Access switching method and device

Abstract

The invention provides an access switching method and device. The method can be applied to a terminal device, and the method comprises the steps that the terminal device receives first information, the first information is used for indicating a first network device to configure confirmation information of uplink authorization for the terminal device, and the first network device is a target network device to be accessed and switched by the terminal device. And the terminal device determines the first uplink authorization configured by the first network device for the terminal device. And the terminal equipment switches to the first network equipment according to the first uplink authorization. Wherein the first uplink authorization comprises a first time domain resource, the first time domain resource is located in a first time period, and the first time period is a time period when the terminal device executes switching to the first network device. Therefore, the time occupied by the first time domain resource is less, and the resource waste in the process of switching the terminal equipment to the first network equipment can be reduced.

Description

Technical Field

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

[0002] In the terrestrial network, when the terminal device detects that the signal quality of the current cell has deteriorated or the quality of the adjacent cell has improved, the terminal device reports a signal quality measurement report to the currently connected network device. After receiving the measurement report, the network device selects a target cell for the terminal device and informs the terminal device. Thus, the terminal device performs a switch between the target cell and the current cell.

[0003] However, in non-terrestrial networks, the distance between satellites and the ground is relatively long, and the round-trip transmission time of signals can usually reach several milliseconds or even tens of milliseconds. If the terminal device still uses the cell switching method in the terrestrial network to switch cells, it will cause a long switching delay.

[0004] Therefore, how to switch terminal devices in non-terrestrial networks is still a problem that needs to be solved urgently. Summary of the invention

[0005] The embodiments of the present application provide an access switching method and apparatus, which can reduce resource waste during the access switching process of a terminal device.

[0006] In the first aspect, an embodiment of the present application provides an access switching method, which can be executed by a terminal device. The terminal device here can refer to the terminal device itself, or a processor, module, chip, or chip system that implements the method in the terminal device. In the method, the terminal device receives a first message, and the first message is used to indicate confirmation information that the first network device configures an uplink authorization for the terminal device. The first network device is the target network device to be accessed and switched by the terminal device. The first uplink authorization includes a first time domain resource, and the first time domain resource is located in a first time period. The first time period is the time period in which the terminal device performs switching to the first network device. The terminal device determines the first uplink authorization configured by the first network device for the terminal device based on the first information. The terminal device switches to the first network device based on the first uplink authorization.

[0007] In the embodiment of the present application, the first time domain resource in the first uplink grant used when the terminal device switches to the first network device is located in the first time period, and the first time period is the time period during which the terminal device switches to the first network device. Thus, the first time domain resource occupies less time, which can reduce resource waste when the terminal device switches to the first network device.

[0008] In addition, before the terminal device switches to the first network device, the first network device determines the first uplink authorization configured for the terminal device, so that when the terminal device needs to switch to the first network device, it can directly switch to the first network device according to the determined first uplink authorization, thereby reducing the switching delay of the terminal device.

[0009] In an optional implementation, the terminal device switches to the first network device according to the first uplink authorization, including: receiving a cell switching command from the second network device, sending uplink data to the first network device according to the first uplink authorization to access the first network device, the second network device being a network device currently providing services to the terminal device. That is, the terminal device switches to the first network device according to the determined first uplink authorization to maintain communication continuity.

[0010] In an optional implementation, in the manner in which the terminal device receives a cell switching command and switches to the first network device, the terminal device may also receive a first indication before switching to the first network device according to the first uplink authorization, the first indication being used to indicate that the first network device has activated the first uplink authorization. In other words, the terminal device may also determine that the first uplink authorization has been activated according to the received first indication, so that when the cell switching command is received, the terminal device switches to the first network device according to the first uplink authorization configured for the terminal device by the first network device and activated.

[0011] In another optional implementation, the terminal device switches to the first network device based on the first uplink authorization, including: when the first condition is met, sending second information, the second information is used to request activation of the first uplink authorization configured by the first network device for the terminal device, the first condition being that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, and the second network device is the network device currently providing services to the terminal device; receiving third information, the third information is used to indicate that the first network device has activated the first uplink authorization; when the second condition is met, sending uplink data to the first network device based on the first uplink authorization to access the first network device, the second condition being that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold.

[0012] The signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, and the terminal device determines that it may switch to the first network device, so it sends the second information to request activation of the first uplink authorization configured by the first network device for the terminal device. Thus, the terminal device receives the third information and learns that the first uplink authorization has been activated by the first network device. Furthermore, when the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, that is, when it is determined that it is necessary to switch to the first network device, the terminal device switches to the first network device according to the first uplink authorization configured by the first network device for the terminal device and activated, so as to maintain the continuity of communication.

[0013] In another optional implementation, the terminal device switches to the first network device according to the first uplink authorization, including: when a first condition is met, sending second information, the second information is used to request activation of the first uplink authorization configured by the first network device for the terminal device, the first condition being that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, and the second network device is the network device currently providing services for the terminal device; receiving third information, the third information is used to indicate that the first network device has activated the first uplink authorization; when receiving a cell switching command from the second network device, sending uplink data to the first network device according to the first uplink authorization to access the first network device.

[0014] It can be seen that after the terminal device learns through the second information and the third information that the first uplink authorization configured by the first network device for the terminal device has been activated, and determines whether to switch to the first network device based on whether a cell switching command is received from the second network device.

[0015] In an optional implementation, the terminal device receives the first threshold and the second threshold corresponding to the first network device; or receives the first threshold corresponding to the first network device. This method is conducive to the terminal device performing conditional switching-based non-random access to the first network device according to the first condition and the second condition, or according to the first condition.

[0016] In an optional implementation manner, the first information is also used to indicate a first uplink authorization.

[0017] In another optional implementation, the terminal device determines the first uplink authorization configured by the first network device for the terminal device, including: receiving fourth information, the fourth information being used to indicate the first uplink authorization; and determining, based on the fourth information, the first uplink authorization configured by the first network device for the terminal device.

[0018] It can be seen that the terminal device can obtain the first uplink authorization configured by the first network device for the terminal device through the first information, or determine the first uplink authorization configured by the first network device for the terminal device according to the fourth information.

[0019] In an optional implementation, the start time of the first time period is the time when the terminal device sends the measurement report to the second network device, and the end time is the time when the terminal device accesses the first network device.

[0020] In the second aspect, the embodiment of the present application also provides an access switching method, which can be applied to a third network device, where the third network device can refer to the third network device itself, or a processor, module, chip, or chip system that implements the method in the third network device. In the method, the third network device sends fifth information to the first network device, and the fifth information is used to request the first network device to configure an uplink authorization for the terminal device. The fifth information includes information for indicating a first time period, and the time domain resources in the uplink authorization are within the first time period. The first time period is the time period in which the terminal device performs a switch to the first network device, and the first network device is the destination network device to be accessed and switched by the terminal device. The third network device receives the first information from the first network device and sends the first information, and the first information is used to indicate the confirmation information that the first network device configures the uplink authorization for the terminal device.

[0021] In the embodiment of the present application, the third network device requests the first network device to configure an uplink authorization for the terminal device through the fifth information, and the fifth information includes information for indicating the first time period, and the time domain resources in the uplink authorization are within the first time period, and the first time period is the time period in which the terminal device performs a handover to the first network device. This is conducive to the first network device configuring the uplink authorization for the terminal device according to the first time period to occupy less time, which is conducive to reducing resource waste.

[0022] In an optional implementation manner, the first information is also used to indicate the first uplink authorization configured by the first network device for the terminal device. This approach is conducive to the terminal device obtaining the first uplink authorization according to the first information.

[0023] In an optional implementation, the third network device receives first information from the first network device, and after sending the first information, receives second information and sends the second information to the first network device, where the second information is used to request activation of the first uplink authorization configured by the first network device for the terminal device. The third network device receives third information from the first network device and sends the third information, where the third information is used to indicate that the first network device has activated the first uplink authorization.

[0024] In an optional implementation manner, the third network device sends the first threshold and the second threshold corresponding to the first network device, or sends the first threshold corresponding to the first network device.

[0025] In an optional implementation, the start time of the first time period is the time when the terminal device sends the measurement report to the second network device, and the end time is the time when the terminal device accesses the first network device.

[0026] In a third aspect, an embodiment of the present application further provides an access switching method, which can be applied to a first network device, where the first network device can refer to the first network device itself, or a processor, module, chip, or chip system that implements the method in the first network device. In the method, the first network device receives fifth information from the third network device, the fifth information is used to request the first network device to configure an uplink authorization for the terminal device, the fifth information includes information for indicating a first time period, the time domain resources in the uplink authorization are located within the first time period, the first time period is the time period in which the terminal device performs a switch to the first network device, and the first network device is the target network device to be accessed and switched by the terminal device. The first network device sends first information to the third network device, the first information is used to indicate confirmation information that the first network device configures the uplink authorization for the terminal device. The first network device receives uplink data from the terminal device according to the first uplink authorization configured for the terminal device, the first uplink authorization includes a first time domain resource, and the first time domain resource is located within the first time period.

[0027] In an embodiment of the present application, the first network device receives fifth information for requesting to configure an uplink authorization for the terminal device, and indicates confirmation information that the first network device configures the uplink authorization for the terminal device through the first information. The fifth information includes information for indicating the first time period, and the time domain resources in the uplink authorization are located within the first time period, and the first time period is the time period in which the terminal device performs a handover to the first network device. Thus, the first time domain resources included in the first uplink authorization configured by the first network device for the terminal device are determined according to the first time period and are located within the first time period, so the first time domain resources occupy less time, which can reduce resource waste.

[0028] In an optional implementation manner, the first information is also used to indicate the first uplink authorization. This approach can reduce signaling overhead.

[0029] In an optional implementation, the first network device sends fourth information at a first moment before receiving uplink data from the terminal device according to the first uplink authorization configured for the terminal device, the fourth information being used to indicate the first uplink authorization, and the first moment being later than or equal to the start moment of the first time period. It can be seen that the first network device may also indicate the first uplink authorization configured for the terminal device through fourth information different from the first information.

[0030] In an optional implementation, the first network device sends a first indication before receiving uplink data from the terminal device based on the first uplink authorization configured for the terminal device when a third condition is met, and the first indication is used to indicate that the first network device has activated the first uplink authorization; the third condition is that the current time is within a first time period; or, the third condition is: the distance between the terminal device and the first network device is less than or equal to a first preset value, and / or the distance between the terminal device and the second network device is greater than a second preset value, and the second network device is a network device that currently provides services to the terminal device.

[0031] In an optional implementation, the first network device receives second information from a third network device before receiving uplink data from the terminal device according to the first uplink authorization configured for the terminal device, the second information being used to request activation of the first uplink authorization. The first network device sends third information to the third network device, the third information being used to indicate that the first network device has activated the first uplink authorization.

[0032] It can be seen that the first network device can actively activate the first uplink authorization when the third condition is met, and indicate to the terminal device through the first indication that the first uplink authorization has been activated. Alternatively, when the first network device receives the second information for requesting activation of the first uplink authorization, it activates the first uplink authorization and indicates through the third information that the first uplink authorization has been activated.

[0033] In an optional implementation, the start time of the first time period is the time when the terminal device sends a measurement report to the second network device, and the end time is the time when the terminal device accesses the first network device. The second network device is the network device currently providing services to the terminal device.

[0034] In a fourth aspect, an embodiment of the present application provides an access switching method, which can be applied to a terminal device, where the terminal device can refer to the terminal device itself, or a processor, module, chip, or chip system that implements the method in the terminal device. In the method, when the first condition is met, the terminal device sends sixth information, and the sixth information is used to request an uplink authorization of the terminal device. The first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, the first network device is the target network device to be accessed and switched by the terminal device, and the second network device is the network device currently providing services for the terminal device. The terminal device receives seventh information, and the seventh information is used to indicate the first uplink authorization configured by the first network device for the terminal device. When the second condition is met, the terminal device sends uplink data to the first network device according to the first uplink authorization to access the first network device, and the second condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, and the second threshold is greater than the first threshold; or, when the terminal device receives a cell switching command from the second network device, it sends uplink data to the first network device according to the first uplink authorization to access the first network device.

[0035] In the embodiment of the present application, the terminal device obtains the first uplink authorization configured by the first network device for the terminal device through the sixth information and the seventh information before the second condition is met or before the cell switching command from the second network device is received. Thus, when the second condition is met or when the cell switching command from the second network device is received, the terminal device can directly send uplink data to the first network device according to the obtained first uplink authorization to access the first network device, which can reduce the delay when the terminal device switches to the first network device.

[0036] In an optional implementation, before the terminal device sends uplink data to the first network device according to the first uplink authorization, it also receives a first indication, the first indication being used to indicate that the first network device has activated the first uplink authorization. That is, the terminal device can learn that the first uplink authorization has been activated by the first network device through the received first indication.

[0037] In an optional implementation, before the terminal device sends uplink data to the first network device according to the first uplink authorization, the terminal device receives the first threshold and the second threshold corresponding to the first network device, or receives the first threshold corresponding to the first network device.

[0038] In a fifth aspect, an embodiment of the present application also provides an access switching method, which can be applied to a third network device, where the third network device can refer to the third network device itself, or a processor, module, chip, or chip system that implements the method in the third network device. In the method, the third network device receives the sixth information and sends the sixth information to the first network device, the sixth information is used to request an uplink authorization of the terminal device, and the sixth information is sent by the terminal device when the first condition is met, the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, the first network device is the target network device to be accessed and switched by the terminal device, and the second network device is the network device currently providing services for the terminal device. The third network device receives the seventh information from the first network device and sends the seventh information, the seventh information is used to indicate the first uplink authorization configured by the first network device for the terminal device.

[0039] In an embodiment of the present application, when the third network device receives the sixth information for requesting the uplink authorization of the terminal device, it sends the sixth information to the first network device to request the first network device to configure the uplink authorization for the terminal device. When the third network device receives the first uplink authorization from the first network device indicating the configuration for the terminal device, it sends the seventh information so that the terminal device obtains the first uplink authorization. Among them, the sixth information received by the third network device is sent by the terminal device when the first condition is met, and the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, so that the terminal device obtains the first uplink authorization before determining to switch to the first network device, which is conducive to reducing the delay of the terminal device switching to the first network device.

[0040] In an optional implementation manner, the third network device sends the first threshold and the second threshold corresponding to the first network device, the second threshold is greater than the first threshold; or sends the first threshold corresponding to the first network device.

[0041] In the sixth aspect, the embodiment of the present application also provides an access switching method, which can be applied to a first network device, where the first network device can refer to the first network device itself, or a processor, module, chip, or chip system that implements the method in the first network device. In the method, the first network device receives sixth information from the third network device, the sixth information is used to request an uplink authorization of the terminal device, and the sixth information is sent by the terminal device to the third network device when the first condition is met. The first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold. The first network device is the target network device to be accessed and switched by the terminal device, and the second network device is the network device currently providing services for the terminal device. The first network device sends seventh information to the third network device, and the seventh information is used to indicate the first uplink authorization configured by the first network device for the terminal device. The first network device receives uplink data from the terminal device according to the first uplink authorization.

[0042] In the embodiment of the present application, the first network device receives the sixth information for requesting the uplink authorization of the terminal device, thereby configuring the first uplink authorization for the terminal device, and indicating the first uplink authorization through the seventh information. The sixth information is sent by the terminal device to the third network device when the first condition is met, so that the terminal device obtains the first uplink authorization before determining to switch to the first network device, which is conducive to reducing the delay of the terminal device switching to the first network device.

[0043] In an optional implementation, before receiving uplink data from the terminal device according to the first uplink authorization, the first network device also sends a first indication when a third condition is satisfied, and the first indication is used to indicate that the first network device has activated the first uplink authorization. The third condition is: the distance between the terminal device and the first network device is less than or equal to a first preset value, and / or the distance between the terminal device and the second network device is greater than a second preset value.

[0044] That is, when the third condition is met, the first network device determines that the terminal device will switch to the first network device, thereby activating the first uplink authorization configured for the terminal device, and notifies through the first indication that the first uplink authorization has been activated.

[0045] In the seventh aspect, the embodiments of the present application also provide a communication device. The communication device has the function of implementing some or all of the functions of the terminal device described in the first aspect or the fourth aspect above, or implementing some or all of the functions of the third network device described in the second aspect or the fifth aspect above, or implementing some or all of the functions of the first network device described in the third aspect or the sixth aspect above. For example, the functions of the communication device may have the functions of some or all of the embodiments of the terminal device described in the first aspect of the embodiments of the present application, or may have the functions of implementing any one of the embodiments of the present application separately. The functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the above functions.

[0046] In a possible design, the structure of the communication device may include a processing unit and a communication unit, and the processing unit is configured to support the communication device to perform the corresponding functions in the above method. The communication unit is used to support communication between the communication device and other communication devices. The communication device may also include a storage unit, which is used to couple with the processing unit and the communication unit, and store the necessary program instructions and data of the communication device.

[0047] In one implementation, the communication device includes: a processing unit and a communication unit;

[0048] The communication unit is used to receive first information, where the first information is used to indicate confirmation information that the first network device configures an uplink authorization for the terminal device, and the first network device is the destination network device to which the terminal device is to access and switch; the processing unit is used to determine, based on the first information, a first uplink authorization configured by the first network device for the terminal device, where the first uplink authorization includes a first time domain resource, and the first time domain resource is within a first time period, and the first time period is a time period for the terminal device to perform a switch to the first network device; the processing unit is also used to switch to the first network device based on the first uplink authorization.

