Communication method and communication device

Abstract

Provided are a communication method and a communication device, comprising: receiving first information from a first network device, a first cell belonging to the first network device, the first cell being a service cell to which a terminal device is currently accessed, the first information comprising a first field used for indicating a candidate cell, or indicating the candidate cell and the service cell to which the terminal equipment is currently accessed; a first cell or a second cell is determined according to the first information and a first rule, the second cell belongs to the candidate cell, and the first rule is used for indicating the corresponding relation between the first field and the candidate cell; or the corresponding relation between the first field and the candidate cell and the corresponding relation between the first field and the service cell currently accessed by the terminal equipment. According to the communication method and the communication device provided by the invention, when the terminal equipment accesses the first cell, the candidate cell or the service cell needing to acquire the timing advance is determined according to the clear indication of the field in the first information, so that preparation is made for flexible switching of the terminal equipment among a plurality of cells.

Description

Technical Field

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

[0002] In a mobile communication system, a terminal device can switch between different cells under the control of a network device. Currently, the network device can instruct the terminal device to initiate a random access request to a neighboring cell based on downlink control signaling. It can be seen that whether the terminal device can efficiently and flexibly switch between cells depends on the clear instructions of the network device.

[0003] Therefore, how to clearly instruct a terminal device to switch to a corresponding cell so as to achieve flexible and efficient switching of the terminal device between multiple cells is a problem that needs to be solved urgently. Summary of the invention

[0004] The present application provides a communication method and a communication device, in which a terminal device can implement flexible switching between multiple cells through explicit instructions from a network device.

[0005] In a first aspect, a communication method is provided, comprising: receiving first information from a first network device, a first cell belonging to the first network device, the first cell being a service cell currently accessed by a terminal device, the first information comprising a first field, the first field being used to indicate a candidate cell, or the first field being used to indicate the candidate cell and the service cell currently accessed by the terminal device; determining the first cell or the second cell according to the first information and a first rule, the second cell belonging to the candidate cell, the second cell belonging to the first network device, or the second cell belonging to the second network device, wherein the first rule is used to indicate a correspondence between the first field and the candidate cell; or the first rule is used to indicate a correspondence between the first field and the candidate cell and a correspondence between the first field and the service cell currently accessed by the terminal device.

[0006] Exemplarily, the first information may be a downlink control indication (DCI) signaling sent by the first network device to the terminal device via a physical downlink control channel (PDCCH), and the DCI includes a field for indicating a candidate cell. For example, the field may be a "cell indicator" field.

[0007] The first rule may be replaced by "corresponding relationship", "associated relationship", etc. The first rule may also be used to indicate the corresponding relationship between the value of the first field and the identifier of the candidate cell; the first rule may also be used to indicate the corresponding relationship between the value of the first field and the physical identifier of the candidate cell; the first rule may also be used to indicate the corresponding relationship between the value of the first field and the logical identifier of the candidate cell, etc.

[0008] It should be understood that when the first rule is used to indicate the correspondence between the first field and the candidate cell, the terminal device can determine the second cell based on the first information and the first rule; when the first rule is used to indicate the correspondence between the first field and the candidate cell and the relationship between the first field and the service cell currently accessed by the terminal device, the terminal device can determine the first cell and / or the second cell based on the first information and the first rule.

[0009] It should be noted that the first rule can be used to indicate the correspondence between the first field and the cell. The cell may include a candidate cell, or may include a candidate cell and a service cell currently accessed by the terminal device. As the terminal device switches, the service cell currently accessed by the terminal device may also change. The cell accessed by the terminal device before the switch can be understood as the service cell currently accessed by the terminal device, and the cell accessed by the terminal device after the switch can be understood as the service cell after the terminal device switches. When the terminal device switches, the service cell after the terminal device switches can also be understood as the service cell currently accessed by the terminal device. The "current" and the "current" before the switch may not be the same moment.

[0010] It should be understood that when the second cell belongs to the first network device, it corresponds to the scenario in which the terminal device in the first network device switches between cells; when the second cell belongs to the second network device, it corresponds to the scenario in which the terminal device between multiple network devices switches between cells.

[0011] Based on the above scheme, when the terminal device accesses the first cell, it can determine the candidate cell or service cell for which timing advance needs to be obtained according to the first information from the first network device of the first cell and the clear indication of the field in the first information, thereby preparing for the flexible switching of the terminal device between multiple cells.

[0012] In combination with the first aspect, in some implementations of the first aspect, the method further includes: sending a random access request message 1 (preamble code) to the first cell or the second cell according to the first information and the first rule.

[0013] Based on the above scheme, the terminal device can determine to send a random access request message 1 (preamble code) to a candidate cell according to the first rule under the clear instruction of the first information, so that the network device can obtain the timing advance of the terminal device in the corresponding cell.

[0014] In combination with the first aspect, in certain implementations of the first aspect, the first cell is a cell configured with random access resource configuration, and the first rule includes: the first field of the first value corresponds to the first cell, and the first fields of other values ​​correspond to different candidate cells; the first information includes the first field of the second value.

[0015] Exemplarily, the random access resource configuration may be a layer 1, layer 2 triggered mobility (L1 / L2 triggeredmobility, LTM) random access resource configuration. The first cell is a cell configured with random access resources, and it can be understood that the first cell can also be used as a candidate cell for the terminal device. After the terminal device switches from the first cell to other cells, the terminal device can also switch back to the first cell from other cells.

[0016] It should be understood that the first field of other values ​​has a one-to-one correspondence with different candidate cells. The terminal device can initiate random access to different candidate cells based on the first field of other values ​​and the first rule. Among them, the candidate cell configuration may include the configuration of the service cell currently accessed by the terminal device, and the corresponding random access resources. That is, when the value of the first field indicates that the terminal device initiates a random access request to the candidate cell, since the candidate cell configuration includes the configuration of the service cell currently accessed by the terminal device, it can also trigger the terminal device to initiate access to the currently accessed service cell. When the first field of the first value (for example, the minimum value of the first field) corresponds to the service cell currently accessed by the terminal device, in addition to the first field of the first value, the first field of other values ​​may also trigger the terminal device to initiate a random access request to the currently accessed service cell.

[0017] It is understandable that the first information may also include a first field with other values, which is not limited in this application.

[0018] Based on the above scheme, the terminal device can determine the candidate cell to be switched to according to the first field with different values, so as to initiate random access to different candidate cells. In addition, since the service cell currently accessed by the terminal device is also configured with random access resource configuration, the terminal device can switch back to the original service cell after switching from the currently accessed service cell to the candidate cell, thereby realizing flexible switching of the terminal device between different cells.

[0019] In combination with the first aspect, in certain implementations of the first aspect, random access is initiated to the first cell or the second cell based on the first information and the first rule, including: sending a random access request message 1 to the first cell based on the first field of the first value and the first rule.

[0020] In combination with the first aspect, in certain implementations of the first aspect, random access is initiated to the first cell or the second cell based on the first information and the first rule, including: sending a random access request message 1 to different candidate cells based on the first field of other values ​​and the first rule.

[0021] Based on the above scheme, when the first field of the first value in the first rule corresponds to the first cell and the first field of the second value corresponds to the second cell, the terminal device can determine the candidate cell to be switched according to the first fields with different values, and send a random access request message 1 to the candidate cell to be switched.

[0022] In combination with the first aspect, in certain implementations of the first aspect, after the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, and the second cell is the service cell after the terminal device is switched, and the first rule is: the first field of the third value corresponds to the first cell, and the first field of the fourth value corresponds to the second cell; wherein the first rule is determined according to the order of the candidate cells configured with random access resource configurations.

[0023] It should be understood that the candidate cell configured with random access resources can be understood as the random access resource configuration of the candidate cell existing in the random access resource configuration of the LTM candidate cell. The first cell accessed by the terminal device before switching is also configured with random access resources, and the random access resource configuration of the first cell also exists in the random access resource configuration of the LTM candidate cell.

[0024] Exemplarily, before and after the terminal device is switched, the order of the candidate cells configured with random access resources is fixed, and therefore, the correspondence between different values ​​and the candidate cells in the first rule is fixed. For example, the first field with a value of '00' corresponds to cell 1 before and after the switch, and the first field with a value of '01' corresponds to cell 2 before and after the switch.

[0025] It should be noted that before switching to the second cell, the terminal device is connected to the first network device of the first cell. Among them, the first cell is a cell configured with random access resource configuration, and it can be understood that the random access resource configuration of the first cell also belongs to the random access resource configuration of the candidate cell. For example, the random access channel (RACH) resources of the first cell exist in the LTM configuration. At this time, the value of the DCI field can be mapped according to the order of the list of candidate cells containing RACH resources in the LTM configuration (the logical identifier of the candidate cells configured with random access resources is in ascending order), that is, the correspondence between the first field and the candidate cell is mapped. Among them, the relationship between the first field and the candidate cell can also be understood as the correspondence between the value of the first field and the candidate cell.

[0026] Exemplarily, when the correspondence between the value of the first field and the candidate cells is mapped according to the order of the candidate cells containing RACH resources in the LTM configuration, during the switching of the terminal device between cells, the value of the first field corresponds to the candidate cells one-to-one, and the correspondence does not change with the switching of the terminal device. Unless the radio resource control (RRC) reconfigures the candidate cell list of the LTM. Among them, the one-to-one correspondence between the value of the first field and the candidate cell can be understood as the one-to-one correspondence between the value of the first field and the physical cell identity (PCI) of the candidate cell.

[0027] In combination with the first aspect, in certain implementations of the first aspect, the first field of the second value corresponds to a second cell, wherein the fourth value is a minimum value.

[0028] It should be understood that after the terminal device switches from the first cell to the second cell, the second cell is the service cell after the terminal device switches. Before and after the terminal device switches, the order of candidate cells configured with random access resources is fixed. Therefore, the correspondence between different values ​​and candidate cells in the first rule is fixed. The candidate cells may include the service cell of the terminal device (for example, the second cell accessed after the terminal device switches), where different values ​​may be understood as values ​​other than the minimum value, and the first field of the minimum value may correspond to the service cell of the terminal device (for example, the first field of the minimum value corresponds to the first cell before the terminal device switches, and may also correspond to the second cell after the terminal device switches). It can be seen that for the service cell of the terminal device, it may correspond to the first field of two values, including the first field of the minimum value, and may also include the first field of the value determined before the switch according to the order of the cell in the candidate cells configured with random access resources.

[0029] Exemplarily, before the terminal device switches, it accesses cell 1, and cell 1 corresponds to the first field with a value of '00', and corresponds to the first field with a value of '01'. Cell 2, as a candidate cell, corresponds to the first field with a value of '10'. After the terminal device switches from cell 1 to cell 2, cell 2 corresponds to the first field with a value of '00', and corresponds to the first field with a value of '10', and cell 1 corresponds to the first field with a value of '01'. It can be seen that after the terminal device switches, cell 2, as the service cell of the terminal device, can correspond to the first field with the minimum value ('00') or the first field with the original value before switching ('10').

[0030] In combination with the first aspect, in certain implementations of the first aspect, after the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the service cell after the terminal device is switched, and the first rule is updated as follows: the first field of the first value corresponds to the second cell, and the first field of the fifth value corresponds to the first cell.

