Monitoring of downlink control channels for communication with multiple transmission-reception points
Methods and apparatuses for PDCCH candidate indication and determination. A method of operating a UE includes transmitting a first capability value and receiving a configuration of N cells DL,μ downlink cells scheduled by PDCCHs with SCS configuration μ and a configuration of a first group index for first CORESETs and of a second group index for second CORESETs per cell for N cells,1 DL,μ cells from the N cells DL,μ . The method further includes determining a total number M PDCCH total,slot,μ of PDCCH candidates per slot based on the first capability value, a number of the N cells,1 DL,μ cells, and a number of N cells,0 DL,μ cells for each SCS configuration μ, where N cells,0 DL,μ =N cells DL,μ −N cells,1 DL,μ . The method also includes receiving, per cell from the N cells DL,μ cells and per slot, a number of PDCCH candidates that is not larger than the minimum of: the total number M PDCCH total,slot,μ of PDCCH candidates per slot and a maximum predefined number M PDCCH max,slot,μ of PDCCH candidates per slot.
1. A user equipment (UE) comprising:
a transmitter configured to transmit a first capability value;
a receiver configured to receive:
a configuration of N cells DL,μ downlink cells scheduled by physical downlink control channels (PDCCHs) with a sub-carrier spacing (SCS) configuration μ; and
a configuration of a first group index for first control resource sets (CORESETs) and of a second group index for second CORESETs per cell for N cells,1 DL,μ from the N cells DL,μ ; and
a processor, operably connected to the receiver, configured to determine a total number M PDCCH total,slot,μ of PDCCH candidates per slot based on the first capability value, a number of the N cells,1 DL,μ cells, and a number of N cells,0 DL,μ for each SCS configuration μ, where N cells,0 DL,μ =N cells DL,μ −N cells,1 DL,μ ;
wherein the receiver is further configured to receive, per cell from the N cells DL,μ cells and per slot, a number of PDCCH candidates that is not larger than a minimum of:
the total number M PDCCH total,slot,μ of PDCCH candidates per slot, and
a maximum predefined number M PDCCH max,slot,μ of PDCCH candidates per slot.
2. The UE of claim 1 , wherein:
the transmitter is further configured to transmit a second capability value N cells cap , and
M PDCCH total,slot,μ =└N cells cap ·M PDCCH max,slot,μ ·N cells DL,μ /Σ j=0 3 N cells DL,j ┘, where Σ j=0 3 N cells DL,j >4.
3. The UE of claim 1 , wherein:
the transmitter is further configured to transmit a second capability value N cells cap , and
M PDCCH total,slot,μ =└N cells cap ·M PDCCH max,slot,μ ·N cells DL,μ /Σ j=0 3 (N cells,0 DL,j +2·N cells,1 DL,j )┘, where Σ j=0 3 N cells DL,j >4.
4. The UE of claim 1 , wherein:
a maximum number of CORESETs in any of the N cells,0 DL,μ cells is three including a CORESET with index 0; and
for the N cells,1 DL,μ cells, a maximum number of CORESETs in any of the N cells DL,μ cells is five where:
a maximum number of first CORESETs is three including a CORESET with index 0, and
a maximum number of second CORESETs is three including a CORESET with index 0.
5. The UE of claim 1 , wherein the receiver is further configured to receive:
first PDCCH candidates in first CORESETs of a first cell,
second PDCCH candidates in first CORESETs of a second cell, and
a physical downlink shared channel (PDSCH) on the second cell that is scheduled by a downlink control information (DCI) format provided either by a PDCCH candidate from the first PDCCH candidates or by a PDCCH candidate from the second PDCCH candidates.
6. The UE of claim 1 , wherein:
the receiver is further configured to receive a PDCCH that provides a downlink control information (DCI) format;
the processor is further configured to determine, based on a field of the DCI format, a transmission configuration indication (TCI) state for each of the second CORESETs of a cell from the N cells,1 DL,μ cells; and
the receiver is further configured to receive PDCCHs in a CORESET from the second CORESETs of the cell according to the determined TCI state.
7. The UE of claim 6 , wherein the PDCCH is received in a CORESET from the first CORESETs or in a CORESET with index 0.
8. A base station comprising:
a receiver configured to receive a first capability value;
a transmitter configured to transmit:
a configuration of N cells DL,μ downlink cells scheduled by physical downlink control channels (PDCCHs) with a sub-carrier spacing (SCS) configuration μ; and
a configuration of a first group index for first control resource sets (CORESETs) and of a second group index for second CORESETs per cell for N cells,1 DL,μ cells from the N cells DL,μ ; and
a processor, operably connected to the transmitter, configured to determine a total number M PDCCH total,slot,μ of PDCCH candidates per slot based on the first capability value, a number of the N cells,1 DL,μ cells, and a number of N cells,0 DL,μ for each SCS configuration μ, where N cells,0 DL,μ =N cells DL,μ −N cells,1 DL,μ .