[0049] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the first aspect mentioned above and will not be described in detail here.

[0050] In another embodiment, the communication device includes: a processing unit and a communication unit, wherein the processing unit is used to process the signal / signaling;

[0051] The communication unit is used to send fifth information to the first network device, the fifth information is used to request the first network device to configure an uplink authorization for the terminal device, the fifth information includes information for indicating a first time period, the time domain resources in the uplink authorization are within the first time period, the first time period is the time period for the terminal device to perform switching to the first network device, and the first network device is the destination network device for the terminal device to access and switch; the communication unit is also used to receive first information from the first network device and send the first information, the first information is used to indicate confirmation information that the first network device configures the uplink authorization for the terminal device.

[0052] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the above-mentioned second aspect and will not be described in detail here.

[0053] In yet another embodiment, the communication device comprises: a processing unit and a communication unit;

[0054] The communication unit is used to receive fifth information from a third network device, the fifth information is used to request the first network device to configure an uplink authorization for the terminal device, the fifth information includes information for indicating a first time period, the time domain resources in the uplink authorization are within the first time period, the first time period is a time period for the terminal device to perform switching to the first network device, and the first network device is the target network device to be accessed and switched by the terminal device; the communication unit is also used to send first information to the third network device, the first information is used to indicate confirmation information that the first network device configures the uplink authorization for the terminal device; the processing unit is used to receive uplink data from the terminal device according to the first uplink authorization configured for the terminal device, the first uplink authorization includes a first time domain resource, and the first time domain resource is within the first time period.

[0055] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the third aspect mentioned above and will not be described in detail here.

[0056] In yet another embodiment, the communication device comprises: a processing unit and a communication unit, wherein the processing unit is configured to process the signal / signaling;

[0057] The communication unit is used to send sixth information when a first condition is met, and the sixth information is used to request an uplink authorization for the terminal device, the first condition being that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, the first network device is the target network device to be accessed and switched by the terminal device, and the second network device is the network device currently providing services for the terminal device; the communication unit is also used to receive seventh information, and the seventh information is used to indicate a first uplink authorization configured by the first network device for the terminal device; the communication unit is also used to send uplink data to the first network device according to the first uplink authorization to access the first network device when a second condition is met, and the second condition being that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, and the second threshold is greater than the first threshold; or, when a cell switching command is received from the second network device, send uplink data to the first network device according to the first uplink authorization to access the first network device.

[0058] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the fourth aspect mentioned above, and will not be described in detail here.

[0059] In yet another embodiment, the communication device comprises: a processing unit and a communication unit, wherein the processing unit is configured to process the signal / signaling;

[0060] The communication unit is used to receive sixth information and send the sixth information to the first network device, the sixth information is used to request an uplink authorization for the terminal device, the sixth information is sent by the terminal device when a first condition is met, the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, the first network device is the destination network device to be accessed and switched by the terminal device, and the second network device is the network device currently providing services for the terminal device; the communication unit is also used to receive seventh information from the first network device and send the seventh information, the seventh information is used to indicate the first uplink authorization configured by the first network device for the terminal device.

[0061] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the fifth aspect above, which will not be described in detail here.

[0062] In yet another embodiment, the communication device comprises: a processing unit and a communication unit;

[0063] The communication unit is used to receive sixth information from a third network device, the sixth information is used to request an uplink authorization for a terminal device, the sixth information is sent by the terminal device to the third network device when a first condition is met, the first condition being that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a first threshold, the first network device is a target network device to be accessed and switched by the terminal device, and the second network device is a network device currently providing services for the terminal device; the communication unit is also used to send seventh information to the third network device, the seventh information is used to indicate a first uplink authorization configured by the first network device for the terminal device; the processing unit is used to receive uplink data from the terminal device according to the first uplink authorization.

[0064] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the sixth aspect mentioned above and will not be described in detail here.

[0065] As an example, the communication unit may be a transceiver or a communication interface, the storage unit may be a memory, and the processing unit may be a processor.

[0066] In one embodiment, the communication device includes: a processor and a transceiver;

[0067] The transceiver is used to receive first information, where the first information is used to indicate confirmation information that the first network device configures an uplink authorization for the terminal device, and the first network device is the destination network device to which the terminal device is to access and switch; the processor is used to determine, based on the first information, a first uplink authorization configured by the first network device for the terminal device, where the first uplink authorization includes a first time domain resource, and the first time domain resource is within a first time period, and the first time period is a time period for the terminal device to perform a switch to the first network device; the processor is also used to switch to the first network device based on the first uplink authorization.

[0068] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the first aspect mentioned above and will not be described in detail here.

[0069] In another embodiment, the communication device includes: a processor and a transceiver, wherein the processor is used to process the signal / signaling;

[0070] The transceiver is used to send fifth information to the first network device, the fifth information is used to request the first network device to configure an uplink authorization for the terminal device, the fifth information includes information for indicating a first time period, the time domain resources in the uplink authorization are within the first time period, the first time period is the time period for the terminal device to perform switching to the first network device, and the first network device is the destination network device for the terminal device to access and switch; the transceiver is also used to receive first information from the first network device and send the first information, the first information is used to indicate confirmation information that the first network device configures the uplink authorization for the terminal device.

[0071] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the above-mentioned second aspect and will not be described in detail here.

[0072] In yet another embodiment, the communication device comprises: a processor and a transceiver;

[0073] The transceiver is used to receive fifth information from a third network device, the fifth information is used to request the first network device to configure an uplink authorization for the terminal device, the fifth information includes information for indicating a first time period, the time domain resources in the uplink authorization are located within the first time period, the first time period is a time period for the terminal device to perform switching to the first network device, and the first network device is the target network device to be accessed and switched by the terminal device; the transceiver is also used to send first information to the third network device, the first information is used to indicate confirmation information that the first network device configures the uplink authorization for the terminal device; the processor is used to receive uplink data from the terminal device according to the first uplink authorization configured for the terminal device, the first uplink authorization includes a first time domain resource, and the first time domain resource is located within the first time period.

[0074] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the third aspect mentioned above and will not be described in detail here.

[0075] In yet another embodiment, the communication device comprises: a processor and a transceiver, the processor being configured to process the signal / signaling;

[0076] The transceiver is used to send sixth information when a first condition is met, and the sixth information is used to request an uplink authorization for the terminal device, the first condition being that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, the first network device is the target network device to be accessed and switched by the terminal device, and the second network device is the network device currently providing services for the terminal device; the transceiver is also used to receive seventh information, and the seventh information is used to indicate a first uplink authorization configured by the first network device for the terminal device; the transceiver is also used to send uplink data to the first network device according to the first uplink authorization to access the first network device when a second condition is met, and the second condition being that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, and the second threshold is greater than the first threshold; or, when a cell switching command is received from the second network device, send uplink data to the first network device according to the first uplink authorization to access the first network device.

[0077] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the fourth aspect mentioned above, and will not be described in detail here.

[0078] In yet another embodiment, the communication device comprises: a processor and a transceiver, the processor being configured to process the signal / signaling;

[0079] The transceiver is used to receive sixth information and send the sixth information to the first network device, the sixth information being used to request an uplink authorization for the terminal device, the sixth information being sent by the terminal device when a first condition is met, the first condition being that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a first threshold, the first network device being the destination network device to be accessed and switched by the terminal device, and the second network device being the network device currently providing services for the terminal device; the transceiver is also used to receive seventh information from the first network device and send the seventh information, the seventh information being used to indicate a first uplink authorization configured by the first network device for the terminal device.

[0080] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the fifth aspect above, which will not be described in detail here.

[0081] In yet another embodiment, the communication device comprises: a processor and a transceiver;

[0082] The transceiver is used to receive sixth information from a third network device, the sixth information is used to request an uplink authorization for a terminal device, the sixth information is sent by the terminal device to the third network device when a first condition is met, the first condition being that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a first threshold, the first network device is a target network device to be accessed and switched by the terminal device, and the second network device is a network device currently providing services for the terminal device; the transceiver is also used to send seventh information to the third network device, the seventh information is used to indicate a first uplink authorization configured by the first network device for the terminal device; the processor is used to receive uplink data from the terminal device according to the first uplink authorization.

[0083] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the sixth aspect mentioned above and will not be described in detail here.

[0084] In another embodiment, the communication device is a chip or a chip system. The processing unit may also be embodied as a processing circuit or a logic circuit; the communication unit may be an input / output interface, an interface circuit, an output circuit, an input circuit, a pin or a related circuit on the chip or the chip system.

[0085] During the implementation process, the processor can be used to perform, for example, but not limited to, baseband related processing, and the transceiver can be used to perform, for example, but not limited to, radio frequency transceiver. The above-mentioned devices can be respectively arranged on chips independent of each other, or at least partially or completely arranged on the same chip. For example, the processor can be further divided into an analog baseband processor and a digital baseband processor. Among them, the analog baseband processor can be integrated with the transceiver on the same chip, and the digital baseband processor can be arranged on an independent chip. With the continuous development of integrated circuit technology, more and more devices can be integrated on the same chip. For example, a digital baseband processor can be integrated with a variety of application processors (such as but not limited to a graphics processor, a multimedia processor, etc.) on the same chip. Such a chip can be called a system on a chip (system on a chip, SoC). Whether each device is independently arranged on different chips or integrated on one or more chips often depends on the needs of product design. The embodiment of the present application does not limit the implementation form of the above-mentioned devices.

[0086] In an eighth aspect, an embodiment of the present application further provides a processor for executing the above-mentioned various methods. In the process of executing these methods, the process of sending the above-mentioned information and receiving the above-mentioned information in the above-mentioned method can be understood as the process of outputting the above-mentioned information by the processor, and the process of receiving the above-mentioned information input by the processor. When outputting the above-mentioned information, the processor outputs the above-mentioned information to the transceiver so that it can be transmitted by the transceiver. After the above-mentioned information is output by the processor, it may also need to be processed in other ways before it reaches the transceiver. Similarly, when the processor receives the above-mentioned information input, the transceiver receives the above-mentioned information and inputs it into the processor. Furthermore, after the transceiver receives the above-mentioned information, the above-mentioned information may need to be processed in other ways before it is input into the processor.

[0087] For the sending and receiving operations involved in the processor, unless otherwise specified, or unless they conflict with their actual function or internal logic in the relevant description, they can be more generally understood as processor output, reception, input and other operations, rather than sending and receiving operations performed directly by the RF circuit and antenna.

[0088] In the implementation process, the processor may be a processor specifically used to execute these methods, or a processor that executes computer instructions in a memory to execute these methods, such as a general-purpose processor. The memory may be a non-transitory memory, such as a read-only memory (ROM), which may be integrated with the processor on the same chip or may be separately arranged on different chips. The embodiment of the present application does not limit the type of memory and the arrangement of the memory and the processor.

[0089] In a ninth aspect, an embodiment of the present application further provides a communication system, which includes a terminal device, a first network device, a second network device, and a third network device. In another possible design, the system may also include other devices that interact with the terminal device, the first network device, the second network device, and the third network device.

[0090] In a tenth aspect, an embodiment of the present application provides a computer-readable storage medium for storing instructions, which, when executed by a computer, implements the method described in any one of the first to sixth aspects above.

[0091] In the eleventh aspect, an embodiment of the present application further provides a computer program product comprising instructions, which, when executed on a computer, implements the method described in any one of the first to sixth aspects above.

[0092] In the twelfth aspect, an embodiment of the present application provides a chip system, which includes a processor and an interface, wherein the interface is used to obtain a program or instruction, and the processor is used to call the program or instruction to implement or support the terminal device to implement the functions involved in the first aspect or the fourth aspect, or to implement or support the third network device to implement the functions involved in the second aspect or the fifth aspect, or to implement or support the first network device to implement the functions involved in the third aspect or the sixth aspect. For example, determine or process at least one of the data and information involved in the above method. In one possible design, the chip system also includes a memory, which is used to store program instructions and data necessary for the terminal. The chip system can be composed of chips, and can also include chips and other discrete devices.

[0093] In the thirteenth aspect, an embodiment of the present application provides a communication device, comprising a processor for executing a computer program or executable instructions stored in a memory, so that when the computer program or executable instructions are executed, the device executes the methods in each possible implementation of the first to sixth aspects.

[0094] In one possible implementation, the processor and the memory are integrated together; in another possible implementation, the memory is located outside the communication device.

[0095] The beneficial effects of the seventh to thirteenth aspects can refer to the beneficial effects of the first to sixth aspects, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0096] Figure 1 It is a schematic diagram of the architecture of a non-terrestrial network (NTN);

[0097] Figure 2 This is another schematic diagram of the NTN network architecture;

[0098] Figure 3 This is another schematic diagram of the NTN network architecture;

[0099] Figure 4 This is another schematic diagram of the NTN network architecture;

[0100] Figure 5 It is a schematic diagram of a process of layer 1 / layer 2 triggered mobility (LTM);

[0101] Figure 6 is an interactive schematic diagram of an access switching method provided in an embodiment of the present application;

[0102] Figure 7is an interactive schematic diagram of another access switching method provided in an embodiment of the present application;

[0103] Figure 8 This is an interactive schematic diagram of another access switching method provided in an embodiment of the present application;

[0104] Fig. 9 This is an interactive schematic diagram of another access switching method provided in an embodiment of the present application;

[0105] Fig.10 This is an interactive schematic diagram of another access switching method provided in an embodiment of the present application;

[0106] Fig.11 This is an interactive schematic diagram of another access switching method provided in an embodiment of the present application;

[0107] Fig.12 This is an interactive schematic diagram of another access switching method provided in an embodiment of the present application;

[0108] Fig.13 is a structural diagram of a communication device provided in an embodiment of the present application;

[0109] Fig.14 It is a structural diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0110] The technical solutions in the embodiments of the present application are clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0111] In order to better understand the access switching method disclosed in the embodiment of the present application, a system to which the embodiment of the present application is applicable is described.

[0112] The embodiments of the present application can be applied to the fourth generation (4G) mobile communication system, the fifth generation (5G) mobile communication system, the non-terrestrial network NTN communication system, vehicle to everything (V2X), long term evolution-vehicle (LTE-V), vehicle to vehicle (V2V), machine type communications (MTC), Internet of Things (IoT), long term evolution-machine to machine (LTE-machine to machine, LTE-M), machine to machine (machine to machine, M2M), or future mobile communication systems.

[0113] In the embodiment of the present application, the network device refers to the access device that the terminal device accesses to the mobile communication system in a wireless manner, for example, including access network (AN) equipment, such as a base station. The network device may also refer to a device that communicates with the terminal device over the air interface. The network device may include an evolved Node B (also referred to as eNB or e-NodeB) in a long term evolution (LTE) system or an advanced long term evolution (LTE-A); or, the network device may also include a next generation node B (gNB) in a 5G new radio (NR) system; or, the network device may also include an access node in a wireless fidelity (Wi-Fi) system, etc.; or, the network device may be a relay station, a vehicle-mounted device, and a future evolved public land mobile network (PLMN) device, a device-to-device (D2D) network, a device in an M2M network, a device in an IoT network, or a network device in a public land mobile network (PLMN). The embodiments of the present application do not limit the specific technology and specific device form adopted by the network device.

[0114] In the embodiment of the present application, the communication device for realizing the function of the network device may be a network device, or may be a device capable of supporting the network device to realize the function, such as a chip system, which may be installed in the network device. In the technical solution provided in the embodiment of the present application, the technical solution provided in the embodiment of the present application is described by taking the device for realizing the function of the network device as an example that the network device is used as the device.

[0115] In the embodiment of the present application, the access network device may be a server, etc. For example, the network device in the vehicle V2X technology may be a road side unit (RSU). The following describes the access network device taking a base station as an example. The base station can communicate with the terminal device, or communicate with the terminal device through a relay station. The terminal device can communicate with multiple base stations in different access technologies.

[0116] The base station in the embodiment of the present application may include a centralized unit (CU) and a distributed unit (DU), and multiple DUs may be centrally controlled by one CU. CU and DU may be divided according to the protocol layer functions of the wireless network they possess, for example, the functions of the packet data convergence protocol (PDCP) layer and the protocol layers above are set in the CU, and the functions of the protocol layers below the PDCP, such as the radio link control (RLC) layer and the medium access control (MAC) layer, are set in the DU. It should be noted that this division of the protocol layer is only an example, and it can also be divided in other protocol layers. The radio frequency device can be pulled away and not placed in the DU, or it can be integrated in the DU, or part of it can be pulled away and part of it can be integrated in the DU, and the embodiment of the present application does not impose any restrictions. In addition, in some embodiments, the control plane (CP) and the user plane (UP) of the CU can also be separated and divided into different entities for implementation, namely the control plane CU entity (CU-CP entity) and the user plane CU entity (CU-UP entity). In this 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 this network architecture, the CU is divided into a network device on the radio access network (RAN) side. In addition, the CU can also be divided as a network device on the core network (CN) side, and this application does not limit this.

[0117] In the embodiment of the present application, the core network device is used to implement functions such as mobility management, data processing, session management, policy and billing. The names of the devices that implement the core network functions in systems with different access technologies may be different, and the embodiment of the present application does not limit this. Taking the 5G system as an example, the core network equipment includes: access and mobility management function (AMF), session management function (SMF), policy control function (PCF) or user plane function (UPF), etc.

