrypted by the G-RNTI of the first service. Alternatively, the first duration can also be pre-defined by the protocol.

[0263] In another example of the implementation, the terminal device can switch the active BWP from the first BWP to the third BWP if the terminal device does not detect the DCI-4 on the M continuous candidate time-frequency locations corresponding to the DCI-4. The value of M can be indicated by the network device or predefined by the protocol.

[0264] In another example of the implementation, the terminal device can start a timer at the second time, and switch the active BWP from the first BWP to the third BWP after the timer expires. The second time can be the time when the first information is received, or the time when the active BWP is switched to the first BWP, or the end boundary of the subframe or slot or mini-slot or symbol or frame of the multicast transmission, or other possible time, which can depend on the internal implementation of the terminal device. The duration of the timer can be the second duration, which can be indicated by the network device or predefined by the protocol.

[0265] In addition, in the implementation 1, after the terminal device switches the active BWP from the first BWP to the third BWP, the terminal device can further send a switching confirmation indication to the network device on the third BWP, to indicate that the terminal device has fallen back to the third BWP. Correspondingly, after the network device receives the switching confirmation indication on the third BWP, the network device can know that the terminal device has fallen back to the third BWP, so as to ensure that the terminal device and the network device have consistent understanding of the working BWP of the terminal device.

[0266] Implementation 2

[0267] In the implementation 2, the terminal device can send a request message to the network device, where the request message is used to request to perform BWP switching. Correspondingly, after the network device receives the request message, the network device can send a response message to the terminal device, and then the terminal device can switch the active BWP from the first BWP to the third BWP based on the response message of the network device. The terminal device can be triggered to send the request message to the network device in various ways. For example, if the terminal device determines that the multicast transmission of the first service is not received on the first BWP within the first duration, and the DCI-3 is not detected, the terminal device can send the request message to the network device. For another example, if the terminal device determines that the DCI-3 is not detected on the M continuous candidate time-frequency locations corresponding to the DCI-3, the terminal device can send the request message to the network device. The specific implementation can be referred to the description above. In this way, the terminal device switches the BWP according to the response message of the network device, so as to effectively improve the flexibility of network device control.

[0268] The implementation 2 is described in detail below in combination with the case 1 to the case 3.

[0269] Case 1

[0270] The network device and the terminal device may pre-agreed on a fallback BWP, or a protocol may pre-define a fallback BWP, such as a third BWP. Thus, a request message requesting a BWP switch can refer to a request to switch from the first BWP to the third BWP, or a request to fall back to the third BWP. Accordingly, after receiving the request message, the network device can determine whether to allow the terminal device to switch to the third BWP and send a response message to the terminal device based on the determination. For example, the response message may include a single bit of indication information. If the value of this bit is 1, it indicates that the terminal device is allowed to switch to the third BWP; if the value of this bit is 0, it indicates that the terminal device is not allowed to switch to the third BWP. For example, if the response message includes the identifier of the third BWP, it indicates that the terminal device is allowed to switch to the third BWP; if the response message does not include the identifier of the third BWP, it indicates that the terminal device is not allowed to switch to the third BWP. In other possible examples, if the network device determines that the terminal device is not allowed to switch to the third BWP, it may not send a response message. Accordingly, if the terminal device does not receive a response message, it can be known that the network device does not allow the terminal device to switch to the third BWP. For example, the network device may determine whether to allow the terminal device to switch to the third BWP based on various criteria, which are not limited in this embodiment of the present application.

[0271] In the above scenario 1, the request message may be a control message of the MAC layer, a control message of the RLC layer, a control message of the PDCP layer, or a message of the RRC layer (ie, an RRC message).

[0272] For example, when the request message is a MAC layer control message, the MAC layer control message may include a MAC sub-PDU. Figure 10a As shown, the MAC subPDU may include a MAC subheader and a MAC control element (CE). The MAC subheader includes an LCID field, which may be used to indicate an LCID. In the embodiment of the present application, a special LCID (e.g., LCID-2) may be introduced. When the LCID field indicates LCID-2, it indicates that the MAC layer control message is used to request the execution of a BWP handover. Optionally, the MAC CE corresponding to the MAC subheader may be empty (i.e., the length of the field is 0).

[0273] For another example, when the request message is a control message of the RLC layer or a control message of the PDCP layer, the control message of the RLC layer or the control message of the PDCP layer may be a control PDU. Figure 10bAs shown, the PDU may include a D / C field, a PDU type field, and a reserved field. The D / C field is used to indicate that the PDU is a control PDU, and the PDU type field is used to indicate the type of the PDU. In the embodiment of the present application, a special PDU type may be introduced. When the PDU type field indicates the special PDU type, it indicates that the PDU is used to request a BWP handover.

