Control information dci transmission method and related device
A DCI transmission method is provided, which includes: transmitting configuration information that is used for allocating N search space sets; dropping part or all of PDCCH candidates of at least one search space in a first search space set in a case that the number of PDCCH candidates in the first search space set is greater than a maximum number of PDCCH candidates supported by a terminal, to obtain a second search space set; and transmitting DCI on the second search space set; where the first search space set includes a first search space, the first search space is a search space for scheduling a second cell by a first cell, the first cell is a secondary cell, and the number of PDCCH candidates in the second search space set is less than or equal to the maximum number of PDCCH candidates supported by the terminal.
1 . A downlink control information (DCI) transmission method, comprising:
transmitting configuration information, wherein the configuration information is used for allocating N search space sets, and N is a positive integer;
dropping part or all of physical downlink control channel (PDCCH) candidates of at least one search space in a first search space set in a case that the number of PDCCH candidates in the first search space set is greater than a maximum number of PDCCH candidates supported by a terminal, so as to obtain a second search space set; and
transmitting DCI on the second search space set;
wherein the first search space set is any one of the N search space sets, at least one search space set in the N search space sets comprises a first search space, the first search space is a search space for scheduling a second cell by a first cell, the first cell is a secondary cell (SCell), and the number of PDCCH candidates in the second search space set is less than or equal to the maximum number of PDCCH candidates supported by the terminal;
wherein the maximum number of PDCCH candidates supported by the terminal comprises at least one of the following:
a maximum number X of PDCCH candidates corresponding to self-scheduling of a primary cell (PCell);
a maximum number Y of cross-carrier PDCCH candidates corresponding to scheduling of the PCell by the first cell; or
a maximum number P of PDCCH candidates supported by the PCell;
wherein the number of PDCCH candidates of the second search space set being less than or equal to the maximum number of PDCCH candidates supported by the terminal comprises at least one of the following:
the number of PDCCH candidates of a second search space in each second time unit is less than or equal to X, and the second search space is a search space for self-scheduling of the PCell; or
in a case that the number of PDCCH candidates of a third search space belongs to the number of PDCCH candidates of the PCell, the number of PDCCH candidates of the third search space in each second time unit is less than or equal to a first value;
wherein the second time unit is a time unit for an SCS of the PCell, and the third search space is a search space for scheduling the PCell by the SCell.
2 . The method according to claim 1 , wherein the configuration information is further used for allocating a corresponding quantity of PDCCH candidates for each of the search space sets.
3 . The method according to claim 2 , wherein Y comprises any one of the following:
a maximum number of PDCCH candidates using a first time unit in the first cell; and
a maximum number of PDCCH candidates using a second time unit in the first cell;
wherein the first time unit is a time unit for a subcarrier spacing (SCS) of the first cell, and the second time unit is a time unit for an SCS of the Pcell, or,
wherein P satisfies:
in a case that the number of PDCCH candidates of the third search space belongs to the number of PDCCH candidates of the PCell and Y is the maximum number of PDCCH candidates using the second time unit in the first cell, P=X+Y;
wherein the third search space is a search space for scheduling the PCell by the SCell.
4 . The method according to claim 2 , wherein the first value satisfies:
in a case that Y is the maximum number of PDCCH candidates using the first time unit in the PCell, the first value is Y.
5 . The method according to claim 2 , wherein in a case that the PCell supports overbooking of the number of PDCCH candidates, the second search space set corresponding to the PCell satisfies:
in a case that Y is the maximum number of PDCCH candidates using a second time unit in the PCell, a sum of the number of PDCCH candidates in the third search space and the number of PDCCH candidates in the second search space is less than or equal to X+Y;
wherein the second time unit is a time unit for an SCS of the PCell, the second search space is a search space for self-scheduling of the PCell, and the third search space is a search space for scheduling the PCell by the SCell.
6 . The method according to claim 2 , wherein in a case that the first cell supports overbooking of the number of PDCCH candidates, the second search space set corresponding to the first cell satisfies:
the number of PDCCH candidates in a second search space is less than or equal to P;
wherein the second search space is a search space for self-scheduling of the PCell, the third search space is a search space for scheduling the PCell by the SCell, and
wherein the second time unit is a time unit for an SCS of the PCell.
7 . The method according to claim 1 , wherein the dropping part or all of physical downlink control channel PDCCH candidates of at least one search space in a first search space set in a case that the number of PDCCH candidates in the first search space set is greater than a maximum number of PDCCH candidates supported by a terminal comprises:
dropping part or all of the PDCCH candidates of the at least one search space in the first search space set in a case that a total number of target PDCCH candidates is greater than a maximum total number of PDCCH candidates of a target cell that are supported by the terminal; wherein
the total number of target PDCCH candidates is a sum of the number of PDCCH candidates of all search spaces in M search spaces in a target time unit, the M search spaces are search spaces in the first search space set corresponding to the target cell, and the target time unit is a time unit for overbooking in the target cell,
wherein a time length of the target time unit is determined based on an SCS of the target cell.