[0118] In the embodiment of the present application, the terminal device is a device with wireless transceiver function, which can send signals to the network device or receive signals from the network device. The terminal device may include user equipment (UE), sometimes also referred to as terminal, access station, UE station, remote station, wireless communication device, or user device, etc. The terminal device is used to connect people, objects, machines, etc., and can be widely used in various scenarios, such as but not limited to the following scenarios: cellular communication, D2D, V2X, M2M / MTC, IoT, virtual reality (VR), augmented reality (AR), industrial control, self driving, remote medical, smart grid, smart furniture, smart office, smart wear, smart transportation, smart city, drone, robot and other scenarios of terminal devices. For example, the terminal device can be a mobile phone, a tablet computer, a computer with wireless transceiver function, a VR terminal, an AR terminal, a wireless terminal in industrial control, a wireless terminal in unmanned driving, a smart speaker in an IoT network, a wireless terminal device in telemedicine, a wireless terminal device in a smart grid, a wireless terminal device in transportation safety, a wireless terminal device in a smart city, or a wireless terminal device in a smart home, etc. As an example and not a limitation, in the embodiments of the present application, the terminal device can also be a wearable device. Wearable devices can also be called wearable smart devices or smart wearable devices, etc., which are a general term for wearable devices that are intelligently designed and developed using wearable technology for daily wear, such as glasses, gloves, watches, clothing and shoes. The various terminal devices introduced above, if located on a vehicle (for example, placed in a vehicle or installed in a vehicle), can be considered as vehicle-mounted terminal devices, and vehicle-mounted terminal devices are also called on-board units (OBU). The terminal device of the present application may also be a vehicle-mounted module, vehicle-mounted module, vehicle-mounted component, vehicle-mounted chip or vehicle-mounted unit that is built into the vehicle as one or more components or units. The vehicle can implement the method of the present application through the built-in vehicle-mounted module, vehicle-mounted module, vehicle-mounted component, vehicle-mounted chip or vehicle-mounted unit.

[0119] As a possible application scenario of an embodiment of the present application, the NTN system may include a satellite system. According to the satellite altitude, that is, the satellite orbit altitude, the satellite system is divided into high elliptical orbit (HEO) satellites, geosynchronous orbit (GEO) satellites, medium earth orbit (MEO) satellites and low-earth orbit (LEO) satellites. In addition, the NTN system may also include aerial network equipment such as a high altitude platform station (HAPS) communication system, and the aerial network equipment involved in this application is not limited to the above examples.

[0120] See also Figure 1 , Figure 1 Figure 1 is a schematic diagram of the architecture of an NTN network. Figure 1 As shown, the NTN network includes network equipment 1, network equipment 2, ground base stations, ground core network, data network and terminal equipment. Among them, network equipment 1 can be a satellite, for example, a HEO satellite, or a GEO satellite, or a MEO satellite, or a LEO satellite, or a HAPS, etc., which is not limited here. Network equipment 2 can be a gateway (also called a ground station, earth station, information gateway, gateway station) (gateway), which can be used to connect network equipment 1 and base stations. One or more network devices 1 can be connected to one or more ground base stations through one or more network devices 2, which is not limited here. Figure 1 In the example, the communication mode of network device 1 is transparent mode, that is, network device 1 acts as an analog RF repeater to achieve wireless frequency conversion and amplification, and can transparently transmit or copy the signal between the ground base station and the terminal device. For example, the signal sent by the terminal device can be transparently transmitted through network device 1, forwarded by network device 2, and enter the ground base station.

[0121] The present application embodiment does not limit the communication mode of the network device 1. For example, the communication mode of the network device 1 may also be a regenerative mode. Figure 2 , Figure 2 This is a schematic diagram of another NTN network architecture. Figure 2 In the embodiment, the communication mode of network device 1 is the regeneration mode, that is, network device 1 can be used as a base station for wireless communication to regenerate signals received from the ground, and can understand and process these signals. For example, network device 1 can be a base station carried on an artificial earth satellite or a high-altitude aircraft, for example, the base station can be an evolved base station (eNB) or a 5G base station (gNB). Network device 2 can forward signaling between network device 1 (i.e., base station) and the core network.

[0122] It should be noted that Figure 2 Only one network device 1 and one network device 2 are shown. In actual use, the architecture of multiple network devices 1 and / or multiple network devices 2 can be adopted as needed. Each network device 1 can provide services to one or more terminal devices, each network device 2 can correspond to one or more network devices 1, and each network device 1 can correspond to one or more network devices 2, which is not specifically limited in the embodiment of the present application.

[0123] See also Figure 3 , Figure 3 FIG. 1 is another schematic diagram of the NTN network architecture. Figure 3 As shown, the NTN network includes two network devices 1 and two network devices 2 as an example. The communication mode of the two network devices 1 is a regeneration mode, that is, the two network devices 1 can be used as base stations for wireless communication. Figure 2 The difference of the NTN network shown is that there is an inter-satellite link (ISL) between the two network devices 1. In other words, Figure 3 In the NTN network architecture shown, different network devices 1 can communicate with each other and can also be connected to the same ground core network.

[0124] As an example, the network device 1 can also be used as a DU of a base station, separated from the CU of a ground base station, to form a CU-DU distributed architecture. Figure 4 , Figure 4 FIG. 4 is a schematic diagram of another NTN network architecture. Figure 4 The NTN network shown is Figure 1 The difference of the NTN network shown is that the network device 1 acts as the DU of the base station, which can understand, process and regenerate the signal from the ground instead of just transparently transmitting or copying it, while the ground base station only acts as a CU. Figure 4 In the NTN network architecture shown, the service link between the terminal device and the network device 1 can transmit the NR-Uu wireless interface signal, and the feeder link between the network device 1 and the network device 2 transmits the satellite radio interface (SRI) signal. On top of the SRI signal, the F1 interface signal between the DU and the CU can be transmitted.

[0125] It should be noted that the embodiments of the present application are based on Figures 1 to 4 The NTN network shown in the figure is taken as an example, but is not limited to this scenario. Figures 1 to 4 The NTN network shown is not limited to Figures 1 to 4 The NTN network.

[0126] The embodiment of the present application is applicable to the scenario of intra-CU inter-DU, that is, applicable to a scenario of a CU and multiple DUs controlled by the CU, wherein the CU may be a ground base station in an NTN network, and the multiple DUs may be multiple satellites in an NTN network device.

[0127] Optionally, the embodiments of the present application may also be applicable to inter-CU scenarios, that is, to scenarios where multiple DUs are present, and each of the multiple DUs is connected to a CU. When the embodiments of the present application are applicable to inter-CU scenarios, the interaction between the first network device and the second network device is performed through the CU connected to the first network device and the CU connected to the second network device. For example, the first network device sends the first information, including: the first network device sends the first information to the CU connected to the first network device, the CU connected to the first network device sends the first information to the CU connected to the second network device, the CU connected to the second network device sends the first information to the second network device, and the second network device sends the first information to the terminal device.

[0128] In the embodiment of the present application, the first network device is the target network device to be accessed and switched by the terminal device, the second network device is the network device currently providing services for the terminal device, and the third network device is a network device used to control the first network device and the second network device. That is to say, the terminal device will switch from the second network device to the first network device, and the third network device is used to control the first network device and the second network device. When the embodiment of the present application is applied to the intra-CU inter-DU scenario in the NTN network, the first network device is the target DU to be accessed and switched by the terminal device, that is, the DU deployed on the target satellite to be accessed and switched by the terminal device; the second network device is the DU currently providing services for the terminal device, that is, the DU deployed on the satellite currently providing services for the terminal device; the third network device is a CU, which is located on the ground, that is, the third network device is a ground base station.

[0129] In the embodiment of the present application, CU and DU may be one product or two separate products.

[0130] Optionally, the embodiments of the present application may also be applied to intra-CU inter-DU scenarios in a terrestrial network.

[0131] It should be noted that the embodiment of the present application can be applied not only to handover between DUs, but also to cell handover. When the embodiment of the present application is applied to cell handover, the second network device can execute some of the steps that the third network device needs to execute.

[0132] The embodiments disclosed in this application will present various aspects, embodiments or features of the application around a system including multiple devices, components, modules, etc. It should be understood and appreciated that each system may include additional devices, components, modules, etc., and / or may not include all devices, components, modules, etc. discussed in conjunction with the drawings. In addition, combinations of these schemes may also be used.

[0133] The following describes the concepts involved in the embodiments of the present application:

[0134] 1.LTM.

[0135] LTM is the process in which the base station uses the media access control-control element (MAC CE) to change the service cell of the terminal device through a cell switch command (CSC) when the base station receives an L1 measurement report from the terminal device. The base station prepares and provides the terminal device with the configuration of the LTM candidate cell through radio resource control (RRC) signaling in advance. The base station selects the target cell from the LTM candidate cell configuration based on the L1 measurement report, and triggers the terminal device to switch to the target cell through the cell switch command. The base station can add, modify and release the LTM candidate cell configuration through RRC signaling.

[0136] Continuous LTM between LTM candidate cell configurations (i.e., after LTM is triggered, the terminal device does not release other LTM candidate cell configurations) can be performed without the need for RRC reconfiguration. LTM supports mobility between gNB-DUs within a gNB-DU and between gNB-DUs within a gNB-CU. LTM also supports inter-frequency mobility, including mobility to inter-frequency cells that are not the current serving cell. Continuous LTM is performed by repeating the steps of early synchronization, LTM execution, and completion with LMT, and the LTM candidate cell configuration is not released after each LTM is completed. Optionally, in satellite communication scenarios, the terminal device can delete the LTM candidate cell configuration after each LTM is completed.

[0137] See also Figure 5 , Figure 5 This is a schematic diagram of the LTM process. Figure 5 As shown, the process of executing LTM by the terminal device includes but is not limited to the following steps:

[0138] S501. The terminal device sends a measurement report 1 to the network device. Correspondingly, the network device receives the measurement report 1 from the terminal device. The terminal device is in an RRC connected state, and the measurement report 1 is a layer 3 (L3) measurement report.

[0139] S502. The network device sends an RRC reconfiguration message to the terminal device, wherein the RRC reconfiguration message includes LTM candidate cell configurations of one or more candidate cells. Correspondingly, the terminal device receives the RRC reconfiguration message from the network device.

[0140] Before the network device sends an RRC reconfiguration message to the terminal device, it determines to use LTM based on the measurement report 1 reported by the terminal device and starts candidate cell preparation of the terminal device.

[0141] S503. The terminal device sends an RRC reconfiguration complete message to the network device. Correspondingly, the network device receives the RRC reconfiguration complete message from the terminal device.

[0142] It is understandable that after receiving the RRC reconfiguration message from the network device, the terminal device saves the LTM candidate cell configuration and sends an RRC reconfiguration completion message to the network device, that is, a message indicating that the RRC reconfiguration configuration is completed.

[0143] S5041. The terminal device performs downlink synchronization with the candidate cell.

[0144] S5042. The terminal device performs uplink synchronization with the candidate cell.

[0145] It is understandable that the terminal device can synchronize with the candidate cell and obtain the timing advance (TA) corresponding to the candidate cell before receiving the CSC. The terminal device can perform downlink synchronization with the candidate cell through the synchronization signal and physical broadcast channel block (SSB) before receiving the cell switching command. In addition, the terminal device at least supports the random access channel (RACH) initiated by the physical downlink control channel (PDCCH) order to obtain the TA value of the candidate cell before the LTM cell switching command CSC, where the PDCCH order can be triggered by the source cell of the terminal device. In addition, the random access channel can also be referred to as random access.

[0146] S505. The terminal device sends a measurement report 2 to the network device. Correspondingly, the network device receives the measurement report 2 from the terminal device.

[0147] It can be understood that the terminal device measures the configured candidate cell, obtains measurement report 2, and sends measurement report 2 to the network device, and measurement report 2 is an L1 measurement report.

[0148] Currently, when the terminal device sends measurement report 2, it supports periodic reporting in the physical uplink control channel (PUCCH), semi-static reporting on the PUCCH / physical downlink shared channel (PUSCH), and non-periodic reporting on the PUSCH.

[0149] S506. The network device sends a cell switching command to the terminal device. Correspondingly, the terminal device receives the cell switching command from the network device.

[0150] It is understandable that when the network device determines that the terminal device needs to perform cell switching to the target cell based on measurement report 2, it sends a cell switching command to the terminal device to trigger the terminal device to switch to the target cell. The cell switching command includes a candidate configuration index of the target cell, and the cell switching command is carried in the MAC CE signaling.

[0151] S507. The terminal device initiates random access to the target cell.

[0152] After receiving the cell switching command from the network device, the terminal device initiates random access to the target cell, that is, performs a random access process to the target cell to access the target cell.

[0153] S508. The terminal device completes switching to the target cell.

[0154] like Figure 5 As shown, Figure 5 In the LTM process shown, S501 to S503 can be regarded as the preparation stage for the terminal device to execute LTM, S5041 and S5042 can be regarded as the synchronization stage between the terminal device and the candidate cell, S505 to S507 can be regarded as the stage for the terminal device to execute LTM, and S508 can be regarded as the completion stage for the terminal device to execute LTM.

[0155] Optionally, after the terminal device completes the switching with the target cell, the cell switching in the continuous LTM may be performed according to the measurement configuration in the RRC configuration message in S502 and in accordance with S504 to S508.

[0156] 2. Uplink grant (UL grant).

[0157] UL grant is a specific physical control channel information from the network side and is another name for the downlink control information (DCI) format. UL grant carries a variety of information, the most important of which is "resource allocation" and modulation and coding scheme (MCS). After the terminal device obtains UL grant, it can transmit data according to the UL grant, such as transmitting data according to the resources and MCS in the UL grant.

[0158] 3. Random access channel-less (RACH-less).

[0159] RACH-less means: if the terminal device can obtain the TA of the target cell and the initial UL grant of the target cell in advance through relevant mechanisms, the terminal device will omit the sending of Msg1 and Msg2 during the random access process to the target cell and can directly send Msg3 to the target cell.

[0160] In NTN communication, the TA of the target cell can usually be obtained in advance through ephemeris and other methods. Therefore, if the terminal device can obtain the initial UL grant of the target cell in advance, RACH-less handover can be performed. The terminal device performs RACH-less handover, which can reduce the handover delay to a certain extent.

[0161] 4. Conditional handover (CHO).

[0162] CHO means that after receiving the CHO configuration, the terminal device does not immediately perform the handover action, but continues to measure and evaluate the candidate cells, and when the handover conditions are met, selects the corresponding target cell to access. In the NTN scenario, the current CHO includes time-based CHO and location-based CHO.

[0163] Time-based CHO means that each candidate cell corresponds to a time period. When the terminal device switches to a candidate cell, CHO starts after entering the time period corresponding to the candidate cell. Location-based CHO means that when the distance between the terminal device and the reference position of the primary cell is greater than threshold 1, and the distance between the terminal device and the reference position corresponding to the candidate cell is less than threshold 2, CHO starts. In addition, CHO in the NTN scenario can also be combined with A3 / A4 / A5 events.

[0164] Compared with terrestrial communications, satellite communications have been widely used in aviation, energy and other fields due to their wide coverage, no geographical restrictions, and high reliability. At present, satellite communications, as an extremely important communication scenario in 5G communications, have been introduced by the 3rd Generation Partnership Project (3GPP) under the name of NTN. Satellite communications can provide communication services for areas that are not covered or insufficiently covered by terrestrial networks; they can also provide stable emergency communications in the event of natural disasters or large-scale events; they can also provide high-quality communication services for users on vehicles such as trains, ships and airplanes; and they can also provide specialized services for government and enterprise users to meet specific business needs.

[0165] In the terrestrial network, when the terminal device detects that the signal quality of the current cell has deteriorated or the quality of the adjacent cell has improved, the terminal device reports a signal quality measurement report to the currently connected network device. After receiving the measurement report, the network device selects a target cell for the terminal device and informs the terminal device. Thus, the terminal device performs a switch between the target cell and the current cell.

[0166] However, in non-terrestrial networks, the distance between satellites and the ground is relatively long, and the round-trip signal transmission time can usually reach several milliseconds or even tens of milliseconds. If the terminal device still uses the cell switching method in the terrestrial network to switch cells, it will cause a long switching delay. In addition, since the signal quality of the terminal device is usually poor when switching, the long switching delay may cause the terminal to fail to switch. Therefore, the current switching technology in the terrestrial network cannot be directly applied to the satellite network.

[0167] To reduce the switching delay of terminal devices in the NTN network, the terminal devices can perform RACH-less in LTM, that is, the terminal devices Figure 5 In the LTM process shown, the random access process of S507 is not performed, and the uplink data is directly sent to the target DU using the UL grant to access the target DU. In the NTN scenario, the TA of the target DU can be obtained in advance through the ephemeris information, and the acquisition methods of UL grant include configured grant and dynamic grant.

[0168] Among them, in the configuration authorization method, when the source DU sends the CSC, the UL grant is sent to the terminal device together. This method requires the source DU to send a UL grant request to the target DU before sending the CSC. However, in the scenario of switching between DUs within the same CU (i.e., intra-CU inter-DU), the source DU and the target DU communicate through F1AP signaling, that is, the information is from the source DU to the CU, and then from the CU to the target DU, and the delay is greater than 10ms, which will cause additional delays and increase the switching time.