[0274] Scenario 2

[0275] The request message may include an identifier of a candidate BWP (e.g., the candidate BWP is the third BWP). Thus, the request message requesting BWP switching may refer to a request requesting switching from the first BWP to the third BWP. Accordingly, upon receiving the request message, the network device may determine whether to allow the terminal device to switch to the third BWP and send a response message to the terminal device based on the determination result. Scenario 2 differs from Scenario 1 in that the request message includes an identifier of a candidate BWP. Other than this difference, the two scenarios are mutually referential.

[0276] Scenario 3

[0277] The request message may include identifiers of multiple candidate BWPs. Thus, a request message requesting BWP switching may refer to a request requesting that the first BWP be switched to one of the multiple candidate BWPs. Accordingly, after receiving the request message, the network device may select a third BWP from the multiple candidate BWPs and send a response message to the terminal device, the response message including the identifier of the third BWP. The terminal device may then switch to the third BWP based on the response message. In other possible examples, if the response message does not include the identifier of any candidate BWP or the terminal device does not receive the response message, this indicates that the terminal device is not permitted to perform BWP switching. For example, the network device may select the third BWP from the multiple candidate BWPs based on various criteria, which are not limited in this embodiment of the present application.

[0278] In the above scenario 2 and scenario 3, the request message may be a control message of the MAC layer, a control message of the RLC layer, a control message of the PDCP layer, or a message of the RRC layer.

[0279] For example, when the request message is a MAC layer control message, the MAC layer control message may include a MAC subPDU. Figure 10cAs shown, the MAC subPDU may include a MAC subheader and a MAC CE. The MAC subheader includes an LCID field. The LCID field may be used to indicate an LCID. In the embodiment of the present application, a special LCID (such as LCID-2) may be introduced. When the LCID field indicates the special LCID, it indicates that the control message of the MAC layer is used to request to perform BWP switching. The MAC CE corresponding to the MAC subheader may include the identifiers of one or more candidate BWPs.

[0280] For another example, when the request message is a control message of the RLC layer or a control message of the PDCP layer, the control message of the RLC layer or the control message of the PDCP layer may be a control PDU. Figure 10d As shown, a control PDU may include a D / C field, a PDU type field, and a reserved field. The D / C field indicates that the PDU is a control PDU, and the PDU type field indicates the type of the PDU. In embodiments of the present application, a special PDU type may be introduced. When the PDU type field indicates this special PDU type, it indicates that the PDU is used to request BWP switching. The reserved field may include the identifiers of one or more candidate BWPs.

[0281] In addition, in implementation method 2, after the terminal device switches the activated BWP from the first BWP to the third BWP based on the response message of the network device, it can also send a switching confirmation indication to the network device on the third BWP to indicate that the terminal device has fallen back to the third BWP; accordingly, after the network device receives the switching confirmation indication from the third BWP, it can be known that the terminal device has completed the BWP switching, thereby ensuring that the terminal device and the network device have a consistent understanding of the working BWP of the terminal device.

[0282] Implementation 3

[0283] In Implementation 3, the terminal device can select a BWP from multiple candidate BWPs (e.g., select the third BWP) and switch the active BWP from the first BWP to the third BWP. The multiple candidate BWPs can be preconfigured by the network device and can include dedicated BWPs and / or multicast BWPs for the terminal device. In this implementation, the terminal device selects a BWP and switches to it, making the terminal device's implementation more flexible and facilitating the terminal device's fallback to a suitable BWP.

[0284] Here, there may be multiple bases or rules for the terminal device to select a BWP from multiple candidate BWPs. In one example, the terminal device may select a BWP based on the service requirements of subsequent transmission, and the service requirements may include the service data volume and / or the requirements for service delay. For example, if the service data volume is large, the terminal device may select a BWP with a larger width from multiple candidate BWPs; if the service data volume is small, the terminal device may select a BWP with a smaller width from multiple candidate BWPs. For another example, if the service has high latency requirements, the terminal device may select a BWP corresponding to a smaller subcarrier spacing from multiple candidate BWPs. It can be understood that when two or more BWPs among multiple candidate BWPs meet the conditions (for example, there are two or more BWPs with larger widths), which BWP is specifically selected may depend on the internal implementation of the terminal device.

[0285] In another example, a terminal device may select a BWP based on the measured reference signal quality of multiple candidate BWPs. For example, a BWP with a reference signal quality greater than or equal to a preset threshold may be selected from the multiple candidate BWPs. When two or more BWPs have a reference signal quality greater than or equal to the preset threshold, the specific BWP selected may depend on the internal implementation of the terminal device. The reference signal quality may be RSRP and / or RSRQ. The preset threshold may be preconfigured by the network device or predefined by the protocol.