[0031] It should be understood that before the terminal device switches, the first field of the first value corresponds to the first cell; after the terminal device switches, the first field of the first value corresponds to the second cell. The first field of the first value corresponds to the serving cell of the terminal device. Due to the switching of the terminal device, the serving cell of the terminal device is also constantly changing, and the cell corresponding to the first field of the first value will also constantly change with the switching of the terminal device.

[0032] It should be noted that before the terminal device is switched to the second cell, it is connected to the first network device of the first cell. The first cell is a cell configured with a random access resource configuration, and it can be understood that the random access resource configuration of the first cell also belongs to the random access resource configuration of the candidate cell. For example, the random access resource configuration of the first cell also exists in the random access resource configuration of the LTM candidate cell.

[0033] Based on the above scheme, when the terminal device switches from the first cell to the second cell, the first field of the first value is updated from corresponding to the first cell to corresponding to the second cell. At the same time, the first cell is updated to correspond to the first field of the fifth value. The fifth value may be the same as the second value or different from the second value. Whether the fifth value is the same as the second value is related to one of the order of the candidate cells configured with random access resources, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

[0034] In combination with the first aspect, in certain implementations of the first aspect, the updated first rule is related to one of the following: the order of candidate cells configured with random access resource configurations, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

[0035] It should be understood that the updated first rule is determined according to one of the following: the order of candidate cells configured with random access resources, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

[0036] The first order may be an initial default order or an order predefined according to a certain rule. The order of the identifiers of the candidate cells may also be the order of the physical identifiers of the candidate cells.

[0037] It should be noted that, when the updated first rule is related to the order of candidate cells configured with random access resources, the fifth value may be different from the second value; when the updated first rule is related to the first order, the fifth value may be different from the second value; when the updated first rule is related to the correspondence between the first field of the second value, the fifth value is the same as the second value; when the updated first rule is related to the order of the identifiers of the candidate cells, the fifth value may be different from the second value.

[0038] Based on the above scheme, when the terminal device switches between different cells, the first rule can be dynamically updated according to the order of the candidate cells configured with random access resource configuration, the first order, the correspondence between the first field of the second value, the order of the identifiers of the candidate cells, etc. The configuration of the random access resources of the original serving cell accessed by the terminal device also belongs to the configuration of the random access resources of the candidate cell, so that the terminal device can flexibly switch back and forth between different candidate cells.

[0039] In combination with the first aspect, in certain implementations of the first aspect, the order of the candidate cells configured with random access resources is determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

[0040] It can also be understood that the order of the candidate cells configured with the random access resource configuration is related to the ascending order of the logical identifiers of the candidate cells configured with the random access resource.

[0041] In combination with the first aspect, in certain implementations of the first aspect, when the first field of the first value corresponds to a service cell to which the terminal device is currently connected, or corresponds to a service cell after the terminal device has switched, the first value is a minimum value.

[0042] It should be understood that when the first field of the first value corresponds to the first cell accessed by the terminal device before switching, or the second cell after the terminal device switches, the first value is the minimum value. The first value as the minimum value may refer to the minimum value of an N-bit binary number, where N is greater than or equal to 1, or may refer to the minimum value of a decimal number. For example, the first value may be '0', '00', or '000'.

[0043] Based on the above scheme, the first rule can preset the first field of the minimum value to correspond to the service cell of the terminal device. As the service cell of the terminal device changes, the cell corresponding to the first field of the minimum value will also change, and the cells corresponding to the first fields of other values ​​may also change accordingly.

[0044] In combination with the first aspect, in certain implementations of the first aspect, the first information includes a second field, and the second field is used to indicate whether the terminal device triggers sending a random access request message 1 to the first cell.

[0045] It should be understood that the first information may also include a second field for indicating whether the terminal device triggers sending a random access request message 1 to the currently accessed serving cell. The second field may be a newly added 1 bit in the first information.

[0046] Optionally, the second field may be enabled or disabled in the RRC configuration DCI format.

[0047] Based on the above scheme, the terminal device can be displayed and instructed to switch to a candidate cell, or trigger access to the current service cell through the second field in the first information, so that the terminal device can flexibly switch back and forth between different cells.

[0048] In combination with the first aspect, in certain implementations of the first aspect, when the value of the second field is the sixth value, the first field is a fill field, and the second cell is determined according to the first information and the first rule, including: determining to send a random access request message 1 to the first cell according to the second field in the first information.

[0049] Exemplarily, when the sixth value is 1, the second field is used to indicate that the terminal device can trigger random access to the currently accessed serving cell (first cell). At this time, the value of the first field can be regarded as meaningless, and the terminal device can ignore the first field, or regard the first field as a filler bit. The PDCCH used to transmit the first information is only used to indicate the random access resources of the currently accessed serving cell (first cell).

[0050] In combination with the first aspect, in certain implementations of the first aspect, when the value of the second field is the seventh value, before determining the second cell based on the first information and the first rule, the method also includes: determining not to send a random access request message 1 to the first cell based on the second field in the first information.

[0051] Exemplarily, when the seventh value is 0, the second field is used to indicate that the terminal device cannot trigger random access to the currently accessed serving cell (first cell). At this time, the currently accessed serving cell does not belong to the candidate cell, and the PDCCH used to transmit the first information is only used to indicate the random access resources of the candidate cell. The value of the first field corresponds to the candidate cell containing the RACH.

[0052] In a second aspect, a communication method is provided, including: a first network device sends first information to a terminal device, the first information being used to instruct the terminal device to determine a first cell or a second cell according to a first rule; wherein the first cell belongs to the first network device, the first cell is a service cell currently accessed by the terminal device, and the first information includes a first field, the first field being used to indicate a candidate cell; or the first field is used to indicate the candidate cell and the service cell currently accessed by the terminal device, the second cell belongs to the candidate cell, the second cell belongs to the first network device, or the second cell belongs to the second network device, the first rule is used to indicate a correspondence between the first field and the candidate cell, or the first rule is used to indicate a correspondence between the first field and the candidate cell and a correspondence between the first field and the service cell currently accessed by the terminal device.

[0053] In combination with the second aspect, in certain implementations of the second aspect, the first cell is a cell configured with random access resource configuration, and the first rule includes: the first field of the first value corresponds to the first cell, and the first fields of other values ​​correspond to different candidate cells; the first information includes the first field of the second value.

[0054] In combination with the second aspect, in certain implementations of the second aspect, after the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, and the second cell is the service cell after the terminal device is switched, and the first rule is: the first field of the third value corresponds to the first cell, and the first field of the fourth value corresponds to the second cell; wherein the first rule is determined according to the order of the candidate cells configured with random access resource configurations.

[0055] In combination with the second aspect, in certain implementations of the second aspect, the first field of the second value corresponds to a second cell, wherein the fourth value is a minimum value.

[0056] In combination with the second aspect, in certain implementations of the second aspect, after the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the service cell after the terminal device is switched, and the first rule is updated as follows: the first field of the first value corresponds to the second cell, and the first field of the fifth value corresponds to the first cell.

[0057] In combination with the second aspect, in certain implementations of the second aspect, the updated first rule is related to one of the following: the order of candidate cells configured with random access resource configurations, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

[0058] In combination with the second aspect, in certain implementations of the second aspect, the order of the candidate cells configured with random access resources is determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

[0059] In combination with the second aspect, in certain implementations of the second aspect, when the first field of the first value corresponds to a service cell to which the terminal device is currently connected, or corresponds to a service cell after the terminal device has switched, the first value is a minimum value.

[0060] In combination with the second aspect, in some implementations of the second aspect, the first information includes a second field, and the second field is used to indicate whether the terminal device triggers sending a random access request message 1 to the first cell.

[0061] In combination with the second aspect, in some implementations of the second aspect, when the value of the second field is the sixth value, the first field is a padding field.

[0062] In a third aspect, a communication device is provided, comprising: a transceiver unit, configured to receive first information from a first network device, a first cell belonging to the first network device, the first cell being a service cell currently accessed by the communication device, the first information comprising a first field, the first field being used to indicate a candidate cell, or the first field being used to indicate the candidate cell and the service cell currently accessed by the communication device; a processing unit, configured to determine the first cell or the second cell according to the first information and a first rule, the second cell belonging to the candidate cell, the second cell belonging to the first network device, or the second cell belonging to the second network device, wherein the first rule is used to indicate a correspondence between the first field and the candidate cell; or the first rule is used to indicate a correspondence between the first field and the candidate cell and a correspondence between the first field and the service cell currently accessed by the communication device.

[0063] In combination with the third aspect, in certain implementations of the third aspect, the processing unit is further used to send a random access request message 1 to the first cell or the second cell according to the first information and the first rule.

[0064] In combination with the third aspect, in certain implementations of the third aspect, the first cell is a cell configured with random access resource configuration, and the first rule includes: the first field of the first value corresponds to the first cell, and the first fields of other values ​​correspond to different candidate cells; the first information includes the first field of the second value.

[0065] In combination with the third aspect, in certain implementations of the third aspect, the processing unit is specifically used to send a random access request message 1 to the first cell according to the first field of the first value and the first rule.

[0066] In combination with the third aspect, in certain implementations of the third aspect, the processing unit is specifically used to send a random access request message 1 to different candidate cells according to the first field of other values ​​and the first rule.

[0067] In combination with the third aspect, in certain implementations of the third aspect, after the communication device switches from the first cell to the second cell, the first cell belongs to the candidate cell, and the second cell is the service cell after the communication device is switched, and the first rule is: the first field of the third value corresponds to the first cell, and the first field of the fourth value corresponds to the second cell; wherein the first rule is determined according to the order of the candidate cells configured with random access resource configurations.

[0068] In combination with the third aspect, in certain implementations of the third aspect, the first field of the second value corresponds to a second cell, wherein the fourth value is a minimum value.

[0069] In combination with the third aspect, in certain implementations of the third aspect, after the communication device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the service cell after the communication device is switched, and the first rule is updated to: the first field of the first value corresponds to the second cell, and the first field of the fifth value corresponds to the first cell.

[0070] In combination with the third aspect, in certain implementations of the third aspect, the updated first rule is related to one of the following: the order of candidate cells configured with random access resource configurations, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

[0071] In combination with the third aspect, in certain implementations of the third aspect, the order of the candidate cells configured with random access resources is determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

[0072] In combination with the third aspect, in certain implementations of the third aspect, when the first field of the first value corresponds to a service cell to which the communication device is currently connected, or corresponds to a service cell after the communication device has switched, the first value is a minimum value.

[0073] In combination with the third aspect, in certain implementations of the third aspect, the first information includes a second field, and the second field is used to indicate whether the communication device triggers sending a random access request message 1 to the first cell.

[0074] In combination with the third aspect, in certain implementations of the third aspect, when the value of the second field is the sixth value, the first field is a fill field, and the processing unit is specifically used to determine to send a random access request message 1 to the first cell based on the second field in the first information.

[0075] In combination with the third aspect, in certain implementations of the third aspect, when the value of the second field is the seventh value, before determining the second cell based on the first information and the first rule, the processing unit is also used to determine not to send a random access request message 1 to the first cell based on the second field in the first information.