[0169] For dynamic grant, in the scenario of switching between DUs within the same CU, UL grant can be provided by the target DU through PDCCH. In this method, the source DU is also required to notify the target DU, and the UE will switch to the target DU. If the source DU receives the L1 measurement report and then informs the target DU to send UL grant, this F1AP signaling interaction will also cause additional delays. In addition, the target DU also needs to wait for the PDCCH opportunity to send PDCCH.

[0170] In another way, the network device can configure ULgrant for all candidate DUs for the terminal device before the terminal device executes LTM, and send it to the terminal device through the RRC reconfiguration message. After receiving the cell switching command, the terminal device directly uses the ULgrant corresponding to the target DU to send uplink data to the target DU. However, in this scenario, all candidate DUs of the terminal device need to reserve resources in the ULgrant for the terminal device in advance. The reserved resources are large and cannot be used by other terminal devices, which will cause resource waste.

[0171] In another method, the terminal device can also use CHO and RACH-less in LTM. In this method, the target DU also needs to reserve the resources corresponding to ULgrant for the terminal device in advance. For example, in time-based CHO, the target DU needs to reserve the resources corresponding to ULgrant [t1, t2] for the terminal device, which cannot be used by other terminal devices and will also cause resource waste.

[0172] The embodiment of the present application proposes an access switching method 100. In the access switching method 100, the third network device requests the first network device to configure an uplink authorization for the terminal device through the fifth information. The first network device indicates the confirmation information of the first network device configuring the uplink authorization for the terminal device through the first information. The terminal device determines the first uplink authorization configured by the first network device for the terminal device according to the first information, and sends uplink data to the first network device according to the first uplink authorization to access the first network device. Among them, the fifth information includes information for indicating the first time period, the first time period is the time period in which the terminal device performs switching to the first network device, and the time domain resources in the uplink authorization are located within the first time period. Thus, the first time domain resources in the first uplink authorization configured for the terminal device by the first network device according to the first time period are located within the first time period, so that the first time domain resources occupy less time, that is, the time domain resources reserved in advance by the first network device for the terminal device are less, which can reduce resource waste.

[0173] The embodiment of the present application also proposes an access switching method 200. In the access switching method 200, when the first condition is met, the terminal device obtains the uplink authorization of the terminal device through the sixth information request, and the first condition is that the signal quality corresponding to the first network device is greater than the signal quality corresponding to the second network device by a first threshold. The first network device indicates the first uplink authorization configured by the first network device for the terminal device through the seventh information. Furthermore, when the second condition is met, or when the cell switching command from the second network device is received, the terminal device can send uplink data to the first network device according to the first uplink authorization to access the first network device, which can reduce the switching delay of the terminal device to the first network device. Among them, the second condition is that the signal quality corresponding to the first network device is greater than the signal quality corresponding to the second network device by a second threshold, and the second threshold is greater than the first threshold.

[0174] The embodiment of the present application also proposes an access switching method 300. In the access switching method 300, the third network device requests the first network device to configure a random access resource for the terminal device through the eighth information. The first network device indicates the first random access resource configured for the terminal device through the ninth information. Thus, before the terminal device receives the cell switching command from the second network device, it obtains the first random access resource configured for the terminal device by the first network device. Furthermore, when the terminal device receives the cell switching command from the second network device, it can directly initiate random access to the first network device based on the obtained first random access resource, which can reduce the switching delay of the terminal device to the first network device.

[0175] This embodiment of the application proposes an access switching method 100. Figure 61 is an interactive schematic diagram of the access switching method 100. The access switching method 100 is described from the perspective of the interaction between the terminal device, the first network device, the second network device and the third network device. The access switching method 100 includes but is not limited to the following steps:

[0176] S601. The third network device sends fifth information to the first network device, the fifth information is used to request the first network device to configure an uplink authorization for the terminal device, the fifth information includes information for indicating a first time period, the time domain resources in the uplink authorization are within the first time period, and the first time period is a time period in which the terminal device performs a handover to the first network device. Correspondingly, the first network device receives the fifth information from the third network device.

[0177] The first time period is a time period in which the terminal device performs handover to the first network device. The handover performed by the terminal device to the first network device may be a triggered handover LTM, or may be RACH-less. The embodiment of the present application does not limit the manner in which the terminal device performs handover to the first network device.

[0178] For example, when the handover performed by the terminal device to the first network device is LTM, the starting time of the first time period is the starting time of the terminal device performing LTM on the first network device, and the ending time is the ending time of the terminal device performing LTM on the first network device. The starting time of the terminal device performing LTM on the first network device is the time when the terminal device sends a layer 1 measurement report to the second network device, and the ending time of the terminal device performing LTM on the first network device is the time when the terminal device accesses the first network device, for example, the ending time is the time when the terminal device sends uplink data to the first network device, and for another example, the ending time is the time when the terminal device receives an acknowledgment (ACK) from the first network device, and the ACK is the reply of the first network device to the successful receipt of uplink data from the terminal device. In other words, the starting time of the first time period can be the time when the terminal device sends a layer 1 measurement report to the second network device, and the ending time can be the time when the terminal device accesses the first network device.

[0179] Optionally, the start time of the terminal device executing LTM for the first network device is the time when the terminal device sends the first uplink data to the first network device, and the end time of the terminal device executing LTM for the first network device is the end time when the terminal device sends the uplink data to the first network device. That is, the start time of the first time period is the time when the terminal device sends the first uplink data to the first network device, and the end time is the end time when the terminal device sends the uplink data to the first network device. Compared with the method in which the start time of the first time period is the time when the terminal device sends the layer 1 measurement report to the second network device, and the end time is the time when the terminal device sends the uplink data to the first network device, the first time period occupies fewer resources and can save resource overhead.

[0180] Optionally, if the first time period is [ton, toff], the first time period can also be updated to [ton+δ1, toff+δ2], that is, a time offset can be added to the first time period. This method can flexibly adjust the size of the first time period, thereby enabling the first network device to flexibly configure the time domain resources in the uplink authorization for the terminal device.

[0181] It is understandable that the first time period may be predicted by the third network device based on the location information of the terminal device and the ephemeris status of the first network device.

[0182] The first time period is used by the first network device to determine the uplink authorization of the terminal device, the time domain resources in the uplink authorization are within the first time period, and the first time period is the time period in which the terminal device performs a handover to the first network device. Then, when the first network device determines the time domain resources in the uplink authorization configured for the terminal device according to the first time period, the time domain resources reserved by the first network device for the terminal device occupy less time, which can reduce resource waste.

[0183] It is understandable that the fifth information includes information indicating the first time period, so that the first network device can obtain the first time period according to the fifth information. For example, the fifth information includes the first time period, so that the first network device can directly know the first time period through the fifth information.

[0184] The embodiment of the present application does not limit the form of the fifth information. For example, the fifth information may be a request message. For another example, the fifth information may be an instruction, and so on.

[0185] In an optional implementation, the third network device may send the fifth information by sending a user information setup request (UE CONTEXT SETUP REQUEST) to the first network device. The user information setup request is used to request the first network device to join the candidate cell for L1 / L2 switching. That is, the fifth information may be carried in the user information setup request, which can reduce signaling overhead.

[0186] It is understandable that the third network device sends the fifth information to the first network device to which the terminal device is to be switched, so as to request the first network device to configure the uplink authorization for the terminal device, which is beneficial for the terminal device to switch to the first network device according to the uplink authorization configured by the first network device for the terminal device when the terminal device needs to switch to the first network device, so as to reduce the switching delay. In addition, the fifth information includes information for indicating the first time period, which is beneficial for the first network device to configure the time domain resources in the uplink authorization for the terminal device according to the first time period, thereby reducing the time occupied by the time domain resources in the uplink authorization configured by the first network device for the terminal device, that is, reducing the waste of resources when the terminal device switches to the first network device.

[0187] Optionally, the fifth information is sent by the third network device to the first network device through the F1 interface.

[0188] S602. The first network device sends first information to the third network device, where the first information is used to instruct the first network device to configure confirmation information of uplink authorization for the terminal device. Correspondingly, the third network device receives the first information from the first network device.

[0189] It is understandable that after the first network device receives the fifth information from the third network device, it determines whether the uplink authorization can be configured for the terminal device, and when it is confirmed that the uplink authorization is configured for the terminal device, it sends the first information to the third network device to inform the third network device of the confirmation information that the first network device configures the uplink authorization for the terminal device.

[0190] The embodiment of the present application does not limit the form of the first information. For example, the first information may be a request response for feeding back the fifth information. For another example, the first information may be another indication corresponding to the fifth information, and so on.

[0191] In an optional implementation, when the fifth information is carried in the user information establishment request, the first network device may send the first information by sending a user information modification response (UE CONTEXT MODIFICATION RESPONSE) to the third network device. The user information modification response is a reply of the first network device to the user information establishment request. That is, the fifth information may be carried in the user information establishment request, and the first information may be carried in the user information modification response, which can reduce signaling overhead.

[0192] S603: The third network device sends the first information. Correspondingly, the terminal device receives the first information.

[0193] It is understandable that the third network device sends the first information to the second network device, and the second network device then sends the first information to the terminal device. Thus, the terminal device receives the first information.

[0194] Among them, the first information sent by the first network device to the third network device, the first information sent by the third network device to the second network device, and the first information sent by the second network device to the terminal device, any two or three of the three are the same or different in form, and the embodiments of the present application do not limit this. In addition, when other information in the embodiments of the present application is similar to the sending method of the first information, the specific form of the information is not limited.

[0195] For example, after receiving the first information from the first network device, the third network device processes the first information to obtain the processed first information #1, and then sends the processed first information #1 to the second network device, and the second network device then directly sends the first information #1 to the terminal device. In this manner, the first information sent by the third network device to the first network device is in a different form from the first information #1 sent by the third network device to the second network device, but the first information and the first information #1 are both used to indicate that the first network device has configured uplink authorization confirmation information for the terminal device.

[0196] Optionally, the first information sent by the third network device to the second network device and the first information sent by the second network device to the terminal device may be carried in the RRC reconfiguration information to reduce signaling overhead.

[0197] In an optional implementation, the fifth information is also used to request the acquisition of the receiving beam of the first network device. When the fifth information is also used to request the acquisition of the receiving beam of the first network device, the first information is also used to indicate the receiving beam of the first network device. This method is conducive to the terminal device obtaining the receiving beam of the first network device, and further conducive to the terminal device determining the transmission beam used to send uplink data to the first network device based on the receiving beam of the first network device, which is conducive to improving the success rate of the first network device receiving uplink data from the terminal device.

[0198] In another optional implementation, the fifth information is also used to request the acquisition of the transmission beam of the terminal device. When the fifth information is also used to request the acquisition of the transmission beam of the terminal device, the first information is also used to indicate the transmission beam of the terminal device, and the transmission beam of the terminal device is determined by the first network device according to the receiving beam of the first network device. This is conducive to the terminal device sending uplink data to the first network device according to the transmission beam indicated by the first information, and can improve the success rate of the first network device receiving uplink data from the terminal device.

[0199] S604. The terminal device determines, based on the first information, a first uplink authorization configured by the first network device for the terminal device, where the first uplink authorization includes a first time domain resource, and the first time domain resource is within a first time period.

[0200] After receiving the first information, the terminal device learns through the first information that the first network device confirms to configure the uplink authorization for the terminal device. Further, the terminal device determines the first uplink authorization configured by the first network device for the terminal device based on the first information.

[0201] It is understandable that the fifth information includes information for indicating the first time period, the first time period is used to determine the uplink authorization of the terminal device, and the time domain resources in the uplink authorization are located in the first time period. Thus, the first network device determines the first time domain resources in the uplink authorization based on the first time period, and the first time domain resources are located in the first time period. Optionally, the first network device may also determine the frequency domain resources in the uplink authorization based on the first time period.

[0202] Optionally, the first network device may also determine the content other than the first time domain resource in the uplink authorization based on other information other than the first time period, such as determining the MCS. That is, in addition to determining the uplink authorization of the terminal device based on the first time period, the first network device may also determine the uplink authorization of the terminal device based on information other than the first time period.

[0203] In an optional implementation, when the first network device confirms that an uplink authorization is configured for the terminal device, the first uplink authorization is configured for the terminal device, and the first uplink authorization configured for the terminal device is indicated by the first information, that is, the first information is also used to indicate the first uplink authorization configured for the terminal device by the first network device. In this manner, the terminal device can obtain the first uplink authorization through the first information.

[0204] In another optional implementation, when the first network device confirms that the uplink authorization is configured for the terminal device, the uplink authorization is not configured for the terminal device yet, and the first uplink authorization is configured for the terminal device at a first moment, and the first uplink authorization is indicated to the terminal device through a fourth message, and the first moment is later than or equal to the start moment of the first time period. That is, the first network device sends the fourth message at the first moment, and the fourth message is used to indicate the first uplink authorization. In this way, the terminal device determines that the first uplink authorization configured for the terminal device by the first network device, including: receiving the fourth message, the fourth message is used to indicate the first uplink authorization; according to the fourth message, determining the first uplink authorization configured for the terminal device by the first network device. That is, the terminal device can obtain the first uplink authorization through the received fourth message.

[0205] Optionally, the fourth information may be a PDCCH. That is, the first network device sends a PDCCH at a first moment later than or equal to the start moment of the first time period, and the PDCCH includes information for indicating a first uplink authorization. Accordingly, the terminal device receives the PDCCH through blind detection, and obtains from the PDCCH the first uplink authorization configured by the first network device for the terminal device.

[0206] The manner in which the first network device sends the first uplink authorization through the fourth information can be understood as: the first network device enables the terminal device to obtain the first uplink authorization through a dynamic grant.

[0207] It can be seen that the first time domain resource in the first uplink authorization configured by the first network device for the terminal device is located in the first time period, that is, the first time domain resource reserved by the first network device for the terminal device is located in the first time period, and the first time period is the time when the terminal device performs switching to the first network device. In this case, the first time domain resource reserved by the first network device for the terminal device occupies less time, which can reduce resource waste.

[0208] S605. The terminal device switches to the first network device according to the first uplink authorization.

[0209] It is understandable that the terminal device switches to the first network device according to the first uplink authorization, which means that the terminal device switches to the first network device according to the first time domain resource in the first uplink authorization, that is, sends uplink data to the first network device according to the first time domain resource in the first uplink authorization to switch to the first network device. Optionally, the first uplink authorization also includes frequency domain resources and MCS, so that the terminal device sends uplink data to the first network device according to the first time domain resources, frequency domain resources and MCS in the first uplink authorization to switch to the first network device.

[0210] The implementation manner in which the terminal device switches to the first network device according to the first uplink authorization includes but is not limited to the following implementation manners:

[0211] Implementation method a: the terminal device receives a cell switching command from the second network device, and sends uplink data to the first network device according to the first uplink authorization to access the first network device.

[0212] It is understandable that, before switching to the first network device based on the first uplink authorization, the terminal device reports a layer 1 measurement report to the second network device, and the layer 1 measurement report includes multiple measurement results obtained by the terminal device measuring the reference signal from the candidate network device. The second network device determines whether the terminal device needs to switch to a certain network device based on the received layer 1 measurement report. When the second network device determines that the terminal device needs to switch to the first network device, it sends a cell switching command to the terminal device, and the cell switching command includes the identifier of the first network device. It can be seen that the second network device can instruct the terminal device to switch to the first network device through the cell switching command.

[0213] Furthermore, when the terminal device receives a cell switching command from the second network device, and upon receiving the cell switching command from the second network device, it learns that it needs to switch to the first network device, it sends uplink data to the first network device according to the first uplink authorization configured for the terminal device by the first network device, that is, performs RACH-less to the first network device to access the first network device. Among them, the first time domain resource in the first uplink authorization used by the terminal device to send uplink data to the first network device is located in the first time period, and the first time period is the time period in which the terminal device performs switching to the first network device, so that the first time domain resource occupies less time, which can reduce the waste of resources when the terminal device switches to the first network device.

[0214] In an optional implementation, when the third condition is satisfied, the first network device sends a first indication, the first indication being used to indicate that the first network device has activated the first uplink authorization. Accordingly, before the terminal device switches to the first network device according to the first uplink authorization, or before sending uplink data to the first network device according to the first uplink authorization, the terminal device receives the first indication, and learns through the first indication that the first uplink authorization configured by the first network device for the terminal device has been activated.

[0215] Optionally, when the third condition is not met, the first network device does not send the first indication.

[0216] The third condition is that the current time is within the first time period; or the third condition is that the distance between the terminal device and the first network device is less than or equal to the first preset value, and / or the distance between the terminal device and the second network device is greater than the second preset value. For example, the third condition is: the distance between the terminal device and the satellite where the first network device is located is less than α1. For another example, the third condition is: the distance between the terminal device and the satellite where the second network device is located is greater than α2. For another example, the third condition is: the distance between the terminal device and the location where the first network device is located is less than α1, and the distance between the terminal device and the satellite where the second network device is located is greater than α2.

[0217] That is, when the current time is within the first time period, the first network device notifies the terminal device through the first indication that the first uplink authorization has been activated by the first network device. Alternatively, when the distance between the terminal device and the first network device is less than or equal to the first preset value, and / or the distance between the terminal device and the second network device is greater than the second preset value, the first network device notifies the terminal device through the first indication that the first uplink authorization has been activated by the first network device.