[0286] In addition, in implementation method 3, after the terminal device switches the activated BWP from the first BWP to the third BWP, it can also send a switching confirmation indication to the network device on the third BWP to indicate that the terminal device has fallen back to the third BWP; accordingly, after the network device receives the switching confirmation indication from the third BWP, it can be known that the BWP selected by the terminal device from multiple candidate BWPs is the third BWP and that the terminal device has fallen back to the third BWP, thereby ensuring that the terminal device and the network device have a consistent understanding of the terminal device's working BWP.

[0287] It should be noted that in the above-mentioned Implementation 1, Implementation 2, or Implementation 3, the terminal device may send a handover confirmation indication on the third BWP in various ways. For example, the handover confirmation indication may be a MAC layer control message, which may include a MAC subPDU. In embodiments of the present application, a special LCID (e.g., LCID-3) may be introduced. When the LCID field of the MAC subPDU indicates LCID-3, it indicates that the MAC layer control message is a handover confirmation indication. Optionally, the MAC CE of the MAC subPDU may be empty. When the terminal device determines that there are available uplink resources on the third BWP, the MAC layer control message may be sent using the available uplink resources. For another example, the handover confirmation indication may correspond to one or more specific random access preambles (e.g., preamble 1). That is, preamble 1 may indicate that the terminal device has fallen back to the third BWP. Therefore, the terminal device sending the handover confirmation indication on the third BWP may mean that the terminal device sends preamble 1 on the third BWP. The corresponding relationship between the handover confirmation indication and the specific random access preamble code may be configured by the network device for the terminal device, or may be pre-defined by the protocol.

[0288] Regarding the above-mentioned embodiments 1 to 5, it should be noted that:

[0289] (1) The above-mentioned embodiments 1 to 5 may be implemented separately or in combination. For example, embodiment 1, embodiment 2, or embodiment 3 may be implemented in combination with embodiment 4; for another example, embodiment 1, embodiment 2, or embodiment 3 may be implemented in combination with embodiment 5; for another example, embodiment 4 and embodiment 5 may be implemented in combination; for another example, embodiment 1, embodiment 2, or embodiment 3 may be implemented in combination with embodiment 4 and embodiment 5.

[0290] (2) The above-mentioned embodiments 1 to 5 focus on describing the differences between different embodiments. Except for the differences, embodiments 1 to 5 can refer to each other.

[0291] (3) The step numbers in the flowcharts described in Examples 1 to 4 are merely examples of the execution process and do not limit the order in which the steps are executed. In the embodiments of this application, there is no strict execution order for steps that have no temporal dependencies. Furthermore, not all steps shown in the flowcharts are mandatory, and steps may be added or deleted based on actual needs.

[0292] The above mainly introduces the solution provided by the embodiment of the present application from the perspective of the interaction between the network device and the terminal device. It is understandable that in order to implement the above functions, the network device or the terminal device may include a hardware structure and / or software module that performs the corresponding functions. Those skilled in the art should easily appreciate that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the embodiments of the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in a hardware or computer software driven hardware manner depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0293] In the embodiments of the present application, the terminal device and the network device can be divided into functional units according to the above method examples. For example, each functional unit can be divided according to each function, or two or more functions can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or software functional units.

[0294] In the case of an integrated unit, Figure 11 A possible exemplary block diagram of the device involved in the embodiments of the present application is shown. Figure 11 As shown, apparatus 1100 may include a processing unit 1102 and a communication unit 1103. Processing unit 1102 is used to control and manage the operations of apparatus 1100. Communication unit 1103 is used to support communication between apparatus 1100 and other devices. Optionally, communication unit 1103, also known as a transceiver unit, may include a receiving unit and / or a transmitting unit, each configured to perform receiving and transmitting operations. Optionally, apparatus 1100 may also include a storage unit 1101 for storing program code and / or data of apparatus 1100.

[0295] The apparatus 1100 may be a terminal device in any of the aforementioned embodiments, or may be a chip disposed within the terminal device. The processing unit 1102 may support the apparatus 1100 in executing the actions of the terminal device in the aforementioned method examples. Alternatively, the processing unit 1102 may primarily execute the internal actions of the terminal device in the method examples, and the communication unit 1103 may support communication between the apparatus 1100 and a network device.

[0296] Specifically, in one embodiment, the communication unit 1103 is used to receive first information from a network device, wherein the first information is used to indicate receiving multicast transmission of a first service on a first BWP; the processing unit 1102 is used to switch the second BWP to the first BWP according to the first information; and the communication unit 1103 is also used to receive multicast transmission of the first service on the first BWP.

[0297] In a possible implementation manner of this embodiment, the first information is a first DCI, the first DCI is scrambled by a group radio G-RNTI associated with the first service, and the BWP corresponding to the G-RNTI is the first BWP.