[0076] In a fourth aspect, a communication device is provided, comprising: a transceiver unit, configured to send first information to a terminal device, the first information being used to instruct the terminal device to determine a first cell or a second cell according to a first rule; wherein the first cell belongs to the communication device, the first cell is a service cell currently accessed by the terminal device, and the first information comprises a first field, the first field being used to indicate a candidate cell; or the first field being used to indicate the candidate cell and the service cell currently accessed by the terminal device, the second cell belonging to the candidate cell, the second cell belonging to the communication device, or the second cell belonging to a second network device, the first rule being used to indicate a correspondence between the first field and the candidate cell, or the first rule being used to indicate a correspondence between the first field and the candidate cell and a correspondence between the first field and the service cell currently accessed by the terminal device.

[0077] In combination with the fourth aspect, in certain implementations of the fourth aspect, the first cell is a cell configured with random access resource configuration, and the first rule includes: the first field of the first value corresponds to the first cell, and the first fields of other values ​​correspond to different candidate cells; the first information includes the first field of the second value.

[0078] In combination with the fourth aspect, in certain implementations of the fourth aspect, after the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, and the second cell is the service cell after the terminal device is switched, and the first rule is: the first field of the third value corresponds to the first cell, and the first field of the fourth value corresponds to the second cell; wherein the first rule is determined according to the order of the candidate cells configured with random access resource configurations.

[0079] In combination with the fourth aspect, in certain implementations of the fourth aspect, the first field of the second value corresponds to the second cell, wherein the fourth value is a minimum value.

[0080] In combination with the fourth aspect, in certain implementations of the fourth aspect, after the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the service cell after the terminal device is switched, and the first rule is updated to: the first field of the first value corresponds to the second cell, and the first field of the fifth value corresponds to the first cell.

[0081] In combination with the fourth aspect, in certain implementations of the fourth aspect, the updated first rule is related to one of the following: the order of candidate cells configured with random access resource configurations, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

[0082] In combination with the fourth aspect, in certain implementations of the fourth aspect, the order of the candidate cells configured with random access resources is determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

[0083] In combination with the fourth aspect, in certain implementations of the fourth aspect, when the first field of the first value corresponds to a service cell to which the terminal device is currently connected, or corresponds to a service cell after the terminal device is switched, the first value is a minimum value.

[0084] In combination with the fourth aspect, in certain implementations of the fourth aspect, the first information includes a second field, and the second field is used to indicate whether the terminal device triggers sending a random access request message 1 to the first cell.

[0085] In combination with the fourth aspect, in certain implementations of the fourth aspect, when the value of the second field is the sixth value, the first field is a padding field.

[0086] In a fifth aspect, a communication device is provided, comprising: a processor coupled to a memory, the memory being used to store a computer program, the processor being used to run the computer program, so that the communication device executes the method in the above-mentioned first aspect and any possible implementation thereof.

[0087] In a sixth aspect, a communication device is provided, comprising: a processor coupled to a memory, the memory being used to store a computer program, the processor being used to run the computer program, so that the communication device executes the method in the above-mentioned second aspect and any possible implementation thereof.

[0088] In the seventh aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a computer, the computer executes the communication method that can be implemented in the first aspect and any one of the first aspect, or the second aspect and any one of the second aspect.

[0089] In an eighth aspect, a computer program product comprising instructions is provided. When the computer program product is run on a computer, the computer executes any communication method that can be implemented in the first aspect and any one of the first aspect, or the second aspect and any one of the second aspect.

[0090] In the ninth aspect, a chip is provided, which includes a processor and a data interface, and the processor reads instructions stored in a memory through the data interface to execute any communication method that can be implemented in the first aspect and any one of the first aspects, or the second aspect and any one of the second aspects.

[0091] In combination with the ninth aspect, in one possible implementation, the processor is coupled to the memory via an interface.

[0092] In combination with the ninth aspect, in a possible implementation, the chip system also includes a memory, in which a computer program or computer instructions are stored. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] Figure 1 This is a schematic diagram of a scenario provided in an embodiment of the present application.

[0094] Figure 2 It is a schematic flow chart of a communication method provided in an embodiment of the present application.

[0095] Figure 3 It is a corresponding relationship diagram provided in an embodiment of the present application.

[0096] Figure 4 It is a corresponding relationship diagram provided in an embodiment of the present application.

[0097] Figure 5 It is a corresponding relationship diagram provided in an embodiment of the present application.

[0098] Figure 6 It is a schematic diagram of the field structure of a first information provided in an embodiment of the present application.

[0099] Figure 7It is a schematic block diagram of a communication device of the present application.

[0100] Figure 8 It is a schematic block diagram of a terminal device of the present application.

[0101] Fig. 9 It is a schematic block diagram of another communication device of the present application.

[0102] Fig.10 It is a schematic block diagram of a network device of the present application. DETAILED DESCRIPTION

[0103] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0104] The technical solutions of the embodiments of the present application can be applied to various communication systems, for example: global system for mobile communications (GSM) system, code division multiple access (CDMA) system, wideband code division multiple access (WCDMA) system, general packet radio service (GPRS), long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication system, future fifth generation (5G) system or new radio (NR), etc.

[0105] The terminal equipment (UE) involved in the embodiments of the present application may include various handheld devices with wireless communication functions, vehicle-mounted devices, wearable devices, computing devices, or other processing devices connected to a wireless modem. The terminal equipment may be a mobile station (MS), a subscriber unit, a cellular phone, a smart phone, a wireless data card, a personal digital assistant (PDA), a tablet computer, a wireless modem, a handheld device (handset), a laptop computer, a machine type communication (MTC) terminal, etc., and the embodiments of the present application are not limited to this.

[0106] The network device in the embodiment of the present application may also be referred to as an access network device, and the network device may be a base station (base transceiver station, BTS) in a global system for mobile communications (GSM) system or code division multiple access (code division multiple access, CDMA), or a base station (NodeB, NB) in a wideband code division multiple access (WCDMA) system, or an evolved NodeB (eNB or eNodeB) in an LTE system, or a wireless controller in a cloud radio access network (CRAN) scenario, or the network device may be a relay station, an access point, a vehicle-mounted device, a wearable device, and a network device in a future 5G network or a network device in a future evolved PLMN network, for example, a transmission point (TRP or TP) in an NR system, a base station (gNB) in an NR system, one or a group (including multiple antenna panels) of antenna panels of a base station in a 5G system, etc. The embodiment of the present application is not particularly limited to this.

[0107] The embodiments of the present application do not particularly limit the specific structure of the execution subject of the method provided by the embodiments of the present application. As long as it is possible to communicate according to the method provided by the embodiments of the present application by running a program that records the code of the method provided by the embodiments of the present application, for example, the execution subject of the method provided by the embodiments of the present application may be a terminal device or a network device, or a functional module in the terminal device or the network device that can call and execute the program.

[0108] In addition, various aspects or features of the present application can be implemented as methods, devices or products using standard programming and / or engineering techniques. The term "product" used in this application covers computer programs that can be accessed from any computer-readable device, carrier or medium. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disks, floppy disks or tapes, etc.), optical disks (e.g., compact discs (CDs), digital versatile discs (DVDs), etc.), smart cards and flash memory devices (e.g., erasable programmable read-only memory (EPROM), cards, sticks or key drives, etc.). In addition, the various storage media described herein may represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media capable of storing, containing and / or carrying instructions and / or data.

[0109] The embodiments of the present application do not particularly limit the specific structure of the execution subject of the method provided by the embodiments of the present application. As long as it is possible to communicate according to the method provided by the embodiments of the present application by running a program that records the code of the method provided by the embodiments of the present application, for example, the execution subject of the method provided by the embodiments of the present application may be a terminal device or a network device, or a functional module in the terminal device or the network device that can call and execute the program.

[0110] The following introduces the technical terms involved in the embodiments of the present application.

[0111] Beam: A beam is a communication resource. A beam can be a wide beam, a narrow beam, or other types of beams. The technology for forming a beam can be beamforming technology or other technical means. Beamforming technology can be specifically digital beamforming technology, analog beamforming technology, and hybrid digital / analog beamforming technology. Different beams can be considered as different resources. The same information or different information can be sent through different beams. Optionally, multiple beams with the same or similar communication characteristics can be regarded as a beam. A beam can include one or more antenna ports for transmitting data channels, control channels, and detection signals. For example, a transmit beam can refer to the distribution of signal strength in different directions in space after the signal is transmitted by the antenna, and a receive beam can refer to the distribution of signal strength of wireless signals received from the antenna in different directions in space. It can be understood that one or more antenna ports that form a beam can also be regarded as an antenna port set.

[0112] When using low-frequency or medium-frequency bands, signals can be sent omnidirectionally or through a wider angle. When using high-frequency bands, thanks to the smaller carrier wavelength of the high-frequency communication system, an antenna array consisting of many antenna elements can be arranged at the transmitting and receiving ends. The transmitting end sends the signal with a certain beamforming weight so that the transmitted signal forms a beam with spatial directivity. At the same time, the receiving end uses an antenna array with a certain beamforming weight for reception, which can increase the received power of the signal at the receiving end and combat path loss.

[0113] Reference Signal: According to the Long Term Evolution LTE / NR protocol, at the physical layer, uplink communication includes the transmission of uplink physical channels and uplink signals. Uplink physical channels include random access channel (PRACH), uplink control channel (PUCCH), uplink data channel (PUSCH), etc. Uplink signals include channel sounding signal SRS, uplink control channel demodulation reference signal (PUCCH de-modulation reference signal, PUCCH-DMRS), uplink data channel demodulation reference signal PUSCH-DMRS, uplink phase noise tracking signal (PTRS), uplink positioning signal (uplink positioning RS), etc. Downlink communication includes the transmission of downlink physical channels and downlink signals. The downlink physical channels include physical broadcast channel (PBCH), physical downlink control channel (PDCCH), physical downlink shared channel (PDSCH), etc. The downlink signals include primary synchronization signal (PSS) / secondary synchronization signal (SSS), downlink control channel demodulation reference signal PDCCH-DMRS, downlink data channel demodulation reference signal PDSCH-DMRS, phase noise tracking signal PTRS, channel status information reference signal (CSI-RS), cell signal (CRS) (NR does not have), time / frequency tracking reference signal (TRS) (LTE does not have), LTE / NR positioning signal (positioning RS), etc.

[0114] Timing Advance (TA): Timing advance is used for UE uplink transmission, which means that the UE sends data packets in advance according to the corresponding instructions. The timing advance command (TAC) is sent by the base station to the UE to inform the UE of the time size of the timing advance. An important feature of uplink transmission is that different UEs have orthogonal multiple access in time and frequency, that is, the uplink transmissions of different UEs in the same cell do not interfere with each other. In order to ensure the orthogonality of uplink transmission and avoid interference within the cell, TRP requires that the time when the signals from different UEs in the same subframe but different frequency domain resources arrive at the TRP is basically aligned. As long as the TRP receives the uplink data sent by the UE within the cyclic prefix (CP) range, it can correctly decode the uplink data. Therefore, uplink synchronization requires that the time when the signals from different UEs in the same subframe arrive at the TRP falls within the CP. From the UE side, TA is essentially a negative offset between the start time of receiving the downlink subframe and the time of transmitting the uplink subframe. TRP can control the time when the uplink signals from different UEs arrive at the TRP by properly controlling the offset of each UE. For UEs that are farther away from the TRP, due to the larger transmission delay, they need to send uplink data earlier than UEs that are closer to the TRP.