[0218] Alternatively, it can also be understood as: when the current time is within the first time period, the first network device activates the first uplink authorization configured for the terminal device, and informs the terminal device through a first indication that the first uplink authorization has been activated by the first network device; or, when the distance between the terminal device and the first network device is less than or equal to a first preset value, and / or the distance between the terminal device and the second network device is greater than a second preset value, the first network device activates the first uplink authorization configured for the terminal device, and informs the terminal device through a first indication that the first uplink authorization has been activated by the first network device.

[0219] When the current moment is within the first time period, it indicates that the terminal device enters the stage of switching to the first network device, and the terminal device will switch to the first network device, then the first network device determines to activate the first uplink authorization configured for the terminal device, so that the first uplink authorization can be used by the terminal device. When the distance between the terminal device and the first network device is less than or equal to the first preset value, and / or the distance between the terminal device and the second network device is greater than the second preset value, it indicates that the satellite where the first network device is located will provide services for the terminal device, that is, the terminal device will switch to the first network device, then the first network device activates the first uplink authorization configured for the terminal device, so that the first uplink authorization can be used by the terminal device.

[0220] Optionally, the terminal device also reports the location information of the terminal device to the third network device through the second network device, so that the third network device determines the distance between the terminal device and the second network device, and / or determines the distance between the terminal device and the first network device. Thus, the third network device can inform the first network device of the determined distance, so that the first network device determines whether to activate the first uplink authorization configured for the terminal device according to the distance between the terminal device and the second network device and / or the first network device.

[0221] Optionally, the third condition may also be: the elevation angle between the terminal device and the first network device is greater than a third preset value, and / or the elevation angle between the terminal device and the second network device is less than a fourth preset value. Among them, the elevation angle between the terminal device and the first network device can be understood as the elevation angle of the terminal device relative to the first network device. The elevation angle between the terminal device and the second network device is similar and will not be repeated. For example, the elevation angle between the terminal device and the satellite where the first network device is located is greater than θ1, and / or the elevation angle between the terminal device and the satellite where the second network device is located is less than θ2. That is to say, the first network device can also determine whether to activate the first uplink authorization based on the elevation angle between the terminal device and the first network device and / or the second network device.

[0222] Optionally, the third condition may also be: the depression angle between the terminal device and the first network device is less than a ninth preset value, and / or the depression angle between the terminal device and the second network device is greater than a tenth preset value. The depression angle between the terminal device and the first network device is the depression angle of the first network device relative to the terminal device. The depression angle between the terminal device and the second network device is similar and will not be described in detail.

[0223] Optionally, the third condition may also be: the remaining service time of the second network device to the terminal device is less than the fifth preset value. Optionally, the third condition may also be: the remaining coverage time of the satellite where the second network device is located to the terminal device is less than the sixth preset value. It can be seen that the first network device can also determine whether to activate the first uplink authorization based on the remaining service time of the second network device to the terminal device, or based on the remaining coverage time of the second network device to the terminal device. Among them, the remaining service time of the second network device to the terminal device, and the remaining coverage time of the second network device to the terminal device, can be determined by the first network device itself, or can be notified to the first network device after the third network device determines it. Optionally, the third condition may also be: the remaining service time of the first network device to the terminal device is less than the seventh preset value. Optionally, the third condition may also be: the remaining coverage time of the satellite where the first network device is located to the terminal device is less than the eighth preset value. Optionally, the third condition may also be: the remaining service time of the second network device to the terminal device is less than the fifth preset value, and the remaining service time of the first network device to the terminal device is less than the seventh preset value. Optionally, the third condition may also be: the remaining coverage time of the satellite where the second network device is located to the terminal device is less than a sixth preset value, and the remaining coverage time of the satellite where the first network device is located to the terminal device is less than an eighth preset value.

[0224] In addition, when the third condition is met, the first network device sends the first indication, which can be understood as: when the third condition is met, the first network device sends the first indication to the third network device, the third network device then sends the first indication to the second network device, and the second network device then sends the first indication to the terminal device. Thus, the terminal device receives the first indication, and learns through the first indication that the first network device has activated the first uplink authorization, and then receives the cell switching command from the second network device, and sends uplink data to the first network device according to the activated first uplink authorization, so as to access the first network device.

[0225] In another optional implementation, the terminal device may also determine that the first uplink authorization has been activated by the first network device without receiving the first indication. The terminal device may determine by itself whether the first uplink authorization has been activated by the first network device. Specifically, the terminal device determines that the first uplink authorization has been activated by the first network device when the current time is later than the first time period. Optionally, the terminal device determines that the first uplink authorization has been activated by the first network device when the above third condition is met. For example, the terminal device determines that the first uplink authorization has been activated by the first network device when the distance between the terminal device and the first network device is less than or equal to the first preset value, and / or the distance between the terminal device and the second network device is greater than the second preset value. Thus, when the terminal device receives the cell switching command from the second network device, it sends uplink data to the first network device according to the activated first uplink authorization. Optionally, when the above third condition is not met, the terminal device determines that the first uplink authorization has not been activated by the first network device.

[0226] Optionally, when the current time of the terminal device is later than the first time period, the third network device also informs the terminal device of the first time period in a manner in which the first uplink authorization has been activated by the first network device. For example, the third network device informs the terminal device of the first time period corresponding to the first network device through an RRC reconfiguration message.

[0227] It is understandable that in the manner in which the terminal device determines whether the first uplink authorization has been activated by the first network device, the first network device and the terminal device use the same manner to determine whether the first uplink authorization has been activated. Thus, the terminal device and the first network device can align whether the first uplink authorization has been activated. Furthermore, when the terminal device sends uplink data to the first network device according to the first uplink authorization, the first network device also receives uplink data from the terminal device according to the first uplink authorization.

[0228] Implementation method b: When a first condition is met, the terminal device sends second information, where the second information is used to request activation of a first uplink authorization configured by the first network device for the terminal device, and the first condition is that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a first threshold; the terminal device receives third information, where the third information is used to indicate that the first network device has activated the first uplink authorization; when the second condition is met, the terminal device sends uplink data to the first network device according to the first uplink authorization to access the first network device, and the second condition is that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a second threshold.

[0229] Among them, the second threshold is greater than the first threshold. The signal quality corresponding to the first network device can be understood as: the signal quality obtained by the terminal device measuring the reference signal received from the first network device; the signal quality corresponding to the second network device can be understood as: the signal quality obtained by the terminal device measuring the reference signal received from the second network device. Optionally, when the first network device is located in a neighboring cell of the terminal device and the second network device is located in a service cell of the terminal device, the signal quality corresponding to the first network device is the signal quality obtained by the terminal device measuring the signal of the neighboring cell, and the signal quality corresponding to the second network device is the signal quality obtained by the terminal device measuring the signal of the service cell.

[0230] In addition, the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, which can be regarded as the first A3 event; the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, which can be regarded as the second A3 event.

[0231] When the first A3 event is met, the terminal device determines that the terminal device may switch to the first network device, and thus requests the first network device to activate the first uplink authorization through the second information to obtain the usable first uplink authorization. After receiving the second information, the first network device activates the first uplink authorization and notifies through the third information that the first uplink authorization has been activated. Therefore, when the second A3 event is met, the terminal device determines that the terminal device needs to switch to the first network device, and then sends uplink data to the first network device according to the activated first uplink authorization to access the first network device. It can be seen that before the second A3 event is met, the terminal device obtains the first uplink authorization configured by the first network device for the terminal device and activated through the first A3 event, so that when the second A3 event is met, the terminal device can directly use the first uplink authorization to switch to the first network device, which can reduce the switching delay of the terminal device to access the first network device.

[0232] Correspondingly, the third network device receives the second information and sends the second information to the first network device; the first network device receives the second information from the third network device and sends the third information to the third network device; the third network device receives the third information from the first network device and sends the third information.

[0233] That is, when the first condition is met, the terminal device sends the second information to the second network device, the second network device sends the second information to the third network device, and the third network device sends the second information to the first network device, so that the first network device knows that the terminal device requests to activate the first uplink authorization. After the first network device activates the first uplink authorization, it sends the third information to the third network device, the third network device sends the third information to the second network device, and the second network device sends the third information to the terminal device, so that the terminal device knows that the first uplink authorization has been activated by the first network device.

[0234] In an optional implementation, the third network device sends the first threshold and the second threshold corresponding to the first network device. Correspondingly, the terminal device receives the first threshold and the second threshold corresponding to the first network device. Specifically, the third network device sends the first threshold and the second threshold corresponding to the first network device to the second network device, and the second network device then sends the first threshold and the second threshold corresponding to the first network device to the terminal device. Among them, the first threshold and the second threshold corresponding to the first network device can be understood as: the first threshold and the second threshold are the two thresholds required when the terminal device switches to the first network device, that is, the two thresholds used in the first condition and the second condition respectively when the terminal device switches to the first network device.

[0235] That is, the third network device configures the first threshold and the second threshold required for the terminal device to perform conditional switching to the first network device. Thus, the terminal device can determine how to perform conditional switching to the first network device based on the first threshold and the second threshold, as well as the first condition and the second condition.

[0236] Optionally, the event in the first condition and the second condition may also be an A4 event. Optionally, the event in the first condition and the second condition may also be an A5 event. Optionally, the two events in the first condition and the second condition may also be any two events among A3, A4 and A5 events. The embodiment of the present application does not limit the event type in the first condition and the second condition.

[0237] For example, the first condition is that the signal quality corresponding to the first network device is higher than threshold 1, the second condition is that the signal quality corresponding to the first network device is higher than threshold 2, and threshold 2 is greater than threshold 1, that is, the events in the first condition and the second condition are both A4 events. For another example, the first condition is that the signal quality corresponding to the second network device is lower than threshold 3, and the signal quality corresponding to the first network device is higher than threshold 4, the second condition is that the signal quality corresponding to the second network device is lower than threshold 5, and the signal quality corresponding to the first network device is higher than threshold 6, that is, the events in the first condition and the second condition are both A5 events. For another example, the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the serving cell by a first threshold, and the second condition is that the signal quality corresponding to the first network device is higher than threshold 1, that is, the event in the first condition is an A3 event, and the event in the second condition is an A4 event. For another example, the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the serving cell by a first threshold, and the second condition is that the signal quality corresponding to the second network device is lower than threshold 5, and the signal quality corresponding to the first network device is higher than threshold 6, that is, the event in the first condition is an A3 event, and the event in the second condition is an A5 event. For another example, the first condition is that the signal quality corresponding to the first network device is higher than threshold 1, the second condition is that the signal quality corresponding to the second network device is lower than threshold 5, and the signal quality corresponding to the first network device is higher than threshold 6, that is, the event in the first condition is event A4, and the event in the second condition is event A5.

[0238] Optionally, A1 and / or A2 events may also be added to the first condition and the second condition.

[0239] It can be understood that in the first condition and the second condition, the signal quality of the event can be an L1 measurement quantity or an L3 measurement quantity, that is, the signal quality corresponding to the first network device and the signal quality corresponding to the second network device can be obtained by the terminal device performing L1 measurement or L3 measurement.

[0240] Optionally, when the first condition is not met, the terminal device does not send the second information, that is, does not execute the above implementation mode b. Optionally, when the second condition is not met, the terminal device does not send uplink data to the first network device according to the first uplink authorization, that is, does not switch to the first network device.

[0241] Implementation method c: When a first condition is met, the terminal device sends second information, where the second information is used to request activation of a first uplink authorization configured by the first network device for the terminal device, and the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold; the terminal device receives third information, where the third information is used to indicate that the first network device has activated the first uplink authorization; when the terminal device receives a cell switching command from the second network device, the terminal device sends uplink data to the first network device according to the first uplink authorization to access the first network device.

[0242] Compared with the above-mentioned implementation mode b, the terminal device no longer determines whether to switch to the first network device according to the first uplink authorization based on whether the second condition is met, but determines whether to switch to the first network device according to the first uplink authorization based on whether a cell switching command is received from the second network device.

[0243] That is to say, when the first A3 event is satisfied, the terminal device determines that the terminal device may switch to the first network device, so it requests the first network device to activate the first uplink authorization through the second information to obtain the usable first uplink authorization. After receiving the second information, the first network device activates the first uplink authorization and notifies through the third information that the first uplink authorization has been activated. Therefore, when the terminal device receives the cell switching command from the second network device, it can directly send uplink data to the first network device according to the activated first uplink authorization to access the first network device.

[0244] It can be seen that in this implementation, before receiving the cell switching command from the second network device, the terminal device also obtains the first uplink authorization configured by the first network device for the terminal device and activated. Therefore, when the terminal device receives the cell switching command from the second network device, it can directly switch to the first network device according to the first uplink authorization, which can reduce the switching delay of the terminal device to access the first network device.

[0245] Optionally, other optional methods in this implementation c can refer to those described in the above implementation b, which will not be described in detail. For example, in implementation c, the event in the first condition can also be an A4 event or an A5 event.

[0246] Optionally, when the first condition is not met, the terminal device does not send the second information, that is, does not execute the above implementation mode c.

[0247] In an optional implementation, the terminal device executes implementation b or implementation c when the current time is later than or equal to the start time of the first time period. That is, the terminal device determines whether to start executing implementation b or implementation c based on the first time period. Optionally, the terminal device determines whether to start executing implementation b or implementation c based on the distance between the terminal device and the first network device and / or the first network device. For example, the terminal device determines to execute implementation b when the distance between the terminal device and the first network device is less than or equal to a first preset value, and / or the distance between the terminal device and the second network device is greater than a second preset value. It can be seen that the terminal device can perform both time-based conditional switching and geographic location-based conditional switching.

[0248] Optionally, when the elevation angle between the terminal device and the first network device is greater than the third preset value, and / or the elevation angle between the terminal device and the second network device is less than the fourth preset value, the above implementation mode b or implementation mode c is executed. Optionally, when the remaining service time of the terminal device from the second network device to the terminal device is less than the fifth preset value, and / or the remaining service time of the first network device to the terminal device is less than the seventh preset value, the above implementation mode b or implementation mode c is executed. Optionally, when the remaining coverage time of the satellite where the second network device is located to the terminal device is less than the sixth preset value, and / or the remaining coverage time of the satellite where the first network device is located to the terminal device is less than the eighth preset value, the above implementation mode b or implementation mode c is executed. Optionally, when the depression angle between the terminal device and the first network device is less than the ninth preset value, and / or the depression angle between the terminal device and the second network device is greater than the tenth preset value, the above implementation mode b or implementation mode c is executed.

[0249] The embodiments of the present application do not limit the specific forms of the second information and the third information exchanged between the above-mentioned devices, but the content requested by the second information exchanged between the devices is the same, and the content indicated by the third information exchanged between the devices is also the same.

[0250] It can be seen that in the embodiment of the present application, the third network device requests the first network device to configure an uplink authorization for the terminal device through the fifth information. The first network device indicates the confirmation information of the first network device configuring the uplink authorization for the terminal device through the first information. The terminal device determines the first uplink authorization configured by the first network device for the terminal device according to the first information, and sends uplink data to the first network device according to the first uplink authorization to access the first network device. Among them, the fifth information includes information for indicating the first time period, the first time period is the time period in which the terminal device performs switching to the first network device, and the time domain resources in the uplink authorization are located within the first time period. Thus, the first time domain resources in the first uplink authorization configured for the terminal device by the first network device according to the first time period are located within the first time period, so that the first time domain resources occupy less time, even if the first network device reserves less time domain resources in advance for the terminal device, it can reduce resource waste, that is, improve resource utilization.

[0251] In addition, before the terminal device switches to the first network device, it obtains the first uplink authorization configured by the first network device for the terminal device. Therefore, when the terminal device needs to switch to the first network device, it can directly use the obtained first uplink authorization to switch to the first network device, which can reduce the delay of the terminal device switching to the first network device.

[0252] The following takes the first network device as DU2, the second network device as DU1, the third network device as CU, DU1 as the DU deployed in the satellite currently providing services to the terminal device, DU2 as the DU deployed in the destination satellite to be accessed and switched by the terminal device, CU as the ground base station, and the first network device switches to the first network device according to the first uplink authorization configured by the first network device for the terminal device when receiving the cell switching command from the second network device as an example to explain the access switching method 100. Please refer to Figure 7 , Figure 7 This is the interaction process between the terminal device, DU1, DU2 and CU. Figure 7 As shown, the interaction process includes but is not limited to:

[0253] S701. The terminal device sends a first measurement report. Correspondingly, the CU receives the first measurement report.

[0254] It can be understood that the CU configures layer 3 measurements (L3 measurements) for the terminal device. The terminal device in the connected state performs measurements according to the layer 3 measurement configuration and obtains a first measurement report, that is, the first measurement report is an L3 measurement report. Optionally, the first measurement report includes user information of the terminal device, and the user information may include location information and motion state information of the terminal device.

[0255] The terminal device sending the first measurement report can be understood as: the terminal device sending the first measurement report to DU1, and DU1 then sends the first measurement report to CU. Thus, CU receives the first measurement report.

[0256] S7021. CU sends fifth information to DU2, the fifth information is used to request DU2 to configure uplink authorization for the terminal device, and the fifth information includes information used to indicate the first time period. Correspondingly, DU2 receives the fifth information from CU.

[0257] The first time period is the time period when the terminal device performs switching to DU2. For example, the first time period is the time period when the terminal device performs LTM to DU2, such as [ton, toff], ton is the time when the terminal device sends a layer 1 measurement report (L1 measurement report) to DU1, and toff is the time when the terminal device sends uplink data to DU2.