[0298] In a possible implementation manner of this embodiment, the communication unit 1103 is further configured to receive second information from the network device, where the second information is used to configure a correspondence between the G-RNTI and the first BWP.

[0299] In a possible implementation of this embodiment, the first information includes configuration information of the first BWP; wherein, the configuration information of the first BWP includes frequency domain starting position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain; or, the configuration information of the first BWP includes a parameter resource indication value RIV corresponding to the first BWP, and the RIV is used to indicate the frequency domain offset position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information of the first BWP is used to determine the frequency domain starting position information of the first BWP.

[0300] In a possible implementation of this embodiment, the first information includes an identifier of a first BWP; the communication unit 1103 is further used to receive third information from a network device; wherein the third information is used to configure at least one BWP and an identifier of the at least one BWP, and the at least one BWP includes the first BWP.

[0301] In a possible implementation of this embodiment, the first information includes an identifier of the group to which the first BWP belongs and an identifier of the first BWP within the group; the communication unit 1103 is further used to receive fourth information from the network device; wherein the fourth information is used to configure at least one BWP, an identifier of the group to which the at least one BWP belongs, and an identifier of the at least one BWP within the group to which the at least one BWP belongs, and the at least one BWP includes the first BWP.

[0302] In a possible implementation of this embodiment, the first information is carried in the second DCI, and the second DCI is encrypted by the G-RNTI associated with the first service; or, the first information is carried in a control message of the MAC layer or a control message of the RLC layer or a control message of the PDCP layer.

[0303] In a possible implementation of this embodiment, the processing unit 1102 is specifically used to switch the second BWP to the first BWP according to the first information when it is determined that the following first to third items are not met: the first item, when the first information is received, the unicast transmission of the second service is being received on the second BWP; wherein the priority of the first service is lower than or equal to the priority of the second service; or, the priority of the multicast transmission is lower than or equal to the priority of the unicast transmission; the second item, when the first information is received, the multicast transmission of the third service is being received on the second BWP, and the priority of the first service is lower than or equal to the priority of the third service; the third item, when the first information is received, the random access process is being performed on the second BWP.

[0304] In a possible implementation of this embodiment, the communication unit 1103 is further used to send a request message to the network device, where the request message is used to request to perform BWP switching; and receive a response message from the network device, and switch the first BWP to the third BWP according to the response message.

[0305] In a possible implementation of this embodiment, the request message includes an identifier of at least one candidate BWP; the request message is used to request execution of BWP switching, including: the request message is used to request switching of the first BWP to one of the at least one candidate BWP; the response message includes an identifier of a third BWP, and the third BWP is determined based on the at least one candidate BWP.

[0306] In a possible implementation of this embodiment, the communication unit 1103 is specifically used to determine that if the multicast transmission of the first service is not received on the first BWP within the first time period and the third DCI is not detected, then send a request message to the network device; or, if the third DCI is not detected at M consecutive candidate time-frequency positions corresponding to the third DCI, then send a request message to the network device; M is a positive integer; wherein the third DCI is used to schedule the multicast transmission of the first service.

[0307] In a possible implementation of this embodiment, the processing unit 1102 is specifically used to determine that if the multicast transmission of the first service is not received on the first BWP within the first time period and the third DCI is not detected, the first BWP is switched to the third BWP; or, if the third DCI is not detected at M consecutive candidate time-frequency positions corresponding to the third DCI, the first BWP is switched to the third BWP; M is a positive integer; wherein the third DCI is used to schedule the multicast transmission of the first service.

[0308] The apparatus 1100 may be a network device (e.g., the first network device or the second network device) in any of the above embodiments, or may be a chip disposed within the network device. The processing unit 1102 may support the apparatus 1100 in executing the actions of the network device in each of the above method examples. Alternatively, the processing unit 1102 may primarily execute the internal actions of the network device in the method examples, and the communication unit 1103 may support communication between the apparatus 1100 and other devices.

[0309] Specifically, in one embodiment, the communication unit 1103 is configured to send first information to the terminal device, where the first information is used to instruct to receive multicast transmission of the first service on the first BWP; and send multicast transmission of the first service on the first BWP.

[0310] In a possible implementation of this embodiment, the first information is a first DCI, and the first DCI is scrambled by a G-RNTI associated with the first service; and the BWP corresponding to the G-RNTI is the first BWP.

[0311] In a possible implementation manner of this embodiment, the communication unit 1103 is further configured to send second information to the terminal device, where the second information is used to configure a correspondence between the G-RNTI and the first BWP.

[0312] In a possible implementation of this embodiment, the first information includes configuration information of the first BWP; wherein, the configuration information of the first BWP includes frequency domain starting position information of the first BWP and bandwidth information occupied by the first BWP in the frequency domain; or, the configuration information of the first BWP includes a parameter resource indication value RIV corresponding to the first BWP, and the RIV is used to indicate the frequency domain offset position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information is used to determine the frequency domain starting position information.