[0115] Figure 1 A schematic block diagram of a wireless communication system 100 according to an embodiment of the present application is shown. The wireless communication system 100 includes at least two cells, for example, a serving cell belonging to a first network device 110 and a candidate cell belonging to a second network device 120. When a terminal device 130 moves from a serving cell to a candidate cell, a handover may occur, that is, switching from a serving cell to a candidate cell.

[0116] It should be noted that when the terminal device switches to a candidate cell, the candidate cell can be understood as a new service cell, and the original service cell can be understood as a new candidate cell.

[0117] It should be understood that the candidate cell may be a neighboring cell of the serving cell. In the embodiments of the present application, "first", "second", "third", "fourth", etc. are only for distinction, and the first, second, third, and fourth are not intended to limit the embodiments of the present application.

[0118] It should be understood that in the embodiment of the present application, a network device may have one or more cells. The serving cell and the candidate cell may also belong to the same network device, that is, the first network device and the second network device may be the same network device. In this case, the terminal device performs a handover within the network device.

[0119] Optionally, the serving cell and the candidate cell may also belong to different network devices, that is, the first network device and the second network device may be different network devices. In this case, the terminal device performs a handover between network devices.

[0120] It should be noted that the communication method provided in the embodiment of the present application can take a single network device and a terminal device as an example, and the network device can transmit data or control signaling to the terminal device.

[0121] Specifically, based on the configuration information of the network device, the terminal device can report the measurement result of the reference signal for switching the service beam of the terminal. Each cell (including the serving cell and the candidate cell) can be configured with multiple carriers.

[0122] like Figure 1 As shown, the current terminal device 130 is controlled by the first network device of the service cell, and the first network device controls the terminal device to switch to the candidate cell by sending a switching message. At present, the first network device triggers the random access channel (RACH) initiated by the terminal device to the candidate cell through the downlink control channel (physical downlink control channel, PDCCH). This method requires the use of downlink control indication (DCI) signaling. This function is usually applicable to uplink asynchronous scenarios, that is, the terminal device can receive the downlink normally, but the uplink transmission timing has failed or lost. The network device requires the terminal device to re-acquire the timing advance (timing alignment, TA) through the random access process for transmitting uplink data.

[0123] It should be noted that when DCI signaling is currently used to trigger a terminal device to initiate a RACH to a candidate cell, the network device needs to carry the DCI signaling in format 01 in the PDCCH.

[0124] Optionally, the DCI signaling may include the following fields: preamble index (random access preamble index); normal uplink carrier or supplementary uplink carrier (uplink indicator / supplement uplink indicator); synchronization / broadcasting signal index (synchronization signal index / physical broadcasting channel index); mask index (physical random access channel mask index); reserved bits. Part of the reserved bits may be used to indicate candidate cells for random access.

[0125] Based on this, the terminal device can continue to switch to other candidate cells without receiving a radio resource control (RRC) reconfiguration command after switching to a new cell. Other candidate cells can also be the original serving cell, which means that after the terminal device switches to a new cell, it can switch back to the original serving cell based on the switching command issued by the new cell without reconfiguration.

[0126] However, if the reserved 2 or 3 bits in the DCI signaling are used to indicate the candidate cell, the correspondence between the field used to indicate the candidate cell and the candidate cell needs to be clearly defined. Otherwise, the terminal device will not be able to determine which cell's random access resources will be used to send the random access request message 1, thereby affecting the switching process of the terminal device.

[0127] In view of the above problems, an embodiment of the present application provides a communication method and a communication device, which clearly indicate the corresponding relationship between the field for indicating the candidate cell and the candidate cell, and clearly indicate how the DCI instructs the terminal device to initiate random access to the candidate cell, thereby improving the switching efficiency of the terminal device.

[0128] In the following, for the sake of ease of understanding and explanation, the execution process and actions of the communication method in the present application in the communication system are described as an example rather than a limitation.

[0129] like Figure 2 As shown, a schematic flow chart of a communication method provided in an embodiment of the present application is shown. Figure 2 The method shown can be applied to Figure 1 In the communication system shown in FIG. Figure 2 The illustrated method 200 includes:

[0130] S201, a terminal device receives first information, and correspondingly, a first network device sends first information.

[0131] It should be noted that the first cell belongs to the first network device, and the first cell is a serving cell currently accessed by the terminal device. With the switching of the terminal device, the serving cell currently accessed by the terminal device may change.

[0132] Exemplarily, the first information may be DCI sent by the first network device to the terminal device via the PDCCH, and the DCI includes a field for indicating the candidate cell. For example, the field may be a "cell indicator" field.

[0133] In one implementation, the first information includes a first field, where the first field is used to indicate a candidate cell, or the first field is used to indicate a candidate cell and a serving cell currently accessed by the terminal device.

[0134] Exemplarily, the first field is a "cell indicator" field. When the serving cell currently accessed by the terminal device is the first cell and the candidate cell is the second cell, the first field can be used to indicate the second cell, or to indicate the first cell and the second cell.

[0135] It should be understood that the embodiment of the present application does not limit the number of bits in the first field, which can be 2 bits or 3 bits. C represents the number of candidate cells configured with RACH resources, and "+1" represents the inclusion of the serving cell, that is, N is the logarithm of (C+1) with base 2, and then the integer is rounded upward.

[0136] S202, the terminal device determines the first cell or the second cell according to the first information and the first rule.

[0137] It should be noted that the second cell belongs to the candidate cell, the second cell belongs to the first network device, or the second cell belongs to the second network device. The second cell and the first cell may be neighboring cells of each other. If the terminal device switches from the first cell to the second cell, the second cell may be understood as the serving cell after the terminal device switches.

[0138] It should be understood that when the second cell belongs to the first network device, it corresponds to the scenario in which the terminal device in the first network device switches between cells; when the second cell belongs to the second network device, it corresponds to the scenario in which the terminal device between multiple network devices switches between cells.

[0139] It should be understood that the first rule is used to indicate the correspondence between the first field and the candidate cell; or the first rule is used to indicate the correspondence between the first field and the candidate cell and the correspondence between the first field and the serving cell currently accessed by the terminal device. The first rule can be replaced by "correspondence", "association", etc.

[0140] It should be understood that the first rule can also be used to indicate the correspondence between the value of the first field and the identifier of the candidate cell; the first rule can also be used to indicate the correspondence between the value of the first field and the physical identifier of the candidate cell; the first rule can also be used to indicate the correspondence between the value of the first field and the logical identifier of the candidate cell, etc.

[0141] It should be understood that the network device can configure at least one cell or cell group for the terminal device as a candidate cell to be switched by the terminal device. At the same time, the network device configures identifiers for these cells or cell groups, which can be understood as logical identifiers, and can be different from the cell identifier or the cell physical identifier (PCI). The service cell accessed by the terminal device can also be used as a candidate cell and is associated with the identifier of the candidate cell. Generally speaking, the service cell configuration as a candidate cell can be used in scenarios where the terminal device continuously switches between cells, that is, after the terminal device switches from the currently accessed service cell to other candidate cells, it can switch back to the original service cell without reconfiguration.

[0142] Exemplarily, when the first field is used to indicate a candidate cell, the first rule is used to indicate the correspondence between the first field and the candidate cell; when the first field is used to indicate the candidate cell and the service cell currently accessed by the terminal device, the first rule is used to indicate the correspondence between the first field and the candidate cell and the correspondence between the first field and the service cell currently accessed by the terminal device.

[0143] It should be understood that when the first rule is used to indicate the correspondence between the first field and the candidate cell, the terminal device can determine the second cell based on the first information and the first rule; when the first rule is used to indicate the correspondence between the first field and the candidate cell and the relationship between the first field and the service cell currently accessed by the terminal device, the terminal device can determine the first cell and / or the second cell based on the first information and the first rule.

[0144] Furthermore, the terminal device may send a random access request message 1 to the first cell or the second cell according to the first information and the first rule.

[0145] Specifically, the terminal device may send a random access request message 1 to the first cell or the second cell according to the value of the first field and the first rule. Alternatively, the terminal device may send a random access request message 1 to the first cell or the second cell according to the value of the first field and the association relationship. Alternatively, the terminal device may send a random access request message 1 to the first cell or the second cell according to the value of the first field and the corresponding relationship.

[0146] That is to say, to which cell the terminal device sends the random access request message 1 is related to the value of the first field and the correspondence between the value of the first field and the identifier of the cell.

[0147] In one implementation, the first cell is a cell configured with random access resources, the first rule includes: a first field with a first value corresponds to the first cell, and first fields with other values ​​correspond to different candidate cells. The first information includes a first field with a second value.

[0148] Specifically, the terminal device may send a random access request message 1 to the first cell according to the first field of the first value and the first rule. The terminal device may send a random access request message 1 to the second cell according to the first field of the second value and the first rule.

[0149] Exemplarily, the random access resource configuration of the candidate cell may be a layer 1, layer 2 triggered mobility (L1 / L2triggered mobility, LTM) candidate cell resource configuration. The first cell is a cell configured with random access resources, and it can be understood that the first cell can also be used as a candidate cell for the terminal device. After the terminal device switches from the first cell to other cells, the terminal device can also switch back to the first cell from other cells.

[0150] It should be understood that the first field with other values ​​has a one-to-one correspondence with different candidate cells.

[0151] The terminal device can initiate random access to different candidate cells based on the first field with other values ​​and the first rule.

[0152] It should be noted that, based on the first field including the second value in the first information, the terminal device can determine that the second cell is a candidate cell according to the first field of the second value in the first information and the first rule.

[0153] It is understandable that the first information may also include a first field with other values, which is not limited in this application.

[0154] It should be noted that the first rule can be used to indicate the correspondence between the first field and the cell. The cell may include a candidate cell, or may include a candidate cell and a service cell currently accessed by the terminal device. As the terminal device switches, the service cell currently accessed by the terminal device may also change. The cell accessed by the terminal device before the switch can be understood as the service cell currently accessed by the terminal device, and the cell accessed by the terminal device after the switch can be understood as the service cell after the terminal device switches. When the terminal device switches, the service cell after the terminal device switches can also be understood as the service cell currently accessed by the terminal device. The "current" and the "current" before the switch may not be the same moment.

[0155] It should be understood that the correspondence between the first field and the cell may be fixed or may change flexibly as the terminal device switches between different cells. In other words, the first rule may be fixed or may be dynamically updated.

[0156] Based on this, several possible situations of the first rule are introduced below.

[0157] Method 1: The first rule is fixed.

[0158] It should be noted that the fixed first rule can be understood as the corresponding relationship between the value of the first field and the cell is fixed. The cell may include a candidate cell and a serving cell currently accessed by the terminal device.

[0159] It should be understood that the fixity of the first rule is relative, and not all the corresponding relationships between the first field and the cell are fixed. At least the corresponding relationships between the first field and the cell except the minimum value are fixed.