[0258] It is understandable that after receiving the first measurement report, the CU determines the DU sequence in which the terminal device subsequently performs multiple switchings, and infers the time period in which the terminal device switches to each DU, based on the movement trajectories of the multiple DUs (i.e., the multiple satellites deploying the multiple DUs) and the movement state information (position, movement speed, direction, etc.) of the terminal device. Thus, the CU sends the fifth information to the destination DU to which the terminal device is to access and switch in advance. For example, the CU sends the fifth information to the DU2 to which the terminal device is to access and switch, and the fifth information includes a first time period for indicating DU2, and the first time period corresponding to DU2 is the time period in which the terminal device performs switching to DU2.

[0259] Optionally, when the CU determines that the terminal device will switch to DU2 in the time period closest to the current time, the CU sends fifth information to DU2 for requesting DU2 to configure uplink authorization for the terminal device, and the fifth information includes a first time period corresponding to DU2 for indicating the first time period corresponding to DU2, and the first time period corresponding to DU2 is the time period in which the terminal device switches to DU2. The above-mentioned manner in which the CU sends the fifth information to DU2 enables DU2 to configure the time domain resources in the uplink authorization for the terminal device according to the first time period corresponding to DU2.

[0260] It can be seen that CU can request DU2 to configure an uplink authorization for the terminal device through the fifth information, which is conducive to the terminal device to subsequently switch to DU2 according to the uplink authorization configured by DU2 for the terminal device. In addition, the fifth information includes the first time period, and the first time period is the time period for the terminal device to perform the switch to DU2, which is conducive to DU2 determining the time domain resources in the uplink authorization configured for the terminal device according to the first time period, thereby reducing the time occupied by the time domain resources reserved by DU2 for the terminal device, and reducing resource waste.

[0261] S7022. DU2 sends first information, where the first information is used to instruct DU2 to configure confirmation information of uplink authorization for the terminal device. Correspondingly, the terminal device receives the first information.

[0262] After receiving the fifth information from CU, DU2 confirms whether uplink authorization can be configured for the terminal device. When DU2 confirms that uplink authorization can be configured for the terminal device, it sends the first information, which indicates confirmation information of DU2 configuring uplink authorization for the terminal device.

[0263] DU2 sends the first information, which can be understood as: DU2 sends the first information to CU, CU sends the first information to DU1, and DU1 sends the first information to the terminal device, so that the terminal device knows that DU2 has configured the confirmation information of the uplink authorization for the terminal device.

[0264] Optionally, the fifth information sent by CU to DU2 may be an uplink authorization reservation request, and the first information sent by DU2 to CU may be an uplink authorization reservation response. The uplink authorization reservation request is used to request DU2 to configure uplink authorization for the terminal device, and the uplink authorization reservation response is used to indicate confirmation information that DU2 has configured uplink authorization for the terminal device.

[0265] Optionally, the CU may also execute S7023, that is, the CU may send a user information establishment request to DU2. Correspondingly, DU2 may also execute S7024, that is, DU2 may send a user information modification response to the CU. Optionally, the fifth information is carried in the user information establishment request, and the first information may be carried in the user information modification response to reduce signaling overhead. For example, an uplink authorization reservation request is carried in a user information establishment request, and an uplink authorization reservation request response is carried in a user information modification response. Optionally, the user location information and motion status information of the terminal device are carried in the user information establishment request. Optionally, the user location information and motion status information of the terminal device are carried in the fifth information.

[0266] Optionally, the CU also sends an L1 / L2 handover configuration to the terminal device through an RRC reconfiguration message. The L1 / L2 handover configuration includes a target DU configuration list and a time period corresponding to each target DU in multiple target DUs. After receiving the RRC reconfiguration message carrying the L1 / L2 handover configuration, the terminal device stores the L1 / L2 handover configuration, applies other fields of RRCReconfiguration, and replies to the CU with an RRC reconfiguration completion message.

[0267] Optionally, the first information sent by the CU to the terminal device may be carried in an RRC reconfiguration message to reduce signaling overhead.

[0268] Optionally, the fifth information is also used to request to obtain the receiving beam of DU2, or is also used to request to obtain the transmitting beam of the terminal device. In this manner, the implementation of the fifth information and the first information can refer to the above S603, and will not be repeated here.

[0269] S7031. The terminal device determines, based on the first information, that DU2 is configured for the first uplink authorization of the terminal device, where the first uplink authorization includes a first time domain resource, and the first time domain resource is within a first time period.

[0270] It is understandable that, based on the first information, the terminal device learns that DU2 confirms that the uplink authorization is configured for the terminal device, thereby determining that DU2 is the first uplink authorization configured for the terminal device.

[0271] In an optional implementation manner, the first information is also used to indicate the first uplink authorization configured by DU2 for the terminal device. In this manner, the terminal device determines the first uplink authorization configured by DU2 for the terminal device according to the first information.

[0272] In another optional implementation, after DU2 enters the start time of the first time period, such as the time ton, the first uplink authorization is configured for the terminal device, and the fourth information is sent, and the fourth information is used to indicate the first uplink authorization. Correspondingly, the terminal device receives the fourth information and determines the first uplink authorization based on the fourth information. Optionally, the fourth information can be PDCCH.

[0273] It is understandable that the first uplink authorization configured by DU2 for the terminal device includes the first time domain resource, and the first time domain resource is located in the first time period. Therefore, the first time domain resource reserved by DU2 for the terminal device occupies less time, which can reduce resource waste.

[0274] S704. The terminal device sends a second measurement report to DU1. Correspondingly, DU1 receives the second measurement report from the terminal device.

[0275] The terminal device performs L1 measurement according to the L1 / L2 switching configuration sent by the CU, obtains the second measurement report of L1, and sends the second measurement report to DU1. The terminal device sends the second measurement report to DU1 so that DU1 determines whether the terminal device needs to switch to the target DU, for example, whether the terminal device needs to switch to DU2.

[0276] S705. DU1 sends a cell switching command to the terminal device. Correspondingly, the terminal device receives the cell switching command from DU1.

[0277] It is understandable that when DU1 determines that the terminal device needs to switch to DU2 according to the second measurement report, it sends a cell switching command to the terminal device. The cell switching command includes the identifier of DU2, and the cell switching command is used to instruct the terminal device to switch to DU2.

[0278] S706. The terminal device sends uplink data to DU2 according to the first uplink authorization. Correspondingly, DU2 receives uplink data from the terminal device according to the first uplink authorization.

[0279] When the terminal device receives the cell switching command from DU1, it learns that it needs to switch to DU2, and then sends uplink data to DU2 according to the first uplink authorization configured by DU2 for the terminal device. For example, when the terminal device receives the cell switching command from DU2, it sends uplink data to DU2 according to the first time domain resources and frequency domain resources in the first uplink authorization to access DU2.

[0280] Optionally, before DU2 receives uplink data from the terminal device according to the first uplink authorization, it may also execute S7032, that is, DU2 sends a first indication when the third condition is met, and the first indication is used to indicate that DU2 has activated the first uplink authorization. Thus, the terminal device receives the first indication and learns through the first indication that the first uplink authorization has been activated. Furthermore, when the terminal device receives a cell switching command from DU1, it may send uplink data to DU2 according to the activated first uplink authorization. Among them, the third condition can be referred to as described in the above-mentioned access switching method 100 and will not be repeated here. Optionally, DU2 does not send the first indication when the third condition is not met.

[0281] Optionally, when DU2 does not send the first indication for indicating that DU2 has activated the first uplink authorization, that is, when the terminal device does not receive the first indication, the terminal device can determine by itself whether the first uplink authorization has been activated. The terminal device can determine by itself whether the first uplink authorization has been activated based on whether the third condition is met. When the third condition is met, the terminal device determines that the first uplink authorization has been activated. Furthermore, when the terminal device receives the cell switching command from DU1, it can also send uplink data to DU2 according to the activated first uplink authorization.

[0282] Optionally, after the terminal device successfully accesses DU2, DU2 can inform CU through access success (ACCESS SUCCESS) signaling that the terminal device has successfully accessed DU2. Therefore, data transmission / reception between the terminal device and DU2 does not need to go through data forwarding between DU1 and CU, and the terminal device and DU2 can communicate directly.

[0283] Optionally, the CU sends fifth information to multiple candidate DUs of the terminal device, and the fifth information sent to each of the multiple candidate DUs is used to request the candidate DU to configure uplink authorization for the terminal device, and the multiple DUs include DU2. The terminal device learns through the first information fed back by each candidate DU that each of the multiple candidate DUs confirms that uplink authorization is configured for the terminal device. Thus, after the terminal device performs switching to DU2, it can also perform continuous LTM to access other candidate DUs in the multiple candidate DUs except DU2. In addition, the terminal device can delete the relevant configuration about the source cell / DU after each switching is completed.

[0284] It can be seen that CU requests DU2 to configure uplink authorization for the terminal device through the fifth information. DU2 indicates confirmation information that DU2 configures uplink authorization for the terminal device through the first information. The terminal device determines that DU2 is the first uplink authorization configured for the terminal device, and when receiving the cell switching command from DU1, it sends uplink data to DU2 according to the first uplink authorization to access DU2. The first time domain resource in the first uplink authorization used when the terminal device switches to DU2 is located in the first time period, and the first time period is the time period when the terminal device performs switching to DU2, which can reduce the waste of resources when the terminal device switches to DU2. In addition, before receiving the cell switching command, the terminal device obtains the first uplink authorization used for switching to DU2, which can reduce the delay of the terminal device switching to DU2.

[0285] The following takes the first network device as DU2, the second network device as DU1, the third network device as CU, DU1 as the DU deployed in the satellite currently providing services to the terminal device, DU2 as the DU deployed in the destination satellite to be accessed and switched by the terminal device, CU as the ground base station, and the first network device switches to the first network device according to the first uplink authorization configured by the first network device for the terminal device when the first condition is met and the second condition is met, as an example to illustrate the access switching method 100. Please refer to Figure 8 , Figure 8 This is the interaction process between the terminal device, DU1, DU2 and CU. Figure 8 As shown, the interaction process includes but is not limited to:

[0286] S801. The terminal device sends a first measurement report. Correspondingly, the CU receives the first measurement report.

[0287] S8021. CU sends fifth information to DU2, the fifth information is used to request DU2 to configure uplink authorization for the terminal device, and the fifth information includes information used to indicate the first time period. Correspondingly, DU2 receives the fifth information from CU.

[0288] S8022. DU2 sends the first information, where the first information is used to indicate confirmation information that DU2 configures uplink authorization for the terminal device.

[0289] Optionally, CU may also execute S8023, and DU2 may also execute S8024. The implementation methods thereof may be referred to above and will not be described in detail.

[0290] Optionally, the fifth information is also used to request to obtain the receiving beam of DU2, or is also used to request to obtain the transmitting beam of the terminal device. In this manner, the implementation of the fifth information and the first information can refer to the above S603, and will not be repeated here.

[0291] S803. The terminal device determines, based on the first information, a first uplink authorization configured by DU2 for the terminal device, where the first uplink authorization includes a first time domain resource, and the first time domain resource is within a first time period.

[0292] In the embodiments of the present application, the implementation of S801 to S803 can refer to the implementation of S701 to S703 described above, and will not be described in detail.

[0293] S804. When the first condition is met, the terminal device sends a second message, the second message is used to request activation of the first uplink authorization configured by DU2 for the terminal device, the first condition being that the signal quality corresponding to DU2 is higher than the signal quality corresponding to DU1 by a first threshold. Accordingly, DU2 receives the second message.

[0294] When the signal quality corresponding to DU2 is higher than the signal quality corresponding to DU1 by a first threshold, it indicates that DU2 may enter the service area of ​​the terminal device, that is, the terminal device may switch from DU1 to DU2. Therefore, when the first condition is met, the terminal device sends the second information to request DU2 to activate the first uplink authorization configured for the terminal device, which is conducive to the subsequent terminal device switching to DU2 according to the activated first uplink authorization.

[0295] When the first condition is met, the terminal device sends the second information, which can be understood as: when the first condition is met, the terminal device sends the second information to DU1, DU1 sends the second information to CU, and CU sends the second information to DU2, so that DU2 obtains the second information sent by the terminal device.

[0296] Optionally, when the first condition is not met, the terminal device does not send the second information, and thus does not execute the steps after S804.

[0297] S805. DU2 sends third information, where the third information is used to indicate that DU2 has activated the first uplink authorization. Correspondingly, the terminal device receives the third information.

[0298] It is understandable that after receiving the second information, DU2 activates the first uplink authorization configured for the terminal device and sends the third information, indicating that DU2 has activated the first uplink authorization through the third information.

[0299] DU2 sends the third information, which can be understood as: DU2 sends the third information to CU, CU sends the third information to DU1, and DU1 sends the third information to the terminal device, so that the terminal device knows that the first uplink authorization has been activated by DU2.

[0300] S806a. The terminal device sends uplink data to DU2 according to the first uplink authorization when the second condition is met, and the second condition is that the signal quality corresponding to DU2 is higher than the signal quality corresponding to DU1 by a second threshold.

[0301] The second threshold is greater than the first threshold, and the first threshold and the second threshold are configured by the CU for the terminal device.

[0302] When the signal quality corresponding to DU2 is higher than the signal quality corresponding to DU1 by a second threshold, the terminal device switches from DU1 to DU2. Therefore, when the second condition is satisfied, the terminal device sends uplink data to DU2 according to the activated first uplink grant to access DU2.

[0303] Optionally, the events in the above-mentioned first condition and the second condition may also be A4 events, or A5 events, or any two of A3 events, A4 events and A5 events. The specific implementation methods thereof may be referred to in the above-mentioned access switching method 100 and will not be repeated here.

[0304] Optionally, when the second condition is not met, the terminal device does not execute the step of sending uplink data to DU2 according to the first uplink authorization, that is, does not perform switching to DU2.

[0305] S806b. When the terminal device receives the cell switching command from DU1, it sends uplink data to DU2 according to the first uplink authorization.

[0306] That is, the terminal device may determine whether to send uplink data to DU2 regardless of whether the second condition is satisfied. When receiving the cell switching command from DU1, the terminal device sends uplink data to DU2 according to the activated first uplink grant.

[0307] In this method, the terminal device also sends a layer 1 measurement report to DU1; DU1 determines whether the terminal device needs to switch to DU2 based on the layer 1 measurement report from the terminal device; when DU1 determines that the terminal device needs to switch to DU2, it sends a cell switching command to the terminal device to instruct the terminal device to switch to DU2.

[0308] It is understandable that the terminal device executes S806a or executes S806b to switch to the first network device.

[0309] Optionally, after the terminal device successfully accesses DU2, DU2 may inform CU through ACCESS SUCCESS signaling that the terminal device has successfully accessed DU2. The implementation method thereof may refer to the above Figure 7 The access switching method is described in the figure and will not be repeated here.

[0310] Optionally, after the terminal device completes the switch to DU2, it can also perform continuous LTM switching. The implementation method can be found in the above Figure 7 The access switching method is described in the figure and will not be repeated here.

[0311] It can be seen that CU requests DU2 to configure an uplink authorization for the terminal device through the fifth information. DU2 indicates confirmation information that DU2 configures the uplink authorization for the terminal device through the first information. The terminal device determines that DU2 is the first uplink authorization configured for the terminal device based on the first information, and when the first condition is met, requests DU2 to activate the first uplink authorization through the second information, and when the second condition is met, sends uplink data to DU2 based on the activated first uplink authorization to access DU2. Among them, the first time domain resources included in the first uplink authorization are located in the first time period, which can reduce the time domain resources reserved by DU2 for the terminal device and reduce resource waste. In addition, before the second condition is met, the terminal device has determined that DU2 is the first uplink authorization configured for the terminal device and has been activated. Therefore, when the second condition is met, the terminal device can directly send uplink data to DU2 based on the activated first uplink authorization, which can reduce the switching delay of the terminal device to DU2.

[0312] Alternatively, CU requests DU2 to configure an uplink authorization for the terminal device through the fifth information. DU2 indicates confirmation information that DU2 configures the uplink authorization for the terminal device through the first information. The terminal device determines the first uplink authorization configured by DU2 for the terminal device based on the first information, and requests DU2 to activate the first uplink authorization through the second information when the first condition is met. Thus, when the terminal device receives the cell switching command from DU1, it sends uplink data to DU2 according to the activated first uplink authorization to access DU2. Among them, the first time domain resources included in the first uplink authorization are still within the first time period, which can reduce resource waste. In addition, before receiving the cell switching command from DU1, the terminal device has determined that DU2 is the first uplink authorization configured for the terminal device and has been activated. Thus, when the terminal device receives the cell switching command from DU1, it can also directly send uplink data to DU2 according to the activated first uplink authorization, which can reduce the switching delay of the terminal device to DU2.

[0313] The present application embodiment also provides an access switching method 200. Fig. 9 2 is an interactive schematic diagram of the access switching method 200. The access switching method 200 is described from the perspective of the interaction between the terminal device, the first network device, the second network device and the third network device. The access switching method 200 includes but is not limited to the following steps:

[0314] S901. When the first condition is met, the terminal device sends sixth information for requesting uplink authorization of the terminal device, and the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold. Accordingly, the first network device receives the sixth information.

[0315] In the embodiment of the present application, the signal quality corresponding to the first network device and the signal quality corresponding to the second network device can be referred to in the above-mentioned access switching method 100, which will not be repeated here.