[0313] In a possible implementation of this embodiment, the first information includes an identifier of a first BWP; the communication unit 1103 is further used to send third information to the terminal device; wherein the third information is used to configure at least one BWP and an identifier of the at least one BWP, and the at least one BWP includes the first BWP.

[0314] In a possible implementation of this embodiment, the first information includes an identifier of the group to which the first BWP belongs and an identifier of the first BWP within the group; the communication unit 1103 is also used to send fourth information to the terminal device; wherein the fourth information is used to configure the at least one BWP, the identifier of the group to which the at least one BWP belongs, and the identifier of the at least one BWP within the group to which the at least one BWP belongs, and the at least one BWP includes the first BWP.

[0315] In a possible implementation of this embodiment, the first information is carried in the second DCI, and the second DCI is encrypted by the G-RNTI associated with the first service; or, the first information is carried in a control message of the MAC layer or a control message of the RLC layer or a control message of the PDCP layer.

[0316] In a possible implementation of this embodiment, the communication unit 1103 is further used to receive a request message from the terminal device, wherein the request message is used to request to perform BWP switching; and send a response message to the terminal device according to the request message, wherein the response message is used to indicate that the first BWP is switched to the third BWP.

[0317] In a possible implementation of this embodiment, the request message includes an identifier of at least one candidate BWP; the request message is used to request execution of BWP switching, including: the request message is used to request switching the first BWP to one of the at least one candidate BWP; the response message includes an identifier of a third BWP, and the third BWP is determined based on the at least one candidate BWP.

[0318] It should be understood that the division of units in the above device is merely a division of logical functions. In actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. Moreover, the units in the device can all be implemented in the form of software called through processing elements; or they can all be implemented in the form of hardware; or some units can be implemented in the form of software called through processing elements, and some units can be implemented in the form of hardware. For example, each unit can be a separately established processing element, or it can be integrated into a certain chip of the device. In addition, it can also be stored in the memory in the form of a program, called by a certain processing element of the device and perform the function of the unit. In addition, all or part of these units can be integrated together, or they can be implemented independently. The processing element described here can also be a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each unit above can be implemented by the integrated logic circuit of the hardware in the processor element or in the form of software called through the processing element.

[0319] In one example, the unit in any of the above devices may be one or more integrated circuits configured to implement the above method, such as one or more application-specific integrated circuits (ASICs), one or more digital singnal processors (DSPs), one or more field programmable gate arrays (FPGAs), or a combination of at least two of these integrated circuit forms. For another example, when the unit in the device can be implemented in the form of a processing element scheduler, the processing element can be a processor, such as a general-purpose central processing unit (CPU), or other processor that can call a program. For another example, these units can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0320] The above-mentioned receiving unit is an interface circuit of the device, which is used to receive signals from other devices. For example, when the device is implemented as a chip, the receiving unit is the interface circuit of the chip used to receive signals from other chips or devices. The above-mentioned sending unit is an interface circuit of the device, which is used to send signals to other devices. For example, when the device is implemented as a chip, the sending unit is the interface circuit of the chip used to send signals to other chips or devices.

[0321] Please refer to Figure 12 , which is a structural diagram of a terminal device provided in an embodiment of the present application. It can be the terminal device in the above embodiment, used to implement the operations of the terminal device in the above embodiment. Figure 12 As shown, the terminal device includes an antenna 1210, a radio frequency (RF) section 1220, and a signal processing section 1230. Antenna 1210 is connected to RF section 1220. In the downlink direction, RF section 1220 receives information sent by a network device via antenna 1210 and sends the information to signal processing section 1230 for processing. In the uplink direction, signal processing section 1230 processes the terminal device information and sends it to RF section 1220. RF section 1220 then processes the terminal device information and sends it to the network device via antenna 1210.

[0322] The signal processing unit 1230 may include a modem subsystem for processing data at various communication protocol layers; a central processing unit for processing the terminal device's operating system and application layers; and other subsystems, such as a multimedia subsystem for controlling the terminal device's camera and screen display, and a peripheral subsystem for connecting to other devices. The modem subsystem may be a separate chip.

[0323] The modem subsystem may include one or more processing elements 1231, such as a main control CPU and other integrated circuits. Furthermore, the modem subsystem may include a storage element 1232 and an interface circuit 1233. Storage element 1232 is used to store data and programs. However, the program used to execute the method performed by the terminal device in the above method may not be stored in storage element 1232 but rather in a memory external to the modem subsystem, and loaded by the modem subsystem when in use. Interface circuit 1233 is used to communicate with other subsystems.