[0160] In an embodiment of the present application, a terminal device receives first information from a first network device of a first cell, the first information includes a first field, the first field is used to indicate a candidate cell; or the first field is used to indicate a candidate cell and a serving cell currently accessed by the terminal device; the terminal device determines the first cell or the second cell according to the first information and the first rule, wherein the first cell is the serving cell currently accessed by the terminal device, the second cell is a candidate cell, and the first rule is used to indicate the correspondence between the first field and the candidate cell; or the first rule is used to indicate the correspondence between the first field and the candidate cell and the correspondence between the first field and the serving cell currently accessed by the terminal device. Specifically, the first field of the first value corresponds to the first cell (the serving cell currently accessed by the terminal device), and the first field of the second value corresponds to the second cell (one of the candidate cells of the terminal device). The terminal device determines the second cell according to the first field of the second value in the first information and the first rule, and sends a random access request message 1 to the second cell. After the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, and the second cell is the serving cell after the terminal device switches. The first rule after switching is: the first field of the third value corresponds to the first cell, and the first field of the fourth value corresponds to the second cell. The first rule is determined according to the order of candidate cells configured with random access resources.

[0161] It should be understood that the candidate cell configured with random access resources can be understood as the random access resource configuration of the candidate cell existing in the random access resource configuration of the LTM candidate cell. The first cell accessed by the terminal device before switching is also configured with random access resources, and the random access resource configuration of the first cell also exists in the random access resource configuration of the LTM candidate cell.

[0162] It should be noted that the order of the candidate cells configured with random access resources is determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

[0163] It can be seen that the order of candidate cells configured with random access resources before and after the terminal device is switched is fixed, so the correspondence between different values ​​and candidate cells in the first rule is fixed. For example, the first field with a value of 00 corresponds to cell 1 before and after the switch, and the first field with a value of 01 corresponds to cell 2 before and after the switch.

[0164] It should be noted that before the terminal device switches to the second cell, it is connected to the first network device of the first cell. Among them, the first cell is a cell configured with random access resource configuration, and it can be understood that the configuration of random access resources of the first cell also belongs to the random access resource configuration of the candidate cell. For example, the RACH resources of the first cell exist in the LTM configuration. At this time, the value of the DCI field can be mapped according to the order of the list of candidate cells containing RACH resources in the LTM configuration (the logical identifier of the candidate cells configured with random access resources is in ascending order), that is, the correspondence between the first field and the candidate cell is mapped. Among them, the relationship between the first field and the candidate cell can also be understood as the correspondence between the value of the first field and the candidate cell.

[0165] Exemplarily, when the correspondence between the value of the first field and the candidate cells is mapped according to the order of the candidate cells containing RACH resources in the LTM configuration, during the switching of the terminal device between cells, the value of the first field corresponds to the candidate cell one-to-one, and the correspondence does not change with the switching of the terminal device. Unless the RRC reconfigures the candidate cell list of LTM. Among them, the one-to-one correspondence between the value of the first field and the candidate cell can be understood as the one-to-one correspondence between the value of the first field and the physical cell identity (PCI) of the candidate cell.

[0166] For example, in the RRC configuration signaling, the LTM configuration includes the following correspondence:

[0167] LTM-candidate Cell ID = 0, corresponding to Physical cell ID = 538 (with RACH configuration)

[0168] LTM-candidate Cell ID = 1, corresponding to Physical cell ID = 1002 (with RACH configuration)

[0169] LTM-candidate Cell ID = 2, corresponding to Physical cell ID = 123 (current serving cell, with RACH configuration)

[0170] LTM-candidate Cell ID = 3, corresponding to Physical cell ID = 356

[0171] LTM-candidate Cell ID = 4, corresponding to Physical cell ID = 432

[0172] LTM-candidate Cell ID = 5, corresponding to Physical cell ID = 974

[0173] LTM-candidate Cell ID = 6, corresponding to Physical cell ID = 736 (with RACH configuration)

[0174] LTM-candidate Cell ID = 7, corresponding to Physical cell ID = 176

[0175] Based on the list order of candidate cells containing RACH resources in the above LTM configuration (the logical identifiers of candidate cells configured with random access resources are in ascending order), mapped to the first field with different values, we can get:

[0176] LTM-candidate Cell ID = 0, corresponding to Physical cell ID = 538, corresponding to '00'

[0177] LTM-candidate Cell ID = 1, corresponding to Physical cell ID = 1002, corresponding to '01'

[0178] LTM-candidate Cell ID = 2, corresponding to Physical cell ID = 123, corresponding to '10'

[0179] LTM-candidate Cell ID = 6, corresponding to Physical cell ID = 736, corresponding to '11'

[0180] Candidate cell 538 corresponds to the first field with a value of '00'; candidate cell 1002 corresponds to the first field with a value of '01'; candidate cell 123 corresponds to the first field with a value of '10'; and candidate cell 736 corresponds to the first field with a value of '11'.

[0181] It can be seen that the physical identifier of the candidate cell can be corresponded to the first field with different values. When the terminal device receives the first information including the first field, the candidate cell to be switched can be determined.

[0182] It should be noted that the candidate cells in the LTM configuration may also not contain RACH resources, for example, candidate cell 356, candidate cell 432, candidate cell 974 and candidate cell 176. Candidate cells without RACH resources may also occupy the first field of the corresponding value, but the first field of the corresponding value corresponding to the candidate cell without RACH resources may be ignored by the terminal device, or will not be used to indicate the candidate cell to which the terminal device is to switch.

[0183] Exemplarily, if the first cell is candidate cell 123, the second cell is candidate cell 538. Before the terminal device switches, the terminal device accesses the first cell, the first value is '10', and the second value is '00'. After the terminal device switches, the terminal device accesses the second cell, the third value is '10', and the fourth value is '00'. Among them, the first field of the first value and the first field of the third value correspond to the first cell, the first field of the second value and the first field of the fourth value correspond to the second cell, the first value is the same as the third value, and the second value is the same as the fourth value. It can be seen that based on the above-mentioned first rule, before and after the terminal device switches, the one-to-one correspondence between the value of the first field and the cell is fixed.

[0184] Exemplarily, when the correspondence between the value of the first field and the candidate cells is mapped according to the order of the candidate cells containing RACH resources in the LTM configuration, during the switching of the terminal device between cells, the value of the first field corresponds to the candidate cells and the current serving cell according to the configuration order or identification of the candidate cells, and, in the correspondence, except for the serving cell, the correspondence between the non-serving cells will not change with the switching of the terminal device. Unless, RRC reconfigures the candidate cell list of LTM.

[0185] For example, in the RRC configuration signaling, the LTM configuration includes the following correspondence:

[0186] LTM-candidate Cell ID = 0, corresponding to Physical cell ID = 538 (with RACH configuration)

[0187] LTM-candidate Cell ID = 1, corresponding to Physical cell ID = 1002

[0188] LTM-candidate Cell ID = 2, corresponding to Physical cell ID = 123 (current serving cell, with RACH configuration)

[0189] LTM-candidate Cell ID = 3, corresponding to Physical cell ID = 356

[0190] LTM-candidate Cell ID = 4, corresponding to Physical cell ID = 432

[0191] LTM-candidate Cell ID = 5, corresponding to Physical cell ID = 974

[0192] LTM-candidate Cell ID = 6, corresponding to Physical cell ID = 176 (with RACH configuration)

[0193] Based on the list order of candidate cells containing RACH resources in the above LTM configuration (the logical identifiers of candidate cells configured with random access resources are in ascending order), mapped to the first field with different values, we can get:

[0194] LTM-candidate Cell ID = 2, corresponding to Physical cell ID = 123, which is the current serving cell, corresponding to '00'

[0195] LTM-candidate Cell ID = 0, corresponding to Physical cell ID = 538, corresponding to '01'

[0196] LTM-candidate Cell ID = 2, corresponding to Physical cell ID = 123, which is the current serving cell and the second cell in the candidate cell list that is configured with random access resources, so it corresponds to '10'

[0197] LTM-candidate Cell ID = 6, corresponding to Physical cell ID = 176, corresponding to '11'

[0198] In this example, the serving cell is indicated by the minimum value of the first field, and the remaining values ​​of the first field correspond one by one to the candidate cells configured with random access resources. The corresponding order is from small to large according to the candidate cell configuration identifier, and corresponds to the remaining values ​​of the first field except the minimum value from small to large.

[0199] It should be understood that in the present application, the corresponding order can also be from large to small, or the corresponding order can be understood according to the physical cell identifier, or regardless of whether the candidate cell is configured with random access resources, it corresponds to the value of the first field.

[0200] The method of this example also includes that if the terminal device is triggered to send a random access request message 1 to the serving cell by the first field of the minimum value in the first information, the terminal device will attempt to receive a random access request response message (random access response, RAR) on the preconfigured time-frequency resources; if the terminal device is triggered to send a random access request message 1 to the serving cell by the first field of other values ​​other than the minimum value in the first information, the terminal device may no longer attempt or consider receiving a random access request response message for the random access request message 1. It should be understood that the other values ​​other than the minimum value in the above-mentioned first information correspond to the values ​​of the serving cell.

[0201] For example, in this example, the first field with the minimum value of '00' corresponds to the cell PCI123 (the current serving cell), and the first field with the value of '10' also corresponds to the cell PCI123. If the terminal device is triggered to send a random access request message 1 to the cell PCI123 by the first field with the value of '00', the terminal device may attempt to receive a random access request response message on the preconfigured time-frequency resources; if the terminal device is triggered to send a random access request message 1 to the cell PCI123 by the first field with the value of '10', the terminal device may no longer attempt or consider receiving a random access request response message for the random access request message 1.

[0202] For ease of understanding, Figure 3 As shown, the corresponding relationship between the value of the first field and the cell before and after the terminal device is switched is shown.

[0203] Before switching, the first field with a value of '00' corresponds to the original service cell (cell PCI123), the first field with a value of '01' corresponds to cell PCI538, the first field with a value of '10' corresponds to cell PCI123, and the first field with a value of '11' corresponds to cell PCI176.

[0204] After switching to cell PCI538, the first field with a value of '00' corresponds to the new service cell (cell PCI538), the first field with a value of '01' corresponds to cell PCI538, the first field with a value of '10' corresponds to cell PCI123, and the first field with a value of '11' corresponds to cell PCI176.

[0205] It can be seen that before and after the switching, except that the cell corresponding to '00' changes with the change of the serving cell of the terminal device, the cells corresponding to the values ​​of the first field with the values ​​of '01', 10' and '11' are fixed.

[0206] In this example, the serving cell of the terminal device may correspond to two first fields with different values. For example, the serving cell of the terminal device is cell PCI123, and the corresponding first field has values ​​of '00' and '10'.

[0207] Similarly, the terminal equipment switches continuously between cells based on Figure 3 , after the terminal device switches to the cell PCI538, it can also switch back to the cell PCI123. When the terminal device switches back to the cell PCI123, the first field with a value of '00' corresponds to the cell PCI123, the first field with a value of '01' corresponds to the cell PCI538, the first field with a value of '10' corresponds to the cell PCI123, and the first field with a value of '11' corresponds to the cell PCI176. Alternatively, after the terminal device switches to the cell PCI538, it can also switch to the cell PCI176. When the terminal device switches to the cell PCI176, the first field with a value of '00' corresponds to the cell PCI176, the first field with a value of '01' corresponds to the cell PCI538, the first field with a value of '10' corresponds to the cell PCI123, and the first field with a value of '11' corresponds to the cell PCI176.