[0316] It is understandable that when the first condition is met, the terminal device sends the sixth information to the second network device. The second network device sends the sixth information to the third network device. After the third network device receives the sixth information from the second network device, it determines that the terminal device will switch to the first network device based on the ephemeris conditions of each network device. Thus, the third network device sends the sixth information to the first network device so that the first network device configures uplink authorization for the terminal device. Optionally, when sending an RRC reconfiguration message, the third network device determines the order in which the terminal device switches to multiple network devices, such as determining the order in which the terminal device switches to multiple DUs, that is, the third network device can determine the order in which the terminal device switches to multiple network devices in advance. Thus, when the third network device receives the sixth information, it sends the sixth information to the first network device to which the terminal device will switch, so that the first network device configures uplink authorization for the terminal device.

[0317] The first condition is that when the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, the terminal device may switch to the first network device. Therefore, the terminal device sends the sixth information to request the uplink authorization of the terminal device through the sixth information, so that it can subsequently switch to the first network device according to the obtained uplink authorization.

[0318] Optionally, when the first condition is not met, the terminal device does not send the sixth information, and thus does not execute the steps after S901.

[0319] S902. The first network device sends seventh information to the third network device, where the seventh information is used to indicate the first uplink authorization configured by the first network device for the terminal device. Correspondingly, the third network device receives the seventh information from the first network device.

[0320] In an optional implementation, after the first network device obtains the sixth information, it configures the first uplink authorization for the terminal device, and indicates the first uplink authorization configured by the first network device for the terminal device through the seventh information. That is, after the first network device obtains the sixth information, it configures the first uplink authorization to the terminal device by means of a configured grant.

[0321] In another optional implementation, the seventh information is PDCCH, that is, the first uplink grant is carried in PDCCH. In this method, the first network device configures the first uplink grant to the terminal device by means of dynamic grant.

[0322] Optionally, the sixth information is also used to request the acquisition of the receiving beam of the first network device. Optionally, the sixth information is also used to request the acquisition of the transmitting beam of the terminal device. When the sixth information is also used to request the acquisition of the receiving beam of the first network device or the transmitting beam of the terminal device, the implementation of the sixth information and the seventh information can refer to the implementation of the fifth information and the first information in S603 above, and will not be repeated here.

[0323] S903. The third network device sends the seventh information. Correspondingly, the terminal device receives the seventh information.

[0324] It can be understood that the third network device sends the seventh information to the second network device, and the second network device then sends the seventh information to the terminal device. Thus, the terminal device obtains the first uplink authorization configured by the first network device for the terminal device.

[0325] S904a. The terminal device sends uplink data to the first network device according to the first uplink authorization to access the first network device when the second condition is met, and the second condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold.

[0326] The second threshold is greater than the first threshold. Optionally, other implementations of the first condition and the second condition can refer to the above S605, which will not be described in detail.

[0327] When the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, it indicates that the terminal device needs to switch to the first network device. The terminal device then sends uplink data to the first network device according to the first uplink authorization configured for the terminal device by the first network device to access the first network device.

[0328] Optionally, when the second condition is not met, the terminal device does not execute the step of sending uplink data to the first network device according to the first uplink authorization.

[0329] S904b. When the terminal device receives the cell switching command from the second network device, it sends uplink data to the first network device according to the first uplink authorization to access the first network device.

[0330] It is understandable that the terminal device does not determine whether to switch to the first network device based on the second condition, but the terminal device determines whether to switch to the first network device based on whether a cell switching command is received from the second network device.

[0331] The second network device determines whether the terminal device needs to switch to the first network device based on the L1 measurement report reported by the terminal device. When the second network device determines that the terminal device needs to switch to the first network device, it sends a cell switching command to the terminal device so that the terminal device switches to the first network device. Thus, when the terminal device receives the cell switching command from the second network device, it sends uplink data to the first network device according to the first uplink authorization configured by the first network device for the terminal device to access the first network device.

[0332] It is understandable that the terminal device executes S904a or executes S904b to switch to the first network device.

[0333] Optionally, the third network device also sends the first threshold and the second threshold corresponding to the first network device, or sends the first threshold corresponding to the first network device. Correspondingly, the terminal device receives the first threshold and the second threshold corresponding to the first network device, or receives the first threshold corresponding to the first network device. Optionally, the first threshold and the second threshold corresponding to the first network device, or the first threshold corresponding to the first network device, are carried in the RRC reconfiguration information to reduce signaling overhead.

[0334] In the embodiment of the present application, when the first condition is met, the terminal device obtains the uplink authorization of the terminal device through the sixth information request, and obtains the first uplink authorization configured by the first network device for the terminal device through the seventh information. Furthermore, when the second condition is met, or when the cell switching command is received from the second network device, the terminal device sends uplink data to the first network device according to the first uplink authorization to access the first network device.

[0335] It can be seen that the terminal device obtains the first uplink authorization configured for the terminal device by the first network device before the second condition is met or before receiving the cell switching command from the second network device. Then, when the second condition is met or the cell switching command is received from the second network device, the terminal device can directly send uplink data to the first network device according to the first uplink authorization, thereby reducing the switching delay of the terminal device to the first network device.

[0336] The following takes the first network device as DU2, the second network device as DU1, the third network device as CU, DU1 as the DU deployed in the satellite currently providing services to the terminal device, DU2 as the DU deployed in the destination satellite to be accessed and switched by the terminal device, and CU as the ground base station as an example to explain the access switching method 200. Fig.10 , Fig.10 This is the interaction process between the terminal device, DU1, DU2 and CU.

[0337] like Fig.10 As shown, the interaction process includes but is not limited to:

[0338] S1001. The terminal device sends a first measurement report. Correspondingly, the CU receives the first measurement report.

[0339] S10021. CU sends a user information establishment request to DU2. Correspondingly, DU2 receives the user information establishment request from CU.

[0340] S10022. DU2 sends a user information modification response to CU. Correspondingly, CU receives the user information modification response from DU2.

[0341] S1003. CU sends an RRC reconfiguration message. Correspondingly, the terminal device receives the RRC reconfiguration message.

[0342] S1004. The terminal device sends an RRC reconfiguration completion message. Correspondingly, the CU receives the RRC reconfiguration completion message.

[0343] It is understandable that S1001 to S1004 can refer to the above Figure 8 The description of the relevant steps in will not be repeated here.

[0344] S1005. When the first condition is met, the terminal device sends sixth information for requesting uplink authorization of the terminal device, and the first condition is that the signal quality corresponding to DU2 is higher than the signal quality corresponding to DU1 by a first threshold. Accordingly, DU2 receives the sixth information.

[0345] When the signal quality corresponding to DU2 of the terminal device is higher than the signal quality corresponding to DU1 by a first threshold, it indicates that the terminal device may switch to DU2. Then, when the first condition is met, the terminal device sends the sixth information to request the uplink authorization configured by DU2 for the terminal device.

[0346] It is understandable that when the first condition is met, the terminal device sends the sixth information to DU1, DU1 sends the sixth information to CU, and CU sends the sixth information to DU2. Thus, DU2 receives the sixth information.

[0347] Optionally, when the first condition is not met, the terminal device does not send the sixth information, and thus does not execute the steps after S1005.

[0348] S1006. DU2 sends seventh information to CU, where the seventh information is used to indicate the first uplink authorization configured by DU2 for the terminal device. Correspondingly, CU receives the seventh information from DU2.

[0349] It is understandable that after receiving the sixth information, DU2 configures the first uplink authorization for the terminal device, and indicates to CU through the seventh information the first uplink authorization configured by DU2 for the terminal device.

[0350] Optionally, the sixth information is also used to request the acquisition of the receiving beam of DU2. Optionally, the sixth information is also used to request the acquisition of the transmitting beam of the terminal device. When the sixth information is also used to request the acquisition of the receiving beam of DU2 or the transmitting beam of the terminal device, the implementation of the sixth information and the seventh information can refer to the implementation of the fifth information and the first information in S603 above, and will not be repeated here.

[0351] S1007. CU sends the seventh information. Correspondingly, the terminal device receives the seventh information.

[0352] It is understandable that the CU sends the seventh information to DU1, and DU1 then sends the seventh information to the terminal device. Thus, the terminal device obtains the first uplink authorization configured by DU2 for the terminal device through the seventh information.

[0353] S1008a. When the second condition is met, the terminal device sends uplink data to DU2 according to the first uplink authorization to access DU2, and the second condition is that the signal quality corresponding to DU2 is higher than the signal quality corresponding to DU1 by a second threshold.

[0354] S1008b. When receiving the cell switching command from DU1, the terminal device sends uplink data to DU2 according to the first uplink grant to access DU2.

[0355] It is understandable that the terminal device executes S1008a or S1008b and switches to DU2.

[0356] Optionally, when the second condition is not met, the terminal device does not execute the step of sending uplink data to DU2 according to the first uplink authorization.

[0357] Optionally, when the terminal device does not receive a cell switching command from DU1, the step of sending uplink data to DU2 according to the first uplink authorization is not performed.

[0358] Optionally, after the terminal device successfully accesses DU2, DU2 may inform CU through ACCESS SUCCESS signaling that the terminal device has successfully accessed DU2. The implementation method thereof may refer to the above Figure 7 The access switching method is described in the figure and will not be repeated here.

[0359] Optionally, after the terminal device completes the switch to DU2, it can also perform continuous LTM switching. The implementation method can be found in the above Figure 7 The access switching method is described in the figure and will not be repeated here.

[0360] When the second condition is met, the terminal device sends uplink data to DU2 according to the first uplink authorization configured for the terminal device by DU2 to access DU2; or, when the terminal device receives a cell switching command from DU1, it sends uplink data to DU according to the first uplink authorization configured for the terminal device by DU2 to access DU2. In both methods, the terminal device obtains the first uplink authorization configured for the terminal device by DU2 before switching to DU2, so that when the terminal device switches to DU2, it can directly send uplink data to DU2 according to the obtained first uplink authorization, which can reduce the delay when the terminal device switches to DU2.

[0361] The embodiment of the present application also provides an access switching method 300. Fig.11 3 is a flow chart of the access switching method 300. The access switching method 300 is described from the perspectives of the terminal device, the first network device and the third network device. The access switching method 200 includes but is not limited to the following steps:

[0362] S1101. The third network device sends eighth information to the first network device, where the eighth information is used to request to obtain a random access resource of the terminal device.

[0363] It is understandable that when the third network device determines that the terminal device will switch to the first network device based on the ephemeris conditions of multiple network devices and the location information of the terminal device, it sends the eighth information to the first network device to request the first network device to configure random access resources for the terminal device.

[0364] S1102. The first network device sends ninth information to the third network device, where the ninth information is used to indicate a first random access resource configured by the first network device for the terminal device.

[0365] After receiving the eighth information from the third network device, the first network device configures a first random access resource for the terminal device, and indicates the first random access resource to the third network device through the ninth information.

[0366] S1103. The third network device sends the ninth information. Correspondingly, the terminal device receives the ninth information.

[0367] Understandably, the third network device sends the ninth information to the second network device, and the second network device then sends the ninth information to the terminal device. Thus, the terminal device obtains the first random access resource configured by the first network device for the terminal device through the ninth information.

[0368] S1104. When receiving the cell switching command from the second network device, the terminal device initiates random access to the first network device according to the first random access resource to access the first network device.

[0369] It is understandable that the terminal device reports the L1 measurement report to the second network device, and the second network device determines whether the terminal device needs to switch to the first network device based on the L1 measurement report reported by the terminal device. When the second network device determines that the terminal device needs to switch to the first network device based on the L1 measurement report reported by the terminal device, it sends a cell switching command to the terminal device to instruct the terminal device to switch to the first network device. Thus, when the terminal device receives the cell switching command from the second network device, it initiates random access to the first network device based on the obtained first random access resource to access the first network device.

[0370] In the embodiment of the present application, the third network device requests the first network device to configure a random access resource for the terminal device through the eighth information. Thus, before the terminal device receives the cell switching command from the second network device, it obtains the first random access resource configured for the terminal device by the first network device. Furthermore, when the terminal device receives the cell switching command from the second network device, it can directly initiate random access to the first network device based on the obtained first random access resource, which can reduce the switching delay of the terminal device to the first network device.

[0371] The following takes the first network device as DU2, the second network device as DU1, the third network device as CU, DU1 as the DU deployed in the satellite currently providing services to the terminal device, DU2 as the DU deployed in the destination satellite to be accessed and switched by the terminal device, and CU as the ground base station as an example to illustrate the access switching method 300. Fig.12 , Fig.12 This is the interaction process between the terminal device, DU1, DU2 and CU.

[0372] like Fig.12 As shown, the interaction process includes but is not limited to:

[0373] S1201. The terminal device sends a first measurement report. Correspondingly, the CU receives the first measurement report.

[0374] It is understandable that the terminal device performs measurement according to the L3 measurement configuration of the CU to obtain the first measurement report. The terminal device sends the first measurement report to DU1, and DU1 sends the first measurement report to the CU. Thus, the CU receives the first measurement report.

[0375] S12021.CU sends the eighth information to DU2, where the eighth information is used to request random access resources of the terminal device.

[0376] When the CU determines that the terminal device will switch to DU2, it sends the eighth information to DU2 to request DU2 to configure random access resources for the terminal device, so as to facilitate the terminal device to perform random access to DU2 subsequently.

[0377] S12022. DU2 sends ninth information, where the ninth information is used to indicate the first random access resource configured by DU2 for the terminal device. Correspondingly, the terminal device receives the ninth information.

[0378] After receiving the eighth information, DU2 configures the first random access resource for the terminal device, and sends the first random access resource configured for the terminal device through the ninth information.

[0379] It is understandable that DU2 sends the ninth information to CU, CU sends the ninth information to DU1, and DU1 sends the ninth information to the terminal device. Thus, the terminal device obtains the first random access resource configured by DU2 for the terminal device through the ninth information.

[0380] Optionally, the CU may further execute S12023, that is, the CU sends a user information establishment request to DU2. Accordingly, DU2 receives the user information establishment request from the CU. Optionally, the DU2 may further execute S12024, that is, the DU2 sends a user information modification response to the CU. Accordingly, the CU receives the user information modification response from DU2.

[0381] Optionally, the eighth information is carried in the user information establishment request, and the ninth information sent by DU2 to CU is carried in the user information modification response. Optionally, the ninth information sent by CU can be carried in the RRC reconfiguration message. This method can reduce signaling overhead.

[0382] S1203. CU sends an RRC reconfiguration message. Correspondingly, the terminal device receives the RRC reconfiguration message.

[0383] S1204. The terminal device sends an RRC reconfiguration completion message. Correspondingly, the CU receives the RRC reconfiguration completion message.

[0384] S1205. The terminal device sends a second measurement report to DU1. Correspondingly, DU1 receives the second measurement report from the terminal device.

[0385] S1206. DU1 sends a cell switching command to the terminal device. Correspondingly, the terminal device receives the cell switching command from DU1.

[0386] S1207. The terminal device initiates random access to DU2 according to the first random access resource.

[0387] The second measurement report is an L1 measurement report.

[0388] When DU1 determines that the terminal device needs to switch to DU2 based on the second measurement report reported by the terminal device, it sends a cell switching command to the terminal device to instruct the terminal device to switch to DU2. Therefore, when the terminal device receives the cell switching command from DU1, it initiates random access to DU2 based on the obtained first random access resource, that is, performs random access to DU2.

[0389] In the embodiment of the present application, the method by which the first network device activates the first random access resource, and the method by which the terminal device determines whether the first random access resource has been activated, can respectively refer to the method by which the first network device determines the activation of the first uplink authorization, and the method by which the terminal device determines whether the first uplink authorization has been activated in the above-mentioned access switching method 100, and will not be repeated here.

[0390] It can be seen that before receiving the cell switching command from DU1, the terminal device obtains the first random access resource configured by DU2 for the terminal device. Therefore, when the terminal device receives the cell switching command from DU1, it can directly use the obtained first random access resource to initiate random access to DU2, which can reduce the switching delay of the terminal device to switch to DU2.

[0391] With respect to the technical solutions described above, the corresponding device implementation solutions are further described below.

[0392] In order to implement the functions of the method provided in the above embodiment of the present application, the terminal device and the network device (the first network device or the third network device) may include a hardware structure and / or a software module, and implement the above functions in the form of a hardware structure, a software module, or a hardware structure plus a software module. Whether a function of the above functions is executed in the form of a hardware structure, a software module, or a hardware structure plus a software module depends on the specific application and design constraints of the technical solution.

[0393] like Fig.13As shown, an embodiment of the present application provides a communication device 1300. The communication device 1300 may be a component of a terminal device (e.g., an integrated circuit, a chip, etc.), or a component of a network device (a first network device or a third network device) (e.g., an integrated circuit, a chip, etc.). The communication device 1300 may also be other communication units for implementing the method in the method embodiment of the present application. The communication device 1300 may include: a communication unit 1301 and a processing unit 1302. Optionally, a storage unit 1303 may also be included.

[0394] In one possible design, Fig.13 One or more units may be implemented by one or more processors, or by one or more processors and memories; or by one or more processors and transceivers; or by one or more processors, memories, and transceivers, which are not limited in the embodiments of the present application. The processor, memory, and transceiver may be provided separately or integrated.