[0324] The modem subsystem can be implemented using a chip comprising at least one processing element and an interface circuit, wherein the processing element is configured to execute each step of any of the methods performed by the terminal device described above, and the interface circuit is configured to communicate with other devices. In one implementation, the unit for implementing each step of the method described above can be implemented as a processing element scheduler. For example, the terminal device may include a processing element and a storage element, with the processing element invoking a program stored in the storage element to execute the method performed by the terminal device in the above method embodiments. The storage element can be a storage element located on the same chip as the processing element, i.e., an on-chip storage element.

[0325] In another implementation, the program for executing the method executed by the terminal device in the above method can be stored in a memory element on a different chip from the processing element, i.e., an off-chip memory element. In this case, the processing element calls or loads the program from the off-chip memory element to the on-chip memory element to call and execute the method executed by the terminal device in the above method embodiment.

[0326] In another implementation, the unit of the terminal device that implements each step of the above method may be configured as one or more processing elements, which are provided in the modem subsystem. The processing elements here may be integrated circuits, such as one or more ASICs, one or more DSPs, one or more FPGAs, or a combination of these integrated circuits. These integrated circuits may be integrated together to form a chip.

[0327] The units that implement the various steps of the above method in the terminal device can be integrated together and implemented in the form of a SOC chip, which is used to implement the above method. The chip can integrate at least one processing element and a storage element, and the method performed by the terminal device can be implemented by the processing element calling the program stored in the storage element; alternatively, the chip can integrate at least one integrated circuit to implement the method performed by the terminal device; alternatively, the above implementation methods can be combined, with the functions of some units being implemented by the processing element calling the program, and the functions of some units being implemented by the integrated circuit.

[0328] As can be seen, the above-mentioned apparatus for a terminal device may include at least one processing element and an interface circuit, wherein the at least one processing element is used to execute any of the methods provided in the above method embodiments. The processing element may execute some or all of the steps executed by the terminal device in a first manner: by calling a program stored in a storage element; or in a second manner: by executing some or all of the steps executed by the terminal device through the hardware integrated logic circuit in the processor element in combination with instructions. Of course, the first and second manners may also be combined to execute some or all of the steps executed by the terminal device.

[0329] The processing element here is the same as described above and can be implemented by a processor. The function of the processing element can be Figure 11 The processing unit described in the preceding claims has the same function. For example, the processing element may be a general-purpose processor, such as a CPU, or one or more integrated circuits configured to implement the above method, such as one or more ASICs, or one or more microprocessors DSPs, or one or more FPGAs, or a combination of at least two of these integrated circuit forms. The storage element may be implemented by a memory, and the function of the storage element may be the same as Figure 11 The function of the storage unit described in the above is the same. The storage element can be realized by a memory, and the function of the storage element can be the same as Figure 11 The storage element can be a single memory or a collective term for multiple memories.

[0330] Figure 12 The terminal equipment shown is capable of Figure 5 、 Figure 7 、 Figure 8 or Figure 9 The illustrated method embodiment involves various processes of a terminal device. Figure 12 The operations and / or functions of the various modules in the terminal device shown are for implementing the corresponding processes in the above method embodiments. For details, please refer to the description in the above method embodiments. To avoid repetition, detailed description is appropriately omitted here.

[0331] Please refer to Figure 13 , which is a schematic diagram of the structure of a network device provided in an embodiment of the present application. It is used to implement the operation of the network device (such as the first network device or the second network device) in the above embodiment. Figure 13 As shown, the network device includes an antenna 1301, a radio frequency device 1302, and a baseband device 1303. Antenna 1301 is connected to radio frequency device 1302. In the uplink direction, radio frequency device 1302 receives information sent by terminal devices via antenna 1301 and sends the information to baseband device 1303 for processing. In the downlink direction, baseband device 1303 processes the information from the terminal devices and sends it to radio frequency device 1302. Radio frequency device 1302 then processes the information and sends it to the terminal devices via antenna 1301.

[0332] The baseband device 1303 may include one or more processing elements 13031, such as a main control CPU and other integrated circuits. Furthermore, the baseband device 1303 may also include a storage element 13032 and an interface 13033. The storage element 13032 is used to store programs and data; the interface 13033 is used to exchange information with the radio frequency device 1302. The interface 13033 may be, for example, a common public radio interface (CPRI). The above-mentioned apparatus for a network device may be located in the baseband device 1303. For example, the above-mentioned apparatus for a network device may be a chip on the baseband device 1303, the chip including at least one processing element and an interface circuit, wherein the processing element is used to execute each step of any of the methods performed by the above-mentioned network device, and the interface circuit is used to communicate with other devices. In one implementation, the unit for implementing each step of the above-mentioned method in the network device may be implemented in the form of a processing element scheduler. For example, the apparatus for a network device includes a processing element and a storage element, and the processing element calls a program stored in the storage element to execute the method performed by the network device in the above-mentioned method embodiment. The storage element may be a storage element on the same chip as the processing element, ie, an on-chip storage element, or a storage element on a different chip from the processing element, ie, an off-chip storage element.