[0208] Method 2: The first rule can be updated dynamically.

[0209] It should be noted that the first rule of dynamic update can be understood as the correspondence between the value of the first field and the cell can be dynamically updated. The cell can include a candidate cell and a serving cell currently accessed by the terminal device.

[0210] In an embodiment of the present application, a terminal device receives first information from a first network device of a first cell, the first information includes a first field, the first field is used to indicate a candidate cell; or the first field is used to indicate a candidate cell and a serving cell currently accessed by the terminal device; the terminal device determines the first cell or the second cell according to the first information and the first rule, wherein the first cell is the serving cell currently accessed by the terminal device, the second cell is a candidate cell, and the first rule is used to indicate the correspondence between the first field and the candidate cell; or the first rule is used to indicate the correspondence between the first field and the candidate cell and the correspondence between the first field and the serving cell currently accessed by the terminal device. Specifically, the first field of the first value corresponds to the first cell (the serving cell currently accessed by the terminal device), and the first field of the second value corresponds to the second cell (one of the candidate cells of the terminal device). The terminal device determines the second cell according to the first field of the second value in the first information and the first rule, and sends a random access request message 1 to the second cell. After the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, and the second cell is the serving cell after the terminal device switches. The first rule after switching is updated as follows: the first field of the first value corresponds to the second cell, and the first field of the fifth value corresponds to the first cell.

[0211] It can be seen that in mode 2, before the terminal device switches, the first field of the first value corresponds to the first cell; after the terminal device switches, the first field of the first value corresponds to the second cell. The first field of the first value corresponds to the service cell of the terminal device. Due to the switching of the terminal device, the service cell of the terminal device is also constantly changing, and the cell corresponding to the first field of the first value will also change continuously with the switching of the terminal device.

[0212] It should be noted that before the terminal device is switched to the second cell, it is connected to the first network device of the first cell. The first cell is a cell configured with a random access resource configuration, and it can be understood that the random access resource configuration of the first cell also belongs to the random access resource configuration of the candidate cell. For example, the random access resource configuration of the first cell also exists in the random access resource configuration of the LTM candidate cell.

[0213] In the first rule of the second method, when the first field of the first value corresponds to the service cell of the terminal device (including the service cell currently accessed by the terminal device, and the service cell after the terminal device switches, such as the first cell before switching and the second cell after switching), the first value is the minimum value. For example, the first value can be '0', '00' or '000'.

[0214] Alternatively, a first field with a fixed value corresponds to the serving cell of the terminal device. For example, the fixed value may be the minimum value of the first field ('0', '00' or '000').

[0215] Exemplarily, when the terminal device accesses the first cell, the first cell is the service cell currently accessed by the terminal device, and the first field of the first value corresponds to the first cell. When the terminal device accesses the second cell, the second cell is the service cell after the terminal device switches, and the first field of the first cell corresponds to the second cell.

[0216] It can be seen that in the second mode, the cell corresponding to the first field of the first value can dynamically change according to the different service cells of the terminal device. The value of the first field corresponds to the cell, and the corresponding relationship changes with the switching of the terminal device. Among them, the correspondence between the value of the first field and the cell can be understood as that the value of the first field corresponds to the physical identifier of the cell.

[0217] Based on the first rule of the second method, when the terminal device switches from the first cell to the second cell, the first field of the first value is updated from corresponding to the first cell to corresponding to the second cell. At the same time, the first cell is updated to correspond to the first field of the fifth value.

[0218] It should be understood that the fifth value may be the same as the second value or may be different from the second value.

[0219] Optionally, the fifth value is the same as the second value.

[0220] It should be noted that when the terminal device switches from the first cell to the second cell, the first cell corresponds to the value of the first field corresponding to the second cell before the switch. In other words, the corresponding relationship of the value of the first field is exchanged between the original service cell (first cell) and the new service cell (second cell).

[0221] For example, Figure 4 As shown, the corresponding relationship between the value of the first field and the cell before and after the terminal device is switched is shown.

[0222] Before switching, the first field value of '000' corresponds to the original service cell, the first field value of '001' corresponds to candidate cell 1, the first field value of '010' corresponds to candidate cell 2, the first field value of '011' corresponds to candidate cell 3, the first field value of '100' corresponds to candidate cell 4, the first field value of '101' corresponds to candidate cell 5, the first field value of '110' corresponds to candidate cell 6, and the first field value of '111' corresponds to candidate cell 7.

[0223] After switching to candidate cell 2, the first field with a value of '000' corresponds to the new service cell (candidate cell 2), the first field with a value of '001' corresponds to candidate cell 1, the first field with a value of '010' corresponds to the original service cell, the first field with a value of '011' corresponds to candidate cell 3, the first field with a value of '100' corresponds to candidate cell 4, the first field with a value of '101' corresponds to candidate cell 5, the first field with a value of '110' corresponds to candidate cell 6, and the first field with a value of '111' corresponds to candidate cell 7.

[0224] It can be seen that before and after the handover, the cells corresponding to the first field with a value of '000' and the cells corresponding to the first field with a value of '010' are swapped, where '000' is the first value and '010' is the second value.

[0225] Based on this, the updated first rule can be determined according to the corresponding relationship of the first field of the second value, that is, the updated first rule is related to the corresponding relationship of the first field of the second value. The first field of the second value is that the corresponding cell (the second cell) becomes the newly accessed service cell of the terminal device after switching, and the cell will correspond to the first field of the first value; the service cell (the first cell) originally accessed by the terminal device will become a candidate cell and correspond to the first field of the second value. In this case, the fifth value is the same as the second value. For example, both are '010'.

[0226] Optionally, the fifth value is different from the second value.

[0227] In the first case, when the terminal device switches from the first cell to the second cell, the value of the first field corresponding to the first cell may be defaulted to the maximum value. That is, after the terminal device switches, the first cell corresponds to the first field with the maximum value.

[0228] For example, Figure 5 As shown, the corresponding relationship between the value of the first field and the cell before and after the terminal device is switched is shown.

[0229] Before switching, the first field value of '000' corresponds to the original service cell, the first field value of '001' corresponds to candidate cell 1, the first field value of '010' corresponds to candidate cell 2, the first field value of '011' corresponds to candidate cell 3, the first field value of '100' corresponds to candidate cell 4, the first field value of '101' corresponds to candidate cell 5, the first field value of '110' corresponds to candidate cell 6, and the first field value of '111' corresponds to candidate cell 7.

[0230] After switching to candidate cell 2, the first field with a value of '000' corresponds to the new service cell (candidate cell 2), the first field with a value of '001' corresponds to candidate cell 1, the first field with a value of '010' corresponds to candidate cell 3, the first field with a value of '011' corresponds to candidate cell 4, the first field with a value of '100' corresponds to candidate cell 5, the first field with a value of '101' corresponds to candidate cell 6, the first field with a value of '110' corresponds to candidate cell 7, and the first field with a value of '111' corresponds to the original service cell.

[0231] It can be seen that when the terminal device switches from the original serving cell to the candidate cell 2, the candidate cell 2 corresponds to the first field with a value of '000', and the original serving cell corresponds to the first field with a value of '111'. Among them, the value '111' is the maximum value of the first field. It can also be understood that, Figure 5 A corresponding order between the first field value and the cell is shown. After the terminal device is switched, the original service cell can be arranged at the last position of the corresponding order by default.

[0232] Based on this, the updated first rule can be determined according to the first order. The first order can be understood as follows Figure 5 As shown in , before the switch, the first field corresponds to the cell logical identifier in ascending order. Since the original service cell corresponds to the last digit of the first order after the terminal device switches, the values ​​of the first fields corresponding to other candidate cells may also change accordingly. For example, before the switch, candidate cell 7 corresponds to the first field with a value of '111', and after the switch, candidate cell 7 corresponds to the first field with a value of '110'. It can be seen that in the first case, the fifth value is different from the second value. For example, the second value is '010' and the fifth value is '111'.

[0233] Exemplarily, the first order may be an initial default order, or an order predefined according to certain rules.

[0234] In the second case, after the terminal device switches from the first cell to the second cell, the first rule is determined according to the order of the candidate cells configured with random access resource configurations.

[0235] It should be noted that the new candidate cell containing RACH resources may be the original serving cell. The order of the candidate cells configured with random access resources can be determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

[0236] For example, according to the list of candidate cells containing RACH resources in the LTM configuration (the logical identifiers of the candidate cells configured with random access resources are in ascending order), mapped to the first field with different values, the following is obtained:

[0237] LTM-candidate Cell ID = 0, corresponding to Physical cell ID = 538, corresponding to '00'

[0238] LTM-candidate Cell ID = 1, corresponding to Physical cell ID = 1002, corresponding to '01'

[0239] LTM-candidate Cell ID = 2, corresponding to Physical cell ID = 123, corresponding to '10'

[0240] LTM-candidate Cell ID = 6, corresponding to Physical cell ID = 736, corresponding to '11'

[0241] The original serving cell 538 of the terminal device corresponds to the first field with a value of '00', and the terminal device can switch from the original serving cell 538 to the new serving cell 123. The new serving cell 123 corresponds to the first field with a value of '10' before switching.

[0242] After the terminal device switches from the original serving cell 538 to the new serving cell 123, the correspondence between the value of the first field and the cell can be updated as follows:

[0243] LTM-candidate Cell ID = 2, corresponding to Physical cell ID = 123, corresponding to '00'

[0244] LTM-candidate Cell ID = 0, corresponding to Physical cell ID = 538, corresponding to '01'

[0245] LTM-candidate Cell ID = 1, corresponding to Physical cell ID = 1002, corresponding to '10'

[0246] LTM-candidate Cell ID = 6, corresponding to Physical cell ID = 736, corresponding to '11'

[0247] It can be seen that the new serving cell will correspond to the first field with the minimum value of '00', and the original serving cell 538 can exist in the LTM configuration as a new candidate cell with RACH resources. In addition to the new serving cell 123, the order of other candidate cells with RACH resource configuration in the LTM configuration is: candidate cell 538 corresponding to LTM-candidate Cell ID=0, candidate cell 1002 corresponding to LTM-candidate Cell ID=1, and candidate cell 736 corresponding to LTM-candidate Cell ID=6. In the second case, the first rule is updated according to the order of candidate cells configured with random access resource configuration. Based on this, the order of random access resource configuration of the candidate cells is candidate cell 538, candidate cell 1002, and candidate cell 736, and the corresponding values ​​of the first field are '01', '10', and '11' from small to large.

[0248] Therefore, in the second case, the fifth value is different from the second value. For example, the second value is '10' and the fifth value is '01'.

[0249] In the third case, after the terminal device switches from the first cell to the second cell, the first rule is determined according to the order of the identifiers of the candidate cells, where the identifiers of the candidate cells can be understood as physical identifiers of the candidate cells.