8 . The method according to claim 7 , wherein in a case that the target cell is the PCell, priorities of search spaces in the first search space set corresponding to the PCell satisfies any one of the following:
a priority of a user-specific search space (USS) for self-scheduling of the PCell is higher than a priority of a third search space, and is lower than a priority of a common search space (CSS) for self-scheduling of the PCell; and
a priority of the third search space is higher than a priority of the USS for self-scheduling of the PCell, and is lower than the priority of the CSS for self-scheduling of the PCell; wherein
the third search space is a search space for scheduling the PCell by the SCell.
9 . The method according to claim 7 , wherein in a case that the target cell is the PCell, priorities of search spaces in the first search space set corresponding to the PCell satisfies: a priority of a CSS for self-scheduling of the PCell is greater than that of a USS in the first cell.
10 . The method according to claim 7 , wherein a dropping rule for dropping part or all of the PDCCH candidates of the at least one search space comprises:
dropping part or all of the PDCCH candidates in the search space in descending order or ascending order of indexes of the search spaces.
11 . The method according to claim 10 , wherein the dropping rule further comprises:
dropping the PDCCH candidates in ascending order of priorities by using PDCCH candidates in the search spaces as units.
12 . A communications device, comprising:
a processor; and
a memory storing a program that is capable of running on the processor, wherein the program, when executed by the processor, causes the communication device to:
transmit configuration information, wherein the configuration information is used for allocating N search space sets, and N is a positive integer;
drop part or all of physical downlink control channel (PDCCH) candidates of at least one search space in a first search space set in a case that the number of PDCCH candidates in the first search space set is greater than a maximum number of PDCCH candidates supported by a terminal, so as to obtain a second search space set; and
transmit downlink control information (DCI) on the second search space set;
wherein the first search space set is any one of the N search space sets, at least one search space set in the N search space sets comprises a first search space, the first search space is a search space for scheduling a second cell by a first cell, the first cell is a secondary cell (SCell), and the number of PDCCH candidates in the second search space set is less than or equal to the maximum number of PDCCH candidates supported by the terminal;
wherein the maximum number of PDCCH candidates supported by the terminal comprises at least one of the following:
a maximum number X of PDCCH candidates corresponding to self-scheduling of a primary cell (PCell);
a maximum number Y of cross-carrier PDCCH candidates corresponding to scheduling of the PCell by the first cell; or
a maximum number P of PDCCH candidates supported by the PCell;
wherein the number of PDCCH candidates of the second search space set being less than or equal to the maximum number of PDCCH candidates supported by the terminal comprises at least one of the following:
the number of PDCCH candidates of a second search space in each second time unit is less than or equal to X, and the second search space is a search space for self-scheduling of the PCell; or
in a case that the number of PDCCH candidates of a third search space belongs to the number of PDCCH candidates of the PCell, the number of PDCCH candidates of the third search space in each second time unit is less than or equal to a first value;
wherein the second time unit is a time unit for an SCS of the PCell, and the third search space is a search space for scheduling the PCell by the SCell.
13 . The communications device according to claim 12 , wherein the configuration information is further used for allocating a corresponding quantity of PDCCH candidates for each of the search space sets.
14 . The communications device according to claim 13 , wherein Y comprises any one of the following:
a maximum number of PDCCH candidates using a first time unit in the first cell; and
a maximum number of PDCCH candidates using a second time unit in the first cell;
wherein the first time unit is a time unit for a subcarrier spacing (SCS) of the first cell, and the second time unit is a time unit for an SCS of the Pcell; or,
wherein P satisfies:
in a case that the number of PDCCH candidates of the third search space belongs to the number of PDCCH candidates of the PCell and Y is the maximum number of PDCCH candidates using the second time unit in the first cell, P=X+Y;
wherein the third search space is a search space for scheduling the PCell by the SCell.
15 . The communications device according to claim 14 , wherein the first value satisfies:
in a case that Y is the maximum number of PDCCH candidates using the first time unit in the PCell, the first value is Y.
16 . The communications device according to claim 13 , wherein in a case that the PCell supports overbooking of the number of PDCCH candidates, the second search space set corresponding to the PCell satisfies:
in a case that Y is the maximum number of PDCCH candidates using a second time unit in the PCell, a sum of the number of PDCCH candidates in the third search space and the number of PDCCH candidates in the second search space is less than or equal to X+Y;
wherein the second time unit is a time unit for an SCS of the PCell, the second search space is a search space for self-scheduling of the PCell, and the third search space is a search space for scheduling the PCell by the SCell.
17 . The communications device according to claim 13 , wherein in a case that the first cell supports overbooking of the number of PDCCH candidates, the second search space set corresponding to the first cell satisfies:
the number of PDCCH candidates in a second search space is less than or equal to P;
wherein the second search space is a search space for self-scheduling of the PCell, the third search space is a search space for scheduling the PCell by the SCell, and the second time unit is a time unit for an SCS of the PCell.