[0395] The communication device 1300 has the functions of the terminal device described in the embodiment of the present application, or the functions of the network device (the first network device or the third network device). For example, the communication device 1300 includes a module or unit or means corresponding to the steps involved in the terminal device described in the embodiment of the present application, and the functions or units or means can be implemented by software, or by hardware, or by hardware executing the corresponding software implementation, or by a combination of software and hardware. For details, please refer to the corresponding description in the aforementioned corresponding method embodiment.

[0396] In one possible design, a communication device 1300 may include: a processing unit 1302 and a communication unit 1301;

[0397] The communication unit 1301 is used to receive first information, where the first information is used to indicate confirmation information that a first network device configures uplink authorization for the terminal device, and the first network device is a destination network device to be switched to by the terminal device;

[0398] The processing unit 1302 is configured to determine, according to the first information, a first uplink authorization configured by the first network device for the terminal device, where the first uplink authorization includes a first time domain resource, the first time domain resource is within a first time period, and the first time period is a time period in which the terminal device performs a handover to the first network device;

[0399] The processing unit 1302 is further configured to switch to the first network device according to the first uplink authorization.

[0400] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the above-mentioned method embodiment and will not be described in detail here.

[0401] The embodiments of the present application and the method embodiments shown above are based on the same concept, and the technical effects they bring are also the same. For the specific principles, please refer to the description of the embodiments shown above, and no further details will be given.

[0402] In another possible design, a communication device 1300 may include: a processing unit 1302 and a communication unit 1301, wherein the processing unit 1302 is configured to process a signal / signaling;

[0403] The communication unit 1301 is configured to send fifth information to the first network device, where the fifth information is used to request the first network device to configure an uplink authorization for the terminal device, where the fifth information includes information indicating a first time period, where the time domain resources in the uplink authorization are within the first time period, where the first time period is a time period in which the terminal device performs a handover to the first network device, and where the first network device is a destination network device to be accessed and switched by the terminal device;

[0404] The communication unit 1301 is further used to receive first information from the first network device and send the first information, where the first information is used to indicate confirmation information that the first network device configures uplink authorization for the terminal device.

[0405] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the method embodiment and will not be described in detail here.

[0406] The embodiments of the present application and the method embodiments shown above are based on the same concept, and the technical effects they bring are also the same. For the specific principles, please refer to the description of the embodiments shown above, and no further details will be given.

[0407] In yet another possible design, a communication device 1300 may include: a processing unit 1302 and a communication unit 1301;

[0408] The communication unit 1301 is configured to receive fifth information from a third network device, the fifth information being used to request the first network device to configure an uplink authorization for the terminal device, the fifth information including information indicating a first time period, the time domain resources in the uplink authorization being within the first time period, the first time period being a time period in which the terminal device performs a handover to the first network device, and the first network device being a destination network device to be accessed and switched by the terminal device;

[0409] The communication unit 1301 is further configured to send first information to the third network device, where the first information is used to indicate confirmation information that the first network device configures uplink authorization for the terminal device;

[0410] The processing unit 1302 is used to receive uplink data from the terminal device according to a first uplink authorization configured for the terminal device, where the first uplink authorization includes a first time domain resource, and the first time domain resource is located in the first time period.

[0411] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the above-mentioned method embodiment and will not be described in detail here.

[0412] The embodiments of the present application and the method embodiments shown above are based on the same concept, and the technical effects they bring are also the same. For the specific principles, please refer to the description of the embodiments shown above, and no further details will be given.

[0413] In yet another possible design, a communication device 1300 may include: a processing unit 1302 and a communication unit 1301, wherein the processing unit 1302 is configured to process a signal / signaling;

[0414] The communication unit 1301 is configured to send sixth information when a first condition is met, where the sixth information is used to request an uplink authorization for the terminal device, the first condition being that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a first threshold, the first network device is a target network device to be accessed and switched by the terminal device, and the second network device is a network device currently providing services for the terminal device;

[0415] The communication unit 1301 is further used to receive seventh information, where the seventh information is used to indicate a first uplink authorization configured by the first network device for the terminal device;

[0416] The communication unit 1301 is also used to send uplink data to the first network device according to the first uplink authorization to access the first network device when a second condition is met, and the second condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, and the second threshold is greater than the first threshold; or, when a cell switching command is received from the second network device, send uplink data to the first network device according to the first uplink authorization to access the first network device.

[0417] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the above-mentioned method embodiment and will not be described in detail here.

[0418] In yet another possible design, a communication device 1300 may include: a processing unit 1302 and a communication unit 1301, wherein the processing unit 1302 is configured to process a signal / signaling;

[0419] The communication unit 1301 is configured to receive sixth information and send the sixth information to the first network device, where the sixth information is used to request an uplink authorization of the terminal device, and the sixth information is sent by the terminal device when a first condition is met, where the first condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a first threshold, the first network device is the destination network device to be accessed and switched by the terminal device, and the second network device is the network device currently providing services for the terminal device;

[0420] The communication unit 1301 is further used to receive seventh information from the first network device and send the seventh information, where the seventh information is used to indicate a first uplink authorization configured by the first network device for the terminal device.

[0421] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the above-mentioned method embodiment and will not be described in detail here.

[0422] In yet another possible design, a communication device 1300 may include: a processing unit 1302 and a communication unit 1301;

[0423] The communication unit 1301 is configured to receive sixth information from a third network device, where the sixth information is used to request an uplink authorization of a terminal device, and the sixth information is sent by the terminal device to the third network device when a first condition is met, where the first condition is that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a first threshold, the first network device is a target network device to be accessed and switched by the terminal device, and the second network device is a network device currently providing services for the terminal device;

[0424] The communication unit 1301 is further configured to send seventh information to the third network device, where the seventh information is used to indicate a first uplink authorization configured by the first network device for the terminal device;

[0425] The processing unit 1302 is used to receive uplink data from the terminal device according to the first uplink authorization.

[0426] In addition, in this aspect, other optional implementations of the communication device can refer to the relevant content of the above-mentioned method embodiment and will not be described in detail here.

[0427] The embodiments of the present application and the method embodiments shown above are based on the same concept, and the technical effects they bring are also the same. For the specific principles, please refer to the description of the embodiments shown above, and no further details will be given.

[0428] The present application embodiment further provides a communication device 1400, Fig.14 1 is a schematic diagram of the structure of the communication device 1400. The communication device 1400 may be a terminal device, or a chip, a chip system, or a processor that supports the terminal device to implement the above method; or, it may be a network device (a first network device or a third network device), or a chip, a chip system, or a processor that supports the network device (a first network device or a third network device) to implement the above method. The device may be used to implement the method described in the above method embodiment, and the details may refer to the description in the above method embodiment.

[0429] The communication device 1400 may include one or more processors 1401. The processor 1401 may be a general-purpose processor or a dedicated processor, etc. For example, it may be a baseband processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component or a central processing unit (CPU). The baseband processor may be used to process the communication protocol and communication data, and the central processing unit may be used to control the communication device (such as a base station, a baseband chip, a terminal, a terminal chip, a distributed unit DU or a centralized unit CU, etc.), execute a software program, and process the data of the software program.

[0430] Optionally, the communication device 1400 may include one or more memories 1402, on which instructions 1404 may be stored, and the instructions may be executed on the processor 1401, so that the communication device 1400 performs the method described in the above method embodiment. Optionally, data may also be stored in the memory 1402. The processor 1401 and the memory 1402 may be provided separately or integrated together.

[0431] Optionally, the communication device 1400 may further include a transceiver 1405 and an antenna 1406. The transceiver 1405 may be referred to as a transceiver unit, a transceiver, or a transceiver circuit, etc., for implementing a transceiver function. The transceiver 1405 may include a receiver and a transmitter, the receiver may be referred to as a receiver or a receiving circuit, etc., for implementing a receiving function; the transmitter may be referred to as a transmitter or a transmitting circuit, etc., for implementing a transmitting function.

[0432] The communication device 1400 is a terminal device: the processor 1401 is used to execute S604 and S605 in the above-mentioned access switching method 100, and is used to execute S1104 in the above-mentioned access switching method 300; the transceiver 1405 is used to execute S603 in the above-mentioned access switching method 100, and is used to execute S901, S903, and S904a or S904b in the above-mentioned access switching method 200, and is used to execute S1103 in the above-mentioned access switching method 300.

[0433] The communication device 1400 is a first network device: the transceiver 1405 is used to execute S601 and S602 in the access switching method 100, to execute S901 and S902 in the access switching method 100, and to execute S1101 and S1102 in the access switching method 300.

[0434] The communication device 1400 is a third network device: the transceiver 1405 is used to execute S601 and S602 in the access switching method 100, to execute S901 and S903 in the access switching method 200, and to execute S1101 and S1102 in the access switching method 300.

[0435] Optionally, the processor 1401 may store an instruction 1403, and the instruction 1403 runs on the processor 1401, so that the communication device 1400 can execute the method described in the above method embodiment. The instruction 1403 may be fixed in the processor 1401, in which case the processor 1401 may be implemented by hardware.

[0436] The embodiments of the present application and the method embodiments shown in the above-mentioned access switching method 100 to the access switching method 300 are based on the same concept and bring the same technical effects. For the specific principles, please refer to the description of the embodiments shown in the above-mentioned access switching method 100 to the access switching method 300 and will not be repeated here.

[0437] The embodiment of the present application also provides a computer-readable storage medium for storing computer software instructions, which, when executed by a communication device, implements the functions of any of the above method embodiments.

[0438] The embodiment of the present application also provides a computer program product for storing computer software instructions, which, when executed by a communication device, implements the functions of any of the above method embodiments.

[0439] The embodiment of the present application also provides a computer program, which, when executed on a computer, implements the functions of any of the above method embodiments.

[0440] The embodiment of the present application also provides a communication system, which includes a terminal device, a first network device, a second network device, and a third network device. In another possible design, the system may also include other devices that interact with the terminal device, the first network device, the second network device, and the third network device.

[0441] The terms "first" and "second" in the specification, claims and drawings of the embodiments of the present application are used to distinguish different objects rather than to describe a specific order. "First", "second" and the like are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second" and the like may explicitly or implicitly include one or more of the features. In the description of this embodiment, unless otherwise specified, "multiple" means two or more.

[0442] In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0443] Mentioning "embodiment" in the embodiments of the present application means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0444] In the embodiments of the present application, "at least one (item)" refers to one or more, "plurality" refers to two or more, and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can represent: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and following associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0445] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete way for easy understanding.

[0446] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a high-density digital video disc (DVD)), or a semiconductor medium (eg, an SSD), etc.

[0447] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An access switching method, characterized in that: The method is applied to a terminal device, and the method comprises: Receive first information, where the first information is used to indicate confirmation information that a first network device configures uplink authorization for the terminal device, and the first network device is a destination network device to be accessed and switched by the terminal device; Determine, according to the first information, a first uplink authorization configured by the first network device for the terminal device, where the first uplink authorization includes a first time domain resource, the first time domain resource is within a first time period, and the first time period is a time period in which the terminal device performs a handover to the first network device; According to the first uplink authorization, switch to the first network device.

2. The method according to claim 1, characterized in that The step of switching to the first network device according to the first uplink authorization includes: receiving a cell switching command from a second network device; Uplink data is sent to the first network device according to the first uplink authorization to access the first network device, and the second network device is a network device currently providing services for the terminal device.

3. The method according to claim 2, characterized in that Before switching to the first network device according to the first uplink authorization, the method further includes: A first indication is received, where the first indication is used to indicate that the first network device has activated the first uplink grant.

4. The method according to claim 1, characterized in that: The step of switching to the first network device according to the first uplink authorization includes: When the first condition is met, sending second information, where the second information is used to request activation of the first uplink authorization, where the first condition is that a signal quality corresponding to the first network device is higher than a signal quality corresponding to the second network device by a first threshold, and the second network device is a network device currently providing services for the terminal device; receiving third information, where the third information is used to indicate that the first network device has activated the first uplink authorization; When a second condition is met, uplink data is sent to the first network device according to the first uplink authorization to access the first network device, and the second condition is that the signal quality corresponding to the first network device is higher than the signal quality corresponding to the second network device by a second threshold, and the second threshold is greater than the first threshold; or When receiving the cell switching command from the second network device, uplink data is sent to the first network device according to the first uplink authorization to access the first network device.

5. The method according to claim 4, characterized in that The method further comprises: receiving the first threshold and the second threshold corresponding to the first network device, where the second threshold is greater than the first threshold; or, Receive the first threshold corresponding to the first network device.

6. The method according to any one of claims 1 to 5, characterized in that: The first information is also used to indicate the first uplink authorization.

7. The method according to any one of claims 1 to 5, characterized in that: The determining a first uplink authorization configured by the first network device for the terminal device includes: receiving fourth information, where the fourth information is used to indicate the first uplink authorization; According to the fourth information, the first uplink authorization configured by the first network device for the terminal device is determined.

8. The method according to any one of claims 1 to 7, characterized in that: The starting time of the first time period is the time when the terminal device sends a measurement report to the second network device, and the ending time is the time when the terminal device accesses the first network device.

9. An access switching method, characterized in that: The method is applied to a third network device, and the method includes: Sending fifth information to the first network device, the fifth information being used to request the first network device to configure an uplink authorization for the terminal device, the fifth information including information for indicating a first time period, the time domain resources in the uplink authorization being within the first time period, the first time period being a time period in which the terminal device performs a handover to the first network device, and the first network device being a destination network device to be accessed and switched by the terminal device; Receive first information from the first network device and send the first information, where the first information is used to indicate that the first network device configures confirmation information of uplink authorization for the terminal device.

10. The method according to claim 9, characterized in that The first information is also used to indicate the first uplink authorization configured by the first network device for the terminal device.

11. The method according to claim 9 or 10, characterized in that: After receiving the first information from the first network device and sending the first information, the method further includes: receiving second information, and sending the second information to the first network device, where the second information is used to request activation of a first uplink authorization configured by the first network device for the terminal device; Receive third information from the first network device and send the third information, where the third information is used to indicate that the first network device has activated the first uplink authorization.

12. The method according to claim 11, characterized in that The method further comprises: Sending a first threshold and a second threshold corresponding to the first network device, where the second threshold is greater than the first threshold; or, Send a first threshold corresponding to the first network device.

13. The method according to any one of claims 9 to 12, characterized in that: The starting time of the first time period is the time when the terminal device sends a measurement report to the second network device, and the ending time is the time when the terminal device accesses the first network device.

14. An access switching method, characterized in that: The method is applied to a first network device, and the method includes: receiving fifth information from a third network device, the fifth information being used to request the first network device to configure an uplink authorization for the terminal device, the fifth information including information for indicating a first time period, the time domain resources in the uplink authorization being within the first time period, the first time period being a time period in which the terminal device performs a handover to the first network device, and the first network device being a destination network device to be accessed and switched by the terminal device; Sending first information to the third network device, where the first information is used to instruct the first network device to configure confirmation information of uplink authorization for the terminal device; According to a first uplink authorization configured for the terminal device, uplink data from the terminal device is received, where the first uplink authorization includes a first time domain resource, and the first time domain resource is located in the first time period.

15. The method according to claim 14, characterized in that The first information is also used to indicate the first uplink authorization.

16. The method according to claim 14, characterized in that Before receiving uplink data from the terminal device according to the first uplink grant configured for the terminal device, the method further includes: Sending fourth information at a first moment, where the fourth information is used to indicate the first uplink authorization; The first time is later than or equal to the start time of the first time period.

17. The method according to any one of claims 14 to 16, characterized in that Before receiving uplink data from the terminal device according to the first uplink grant configured for the terminal device, the method further includes: sending a first indication when a third condition is met, wherein the first indication is used to indicate that the first network device has activated the first uplink authorization; The third condition is that the current time is within the first time period; or, the third condition is: the distance between the terminal device and the first network device is less than or equal to a first preset value, and / or the distance between the terminal device and the second network device is greater than a second preset value, and the second network device is a network device that currently provides services to the terminal device.

18. The method according to any one of claims 14 to 16, characterized in that Before receiving uplink data from the terminal device according to the first uplink grant configured for the terminal device, the method further includes: receiving second information from the third network device, where the second information is used to request activation of the first uplink authorization; Sending third information to the third network device, where the third information is used to indicate that the first network device has activated the first uplink authorization.

19. The method according to any one of claims 14 to 18, characterized in that The starting time of the first time period is the time when the terminal device sends a measurement report to the second network device, and the ending time is the time when the terminal device accesses the first network device. The second network device is the network device currently providing services for the terminal device.

20. A communication device, characterized in that: The communication device comprises a module for executing the method according to any one of claims 1 to 8, or comprises a module for executing the method according to any one of claims 9 to 13, or comprises a module for executing the method according to any one of claims 14 to 19.

21. A communication device, characterized in that: The communication device comprises a processor, wherein the processor is configured to execute the method according to any one of claims 1 to 8, or configured to execute the method according to any one of claims 9 to 13, or configured to execute the method according to any one of claims 14 to 19.

22. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store instructions, which, when executed on a computer, enables the method according to any one of claims 1 to 8 to be executed, or enables the method according to any one of claims 9 to 13 to be executed, or enables the method according to any one of claims 14 to 19 to be executed.

23. A computer program product comprising instructions, characterized in that When it is run on a computer, the method according to any one of claims 1 to 8 is executed, or the method according to any one of claims 9 to 13 is executed, or the method according to any one of claims 14 to 19 is executed.

Images