[0250] For example, the correspondence between the first field with different values ​​before the terminal device switches and the cell is as follows:

[0251] Physical cell ID = 123, corresponding to '00'

[0252] Physical cell ID = 538, corresponding to '01'

[0253] Physical cell ID = 736, corresponding to '10'

[0254] Physical cell ID = 1002, corresponding to '11'

[0255] The original serving cell 123 of the terminal device corresponds to the first field with a value of '00', and the terminal device can switch from the original serving cell 123 to the new serving cell 1002. The new serving cell 1002 corresponds to the first field with a value of '11' before switching.

[0256] After the terminal device switches from the original serving cell 123 to the new serving cell 1002, the correspondence between the value of the first field and the cell can be updated as follows:

[0257] Physical cell ID = 1002, corresponding to '00'

[0258] Physical cell ID = 123, corresponding to '01'

[0259] Physical cell ID = 538, corresponding to '10'

[0260] Physical cell ID = 736, corresponding to '11'

[0261] It can be seen that the new service cell 1002 will correspond to the first field with the minimum value of '00', and the original service cell 123 will correspond to the first field with the value of '01' in the order of the candidate cell physical identifiers (for example, the candidate cell physical identifiers are in the order from small to large: cell 123, cell 538, cell 736).

[0262] Therefore, in the third case, the fifth value is different from the second value. For example, the second value is '11' and the fifth value is '01'.

[0263] In summary, when the terminal device switches between different cells, the first rule can be dynamically updated according to the order of the candidate cells configured with random access resource configuration, the first order, the correspondence between the first field of the second value, the order of the identifiers of the candidate cells, etc. The configuration of the random access resources of the original service cell accessed by the terminal device also belongs to the configuration of the random access resources of the candidate cell, so that the terminal device can flexibly switch back and forth between different candidate cells.

[0264] In addition, in another implementation, the first information may further include a second field. The second field is used to indicate whether the terminal device triggers sending a random access request message 1 (preamble) to the first cell. The second field may be a 1-bit newly added to the first information. Whether the terminal device triggers access to the currently serving cell may be controlled by 1 bit.

[0265] In an embodiment of the present application, a terminal device receives first information from a first network device in a first cell, the first information includes a first field, the first field is used to indicate a candidate cell, the first information also includes a second field, the second field is used to indicate whether the terminal device triggers sending a random access request message 1 to the first cell; the terminal device determines the first cell or the second cell based on the first information and the first rule, wherein the first cell is a service cell currently accessed by the terminal device, the second cell is a candidate cell, and the first rule is used to indicate the correspondence between the first field and the candidate cell.

[0266] For example, Figure 6As shown, a schematic diagram of the field structure of the first information is shown. It includes a synchronization signal block index (synchronization signal block index, SSB index), a mask index (physical random access channel mask index, PRACH Mask index), a preamble index (random access preamble index), a cell identifier (cell indicator), a random access request retransmission identifier (PRACH retransmission indicator) and a serving cell random access identifier (serving cell RACH flag). The first field is Figure 6 The cell indicator shown in the second field is Figure 6 The serving cell RACH flag shown in the figure, the retransmission flag of the random access request is used to instruct the terminal device to trigger the sending of the random access request message 1 this time, including the initial transmission or the retransmission.

[0267] Optionally, in the RRC configuration DCI format, the second field can be selected to be turned on or off.

[0268] When the second field value is the sixth value, the first field is a padding field, and the terminal device can determine to send a random access request message 1 to the first cell according to the second field in the first information.

[0269] Exemplarily, when the sixth value is 1, the second field is used to indicate that the terminal device can trigger random access to the currently accessed serving cell (first cell). At this time, the value of the first field can be regarded as meaningless, and the terminal device can ignore the first field, or regard the first field as a filler bit. The PDCCH used to transmit the first information is only used to indicate the RACH of the currently accessed serving cell (first cell), that is, Figure 6 The SSB index shown is the SSB index of the currently accessed service cell, and the PRACH resource is the PRACH resource of the currently accessed service cell.

[0270] When the second field value is the seventh value, before the terminal device determines the second cell according to the first information and the first rule, the terminal device can determine not to send a random access request message 1 to the first cell according to the second field in the first information.

[0271] Exemplarily, when the seventh value is 0, the second field is used to indicate that the terminal device cannot trigger random access to the currently accessed serving cell (first cell). At this time, the currently accessed serving cell does not belong to the candidate cell, and the PDCCH used to transmit the first information is only used to indicate the RACH of the candidate cell, and the value of the first field corresponds to the candidate cell containing the RACH.

[0272] The corresponding relationship between the value of the first field and the candidate cells containing RACH can be determined according to the order of random access resource configuration of the candidate cells. For example, the corresponding relationship introduced in the first method above will not be repeated here.

[0273] Alternatively, the value of the first field is mapped to the physical identifier of the candidate cell in order from large to small, for example, the corresponding relationship described in the third case above, which will not be repeated here. If the mapping relationship includes the currently connected service cell, the value of the first field of the currently connected service cell (for example, the first cell) is invalid. When the terminal device switches from the first cell to other candidate cells, the first cell can be understood as a candidate cell, and the value of the first field corresponding to the first cell is valid.

[0274] Based on the above scheme, the terminal device can be displayed and instructed to switch to a candidate cell, or trigger access to the current service cell through the second field in the first information, so that the terminal device can flexibly switch back and forth between different cells.

[0275] It should be understood that in the embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0276] It is understandable that in the above-mentioned various method embodiments, the method implemented by the terminal device can also be implemented by a component (such as a chip or circuit) that can be used in the terminal, and the method implemented by the network device can also be implemented by a component (such as a chip or circuit) that can be used in the network device. Figures 2 to 6 The method of the embodiment of the present application is described in detail. Figures 7 to 10 A communication device according to an embodiment of the present application is described.

[0277] Figure 7 A schematic diagram of the structure of a communication device provided in an embodiment of the present application, the communication device may include: a processing unit 710 and a transceiver unit 720.

[0278] The communication device 700 provided in this application may correspond to the above Figures 2 to 6The process executed by the terminal device in the method embodiment and the functions of each unit / module in the communication device can be found in the description above, and the detailed description is appropriately omitted here.

[0279] It should be understood that Figure 7 The communication device shown may be a terminal device, and may also be applicable to a chip or an integrated circuit in the terminal device.

[0280] Taking the communication device as a terminal device as an example, Figure 8 A schematic diagram of the structure of a terminal device provided in an embodiment of the present application is provided for ease of understanding and illustration. Figure 8 In the example, the terminal device takes a mobile phone as an example. Figure 8 Only the main components of the terminal device are shown. Figure 8 The terminal device 800 shown includes a processor, a memory, a control circuit and an antenna. Optionally, the terminal device may also include an input and output device. It should be understood that the control circuit may be arranged in the processor or may be located outside the processor and exist independently, and the embodiments of the present application are not limited thereto. The processor is mainly used to process the communication protocol and the communication data, and to control the entire terminal device, execute the software program, and process the data of the software program, for example, to support the terminal device to perform the actions described in the above method embodiment. The memory is mainly used to store software programs and data. The control circuit is mainly used for the conversion between the baseband signal and the radio frequency signal and the processing of the radio frequency signal. The control circuit and the antenna together may also be called a transceiver, which is mainly used for transmitting and receiving radio frequency signals in the form of electromagnetic waves. Input and output devices, such as a touch screen, a display screen, a keyboard, etc., are mainly used to receive data input by the user and output data to the user.

[0281] When the terminal device is turned on, the processor can read the software program in the storage unit, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor performs baseband processing on the data to be sent, and outputs the baseband signal to the RF circuit. The RF circuit performs RF processing on the baseband signal and then sends the RF signal outward in the form of electromagnetic waves through the antenna. When data is sent to the terminal device, the RF circuit receives the RF signal through the antenna, converts the RF signal into a baseband signal, and outputs the baseband signal to the processor. The processor converts the baseband signal into data and processes the data.

[0282] Those skilled in the art will appreciate that for ease of description, Figure 8 Only one memory and processor are shown. In an actual terminal device, there may be multiple processors and memories. The memory may also be referred to as a storage medium or a storage device, etc., which is not limited in the embodiments of the present application. It should be understood that the memory may be integrated in the processor or may be located outside the processor and exist independently, which is not limited in the embodiments of the present application.

[0283] As an optional implementation, the processor may include a baseband processor and a central processing unit. The baseband processor is mainly used to process the communication protocol and communication data, and the central processing unit is mainly used to control the entire terminal device, execute software programs, and process software program data. Figure 8 The processor in the can integrate the functions of the baseband processor and the central processing unit. Those skilled in the art can understand that the baseband processor and the central processing unit can also be independent processors, which are interconnected through technologies such as buses. Those skilled in the art can understand that the terminal device can include multiple baseband processors to adapt to different network standards, and the terminal device can include multiple central processing units to enhance its processing capabilities. The various components of the terminal device can be connected through various buses. The baseband processor can also be expressed as a baseband processing circuit or a baseband processing chip. The central processing unit can also be expressed as a central processing circuit or a central processing chip. The function of processing the communication protocol and communication data can be built into the processor, or it can be stored in the storage unit in the form of a software program, and the processor executes the software program to realize the baseband processing function.

[0284] In the embodiment of the present application, the antenna and the control circuit having the transceiver function can be regarded as the transceiver unit 801 of the terminal device 800, for example, for supporting the terminal device to perform the following Figures 2 to 6 The transceiver function performed by the terminal device in the implementation of the method. The processor with processing function is regarded as the processing unit 802 of the terminal device 800, which is Figure 7 The processing unit 710 in FIG. Figure 8 As shown, the terminal device 800 includes a transceiver unit 801 and a processing unit 802. The transceiver unit may also be called a transceiver, a transceiver, a transceiver device, etc. Figure 7 801 corresponds to the transceiver unit 720 in . Optionally, the device used to implement the receiving function in the transceiver unit 801 can be regarded as a receiving unit, and the device used to implement the sending function in the transceiver unit 801 can be regarded as a sending unit, that is, the transceiver unit 801 includes a receiving unit and a sending unit, the receiving unit can also be called a receiver, an input port, a receiving circuit, etc., and the sending unit can be called a transmitter, a transmitter or a transmitting circuit, etc. It can be understood that the transceiver unit can also be an interface circuit.

[0285] The processing unit 802 can be used to execute the instructions stored in the memory to control the transceiver unit 801 to receive signals and / or send signals to complete the functions of the terminal device in the above method embodiment. As an implementation method, the functions of the transceiver unit 801 can be considered to be implemented by a transceiver circuit or a dedicated chip for transceiver.

[0286] It should be understood that Figure 8The terminal device 800 shown can implement Figures 2 to 6 The method embodiment involves various processes of the terminal device. The operations and / or functions of each module in the terminal device 800 are respectively to implement the corresponding processes in the above method embodiment. For details, please refer to the description in the above method embodiment. To avoid repetition, the detailed description is appropriately omitted here.

[0287] Fig. 9 It is a structural diagram of a communication device provided in an embodiment of the present application. The device 900 may include a processing unit 910 and a transceiver unit 920.