[0333] In another implementation, the unit of the network device that implements each step of the above method may be configured as one or more processing elements, which are provided on the baseband device. The processing elements here may be integrated circuits, such as one or more ASICs, one or more DSPs, one or more FPGAs, or a combination of these integrated circuits. These integrated circuits may be integrated together to form a chip.

[0334] The units for implementing the steps in the above method of the network device can be integrated together in the form of a system on a chip (SOC), for example, a baseband device includes the SOC chip, which is used to implement the above method. At least one processing element and a storage element can be integrated in the chip, and the method implemented by the network device above is implemented in the form of the processing element calling the stored program of the storage element; or, at least one integrated circuit can be integrated in the chip, which is used to implement the method executed by the network device above; or, in combination with the above implementation manner, part of the functions of the units are implemented in the form of the processing element calling the program, and part of the functions of the units are implemented in the form of the integrated circuit.

[0335] It can be seen that the above apparatus for the network device can include at least one processing element and an interface circuit, wherein the at least one processing element is used to execute the method executed by any one of the network devices provided in the above method embodiments. The processing element can execute part or all of the steps of the network device in the following first mode: calling the program stored in the storage element; or in the following second mode: executing part or all of the steps of the network device by the integrated logic circuit of the hardware in the processor element in combination with the instructions; of course, part or all of the steps of the network device above can also be executed in combination of the first mode and the second mode.

[0336] The processing element herein can be implemented by a processor as described above, and the functions of the processing element can be the same as the functions of the processing unit described in Figure 11 . Illustratively, the processing element can be a general-purpose processor such as a CPU, and can also be one or more integrated circuits configured to implement the above method, such as one or more ASICs, or one or more microprocessors DSPs, or one or more FPGAs, etc., or a combination of at least two of these forms of integrated circuits. The storage element can be implemented by a memory, and the functions of the storage element can be the same as the functions of the storage unit described in Figure 11 . The storage element can be implemented by a memory, and the functions of the storage element can be the same as the functions of the storage unit described in Figure 11 . The storage element can be one memory, or collectively refer to multiple memories.

[0337] Figure 13 The network device shown can implement the processes of the method embodiments shown in Figure 5 , Figure 7 , Figure 8 or Figure 9 . Figure 13The operations and / or functions of the modules in the network device are respectively for implementing the corresponding processes in the above method embodiments. For details, please refer to the description in the above method embodiments. To avoid repetition, detailed description is appropriately omitted here.

[0338] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0339] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0340] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0341] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0342] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A partial bandwidth (BWP) switching method, characterized in that: The method is applicable to a terminal device, and includes: Receiving first information from a network device, the first information being used to indicate receiving a multicast transmission of a first service on a first BWP; wherein the first information is carried in downlink control information DCI, and the DCI is scrambled by a group radio network temporary identifier G-RNTI associated with the first service; Switching the second BWP to the first BWP according to the first information; A multicast transmission of the first service is received on the first BWP.

2. The method according to claim 1, characterized in that The BWP corresponding to the G-RNTI is the first BWP.

3. The method according to claim 2, characterized in that The method further comprises: Second information is received from the network device, where the second information is used to configure a correspondence between the G-RNTI and the first BWP.

4. The method according to claim 1, wherein The first information includes configuration information of the first BWP; The configuration information of the first BWP includes the frequency domain starting position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain; or, the configuration information of the first BWP includes the parameter resource indication value RIV corresponding to the first BWP, and the RIV is used to indicate the frequency domain offset position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information is used to determine the frequency domain starting position information.

5. The method according to claim 1, wherein The first information includes an identifier of the first BWP; The method further includes: receiving third information from the network device; wherein the third information is used to configure at least one BWP and an identifier of the at least one BWP, and the at least one BWP includes the first BWP.

6. The method according to claim 1, characterized in that The first information includes an identifier of a group to which the first BWP belongs and an identifier of the first BWP within the group; The method also includes: receiving fourth information from the network device; wherein the fourth information is used to configure at least one BWP, an identifier of a group to which the at least one BWP belongs, and an identifier of the at least one BWP within the group to which the at least one BWP belongs, and the at least one BWP includes the first BWP.

7. The method according to claim 1, characterized in that Switching the second BWP to the first BWP according to the first information includes: When it is determined that multiple of the following conditions are not met, the second BWP is switched to the first BWP according to the first information: When the first information is received, a unicast transmission of a second service is being received on the second BWP; wherein the priority of the first service is lower than or equal to the priority of the second service; or, the priority of the multicast transmission is lower than or equal to the priority of the unicast transmission; When the first information is received, a multicast transmission of a third service is being received on the second BWP, and a priority of the first service is lower than or equal to a priority of the third service; When the first information is received, a random access procedure is being performed on the second BWP.