[0288] The communication device 900 provided in this application may correspond to the above Figures 2 to 6 The process executed by the first network device in the method embodiment and the functions of each unit / module in the communication device can be found in the above description, and the detailed description is appropriately omitted here.

[0289] It should be understood that Fig. 9 The communication device described may be a network side device, or may be a chip or integrated circuit that can be used in the network device side.

[0290] It should be understood that the network side device can represent any network device that communicates with the terminal device, or it can represent the whole composed of multiple network devices that communicate with the terminal device. The embodiments of the present application are not limited to this.

[0291] The network device 1000 may include one or more radio frequency units, such as a remote radio unit (RRU) 1010 and one or more baseband units (BBU) 1020 (also referred to as digital units, DU). The RRU may be referred to as a transceiver unit 1010. Fig. 9 The transceiver unit 920 in the embodiment corresponds to the transceiver unit 920 in the embodiment. Optionally, the transceiver unit can also be called a transceiver, a transceiver circuit, or a transceiver, etc., which can include at least one antenna 1011 and a radio frequency unit 1012. The RRU part is mainly used for receiving and transmitting radio frequency signals and converting radio frequency signals into baseband signals. The BBU part is mainly used for baseband processing, controlling the base station, etc. The RRU and BBU can be physically arranged together or physically separated, that is, a distributed base station. It can be understood that the transceiver unit can also be an interface circuit.

[0292] The BBU 1020 is the control center of the base station, which can also be called a processing unit 1020. Fig. 9 Corresponding to the processing unit 910 in the , it is mainly used to complete the baseband processing function.

[0293] In one example, the BBU 1020 may be composed of one or more single boards, and multiple single boards may jointly support a wireless access network of a single access standard (such as an LTE network), or may respectively support wireless access networks of different access standards (such as an LTE network, a 5G network, or other networks). The BBU 1020 also includes a memory 1021 and a processor 1022. The memory 1021 is used to store necessary instructions and data. The processor 1022 is used to control the base station to perform necessary actions. It should be understood that the memory may be integrated in the processor, or may be located outside the processor and exist independently, and the embodiments of the present application are not limited to this. The memory 1021 and the processor 1022 may serve one or more single boards. In other words, a memory and a processor may be separately set on each single board. It is also possible that multiple single boards share the same memory and processor. In addition, necessary circuits may be set on each single board.

[0294] It should be understood that Fig.10 The network device 1000 shown can implement Figures 2 to 6 The method embodiment involves various processes of the network device. The operations and / or functions of each module in the network device 1000 are respectively to implement the corresponding processes in the above method embodiment. For details, please refer to the description in the above method embodiment. To avoid repetition, the detailed description is appropriately omitted here.

[0295] An embodiment of the present application also provides a processing device, including a processor and an interface; the processor is used to execute the communication method in any of the above method embodiments.

[0296] It should be understood that the above-mentioned processing device can be a chip. For example, the processing device can be a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), a system on chip (SoC), a central processor unit (CPU), a network processor (NP), a digital signal processor (DSP), a microcontroller unit (MCU), a programmable logic device (PLD) or other integrated chips.

[0297] In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software modules in a processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

[0298] It can be understood that the memory in the embodiment of the present invention can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0299] An embodiment of the present application also provides a communication system, which includes the aforementioned network device and terminal device.

[0300] The embodiment of the present application further provides a computer-readable medium on which a computer program is stored. When the computer program is executed by a computer, the method in any of the above method embodiments is implemented.

[0301] The embodiment of the present application also provides a computer program product, which implements the method in any of the above method embodiments when executed by a computer.

[0302] 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, a solid state disk (SSD)).

[0303] The network devices in the above-mentioned various device embodiments completely correspond to the network devices or terminal devices in the terminal devices and method embodiments, and the corresponding modules or units perform the corresponding steps. For example, the sending module (transmitter) method performs the sending steps in the method embodiment, and the receiving module (receiver) performs the receiving steps in the method embodiment. The other steps except sending and receiving can be performed by the processing module (processor). The functions of the specific modules can refer to the corresponding method embodiments. The sending module and the receiving module can form a transceiver module, and the transmitter and the receiver can form a transceiver to jointly realize the transceiver function; the processor can be one or more.

[0304] In the present application, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0305] The terms "component", "module", "system", etc. used in this specification are used to represent computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program and / or a computer. By way of illustration, both applications running on a computing device and a computing device can be components. One or more components may reside in a process and / or an execution thread, and a component may be located on a computer and / or distributed between two or more computers. In addition, these components may be executed from various computer-readable media having various data structures stored thereon. Components may, for example, communicate through local and / or remote processes according to signals having one or more data packets (e.g., data from two components interacting with another component between a local system, a distributed system and / or a network, such as the Internet interacting with other systems through signals).

[0306] Those of ordinary skill in the art will appreciate that the various illustrative logical blocks and steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or in a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0307] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0308] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0309] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0310] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0311] 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. A communication method, characterized in that: include: Receiving first information from a first network device, where a first cell belongs to the first network device, where the first cell is a serving cell currently accessed by a terminal device, and where the first information includes a first field, where the first field is used to indicate a candidate cell, or where the first field is used to indicate the candidate cell and the serving cell currently accessed by the terminal device; determining the first cell or the second cell according to the first information and a first rule, the second cell belongs to the candidate cell, the second cell belongs to the first network device, or the second cell belongs to a second network device, wherein the first rule is used to indicate a correspondence between the first field and the candidate cell; Or the first rule is used to indicate the correspondence between the first field and the candidate cell and the correspondence between the first field and the serving cell currently accessed by the terminal device.

2. The method according to claim 1, characterized in that The method further comprises: According to the first information and the first rule, a random access request message 1 is sent to the first cell or the second cell.

3. The method according to claim 1 or 2, characterized in that: The first cell is a cell configured with random access resource configuration, and the first rule includes: The first field having a first value corresponds to the first cell, and the first fields having other values ​​correspond to different candidate cells; The first information includes a first field of the second value.

4. The method according to claim 3, characterized in that The initiating random access to the first cell or the second cell according to the first information and the first rule includes: According to the first field of the first value and the first rule, a random access request message 1 is sent to the first cell.

5. The method according to claim 3, characterized in that: The initiating random access to the first cell or the second cell according to the first information and the first rule includes: According to the first field with other values ​​and the first rule, a random access request message 1 is sent to different candidate cells.

6. The method according to any one of claims 1 to 5, characterized in that After the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the serving cell after the terminal device switches, and the first rule is: The first field of the third value corresponds to the first cell, and the first field of the fourth value corresponds to the second cell; The first rule is determined according to the order of candidate cells configured with random access resource configurations.

7. The method according to claim 6, characterized in that The first field of the second value corresponds to the second cell, wherein the fourth value is a minimum value.

8. The method according to any one of claims 1 to 6, characterized in that After the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the serving cell after the terminal device switches, and the first rule is updated as follows: The first field of the first value corresponds to the second cell, and the first field of the fifth value corresponds to the first cell.

9. The method according to claim 8, characterized in that The first updated rule is related to one of the following: The order of candidate cells configured with random access resource configuration, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

10. The method according to claim 9, characterized in that The order of the candidate cells configured with random access resource configuration is determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

11. The method according to any one of claims 8 to 10, characterized in that When the first field of the first value corresponds to a service cell currently accessed by the terminal device, or corresponds to a service cell after the terminal device is switched, the first value is a minimum value.

12. The method according to claim 1, characterized in that The first information includes a second field, and the second field is used to indicate whether the terminal device triggers sending a random access request message 1 to the first cell.

13. The method according to claim 12, characterized in that When the second field takes the sixth value, the first field is a padding field. The determining the second cell according to the first information and the first rule includes: Determine, according to the second field in the first information, that the random access request message 1 is sent to the first cell.

14. The method according to claim 12, characterized in that When the value of the second field is the seventh value, before determining the second cell according to the first information and the first rule, the method further includes: Determine not to send the random access request message 1 to the first cell according to the second field in the first information.

15. A communication method, characterized in that: include: The first network device sends first information to the terminal device, where the first information is used to instruct the terminal device to determine the first cell or the second cell according to the first rule; The first cell belongs to the first network device, the first cell is a serving cell currently accessed by the terminal device, and the first information includes a first field, and the first field is used to indicate a candidate cell; Or the first field is used to indicate the candidate cell and the service cell currently accessed by the terminal device, the second cell belongs to the candidate cell, the second cell belongs to the first network device, or the second cell belongs to the second network device, and the first rule is used to indicate the correspondence between the first field and the candidate cell, or the first rule is used to indicate the correspondence between the first field and the candidate cell and the correspondence between the first field and the service cell currently accessed by the terminal device.

16. The method according to claim 15, characterized in that The first cell is a cell configured with random access resource configuration, and the first rule includes: The first field having a first value corresponds to the first cell, and the first fields having other values ​​correspond to different candidate cells; The first information includes a first field of the second value.

17. The method according to claim 15 or 16, characterized in that After the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the serving cell after the terminal device switches, and the first rule is: The first field of the third value corresponds to the first cell, and the first field of the fourth value corresponds to the second cell; The first rule is determined according to the order of candidate cells configured with random access resource configurations.

18. The method according to claim 17, characterized in that The first field of the second value corresponds to the second cell, wherein the fourth value is a minimum value.

19. The method according to claim 15 or 16, characterized in that After the terminal device switches from the first cell to the second cell, the first cell belongs to the candidate cell, the second cell is the serving cell after the terminal device switches, and the first rule is updated as follows: The first field of the first value corresponds to the second cell, and the first field of the fifth value corresponds to the first cell.

20. The method according to claim 19, characterized in that The first updated rule is related to one of the following: The order of candidate cells configured with random access resource configuration, the first order, the correspondence between the first field of the second value, and the order of the identifiers of the candidate cells.

21. The method according to claim 20, characterized in that The order of the candidate cells configured with random access resource configuration is determined from small to large according to the logical identifiers of the candidate cells configured with random access resources.

22. The method according to any one of claims 19 to 21, characterized in that When the first field of the first value corresponds to the service cell currently accessed by the terminal device, or corresponds to the service cell after the terminal device is switched, the first value is the minimum value.

23. The method according to claim 15, characterized in that The first information includes a second field, and the second field is used to indicate whether the terminal device triggers sending a random access request message 1 to the first cell.

24. The method according to claim 23, characterized in that When the value of the second field is the sixth value, the first field is a padding field.

25. A communication device, characterized in that: include: A processor coupled to a memory, the memory being used to store a computer program, the processor being used to run the computer program so that the communication device performs the method according to any one of claims 1 to 14.

26. A communication device, characterized in that: include: A processor coupled to a memory, the memory being used to store a computer program, the processor being used to run the computer program so that the communication device performs the method according to any one of claims 15 to 24.

27. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a computer, the computer is caused to implement the method according to any one of claims 1 to 14, or 15 to 24.

28. A computer program product comprising instructions, characterized in that When the computer program product is run on a computer, the computer is caused to perform the method according to any one of claims 1 to 14 or 15 to 24.

29. A chip, characterized in that: The chip includes a processor and a data interface, and the processor reads instructions stored in a memory through the data interface to execute the method as described in any one of claims 1 to 14, or 15 to 24.

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