8. The method according to any one of claims 1 to 7, characterized in that The method further comprises: Sending a request message to the network device, wherein the request message is used to request execution of a BWP switch; A response message is received from the network device, and the first BWP is switched to a third BWP according to the response message.

9. The method according to claim 8, characterized in that The request message includes an identifier of at least one candidate BWP; The request message is used to request execution of BWP switching, including: the request message is used to request switching the first BWP to one of the at least one candidate BWP; The response message includes an identifier of a third BWP, where the third BWP is determined based on the at least one candidate BWP.

10. The method according to claim 8, characterized in that Sending a request message to the network device includes: determining that the multicast transmission of the first service is not received on the first BWP within a first duration and that the third DCI is not detected, sending a request message to the network device; or If the third DCI is not detected at M consecutive candidate time-frequency positions corresponding to the third DCI, a request message is sent to the network device; M is a positive integer; The third DCI is used to schedule multicast transmission of the first service.

11. The method according to any one of claims 1 to 7, characterized in that The method further comprises: determining that the multicast transmission of the first service is not received on the first BWP within a first duration and that the third DCI is not detected, switching the first BWP to a third BWP; or If the third DCI is not detected at M consecutive candidate time-frequency positions corresponding to the third DCI, the first BWP is switched to the third BWP; M is a positive integer; The third DCI is used to schedule multicast transmission of the first service.

12. A communication method, characterized in that: The method is applicable to a network device, and includes: Sending first information to a terminal device, where the first information is used to indicate receiving a multicast transmission of a first service on a first BWP; wherein the first information is carried in downlink control information DCI, and the DCI is scrambled by a group radio network temporary identifier G-RNTI associated with the first service; A multicast transmission of the first service is sent on the first BWP.

13. The method according to claim 12, characterized in that The BWP corresponding to the G-RNTI is the first BWP.

14. The method according to claim 13, characterized in that The method further comprises: Send second information to the terminal device, where the second information is used to configure the correspondence between the G-RNTI and the first BWP.

15. The method according to claim 12, characterized in that The first information includes configuration information of the first BWP; The configuration information of the first BWP includes the frequency domain starting position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain; or, the configuration information of the first BWP includes the parameter resource indication value RIV corresponding to the first BWP, and the RIV is used to indicate the frequency domain offset position information of the first BWP and the bandwidth information occupied by the first BWP in the frequency domain, and the frequency domain offset position information is used to determine the frequency domain starting position information.

16. The method according to claim 12, characterized in that The first information includes an identifier of the first BWP; The method further includes: sending third information to the terminal device; wherein the third information is used to configure at least one BWP and an identifier of the at least one BWP, and the at least one BWP includes the first BWP.

17. The method according to claim 12, wherein: The first information includes an identifier of a group to which the first BWP belongs and an identifier of the first BWP within the group; The method also includes: sending fourth information to the terminal device; wherein the fourth information is used to configure at least one BWP, an identifier of a group to which the at least one BWP belongs, and an identifier of the at least one BWP within the group to which the at least one BWP belongs, and the at least one BWP includes the first BWP.

18. The method according to any one of claims 12 to 17, characterized in that The method further comprises: receiving a request message from the terminal device, wherein the request message is used to request execution of a BWP switch; A response message is sent to the terminal device according to the request message, where the response message is used to instruct to switch the first BWP to a third BWP.

19. The method according to claim 18, characterized in that The request message includes an identifier of at least one candidate BWP; The request message is used to request execution of BWP switching, including: the request message is used to request switching the first BWP to one of the at least one candidate BWP; The response message includes an identifier of a third BWP, where the third BWP is determined based on the at least one candidate BWP.

20. A communication device, characterized in that: The method comprises means for performing the steps of the method according to any one of claims 1 to 11.

21. A communication device, characterized in that: Comprising means for performing the steps of the method according to any one of claims 12 to 19.

22. A communication device, characterized in that: The system comprises at least one processor and an interface circuit, wherein the at least one processor is configured to communicate with other devices through the interface circuit and execute the method according to any one of claims 1 to 11.

23. A communication device, characterized in that: The system comprises at least one processor and an interface circuit, wherein the at least one processor is configured to communicate with other devices through the interface circuit and execute the method according to any one of claims 12 to 19.

24. A computer-readable storage medium, characterized in that The method comprises a program, and when the program is executed by a processor, the method according to any one of claims 1 to 19 is executed.

25. A computer program product, characterized in that When a computer reads and executes the computer program or instructions in the computer program product, the method according to any one of claims 1 to 19 is performed.

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