9. The base station of claim 8 , wherein:
a maximum number of CORESETs in any of the N cells,0 DL,μ cells is three including a CORESET with index 0; and
for the N cells,1 DL,μ cells, a maximum number of CORESETs in any of the N cells,1 DL,μ cells is five where:
a maximum number of first CORESETs is three including a CORESET with index 0, and
a maximum number of second CORESETs is three including a CORESET with index 0.
10. The base station of claim 8 , wherein the transmitter is further configured to transmit:
first PDCCH candidates in first CORESETs of a first cell,
second PDCCH candidates in first CORESETs of a second cell, and
a physical downlink shared channel (PDSCH) on the second cell that is scheduled by a downlink control information (DCI) format provided either by a PDCCH candidate from the first PDCCH candidates or by a PDCCH candidate from the second PDCCH candidates.
11. The base station of claim 8 , wherein:
the processor is further configured to include, in a field of a downlink control information (DCI) format, an indication for enabling PDCCH receptions in the second CORESETs of a cell from the N cells,1 DL,μ cells;
the transmitter is further configured to:
transmit a PDCCH that provides the DCI format; and
transmit PDCCHs in the second CORESETs of the cell based on the indication.
12. The base station of claim 8 , wherein:
the processor is further configured to include, in a field of a downlink control information (DCI) format, an indication of a transmission configuration indication (TCI) state for each of the second CORESETs of a cell from the N cells,1 DL,μ cells,
the transmitter is further configured to:
transmit a PDCCH that provides the DCI format; and
transmit PDCCHs in a CORESET from the second CORESETs of the cell according to the indicated TCI state.
13. The base station of claim 12 , wherein the PDCCH is transmitted in a CORESET from the first CORESETs or in a CORESET with index 0.
14. A method for a user equipment (UE) to determine a maximum number of PDCCH candidates to receive per cell and per slot, the method comprising:
transmitting a first capability value;
receiving:
a configuration of N cells DL,μ downlink cells scheduled by physical downlink control channels (PDCCHs) with a sub-carrier spacing (SCS) configuration μ; and
a configuration of a first group index for first control resource sets (CORESETs) and of a second group index for second CORESETs per cell for N cells,1 DL,μ from the N cells DL,μ ;
determining a total number M PDCCH total,slot,μ of PDCCH candidates per slot based on the first value, a number of the N cells,1 DL,μ cells, and a number of N cells,0 DL,μ cells for each SCS configuration μ, where N cells,0 DL,μ =N cells DL,μ −N cells,1 DL,μ ; and
receiving, per cell from the N cells DL,μ cells and per slot, a number of PDCCH candidates that is not larger than the minimum of:
the total number M PDCCH total,slot,μ of PDCCH candidates per slot, and
a maximum predefined number M PDCCH max,slot,μ of PDCCH candidates per slot.
15. The method of claim 14 , further comprising:
transmitting a second capability value N cells cap , and
M PDCCH total,slot,μ =└N cells cap ·M PDCCH max,slot,μ ·N cells DL,μ /Σ j=0 3 N cells DL,j ┘, where Σ j=0 3 N cells DL,j >4.
16. The method of claim 14 , further comprising:
transmitting a second capability value N cells cap , and
M PDCCH total,slot,μ =└N cells cap ·M PDCCH max,slot,μ ·N cells DL,μ /Σ j=0 3 (N cells,0 DL,j +2·N cells,1 DL,j )┘, where Σ j=0 3 N cells DL,j >4.
17. The method of claim 14 , wherein:
a maximum number of CORESETs in any of the N cells,0 DL,μ cells is three including a CORESET with index 0; and
for the N cells DL,μ cells, a maximum number of CORESETs in any of the N cells,1 DL,μ cells is five where:
a maximum number of first CORESETs is three including a CORESET with index 0, and
a maximum number of second CORESETs is three including a CORESET with index 0.
18. The method of claim 14 , further comprising receiving:
first PDCCH candidates in first CORESETs of a first cell,
second PDCCH candidates in first CORESETs of a second cell, and
a physical downlink shared channel (PDSCH) on the second cell that is scheduled by a downlink control information (DCI) format provided either by a PDCCH candidate from the first PDCCH candidates or by a PDCCH candidate from the second PDCCH candidates.
19. The method of claim 14 , further comprising:
receiving a PDCCH that provides a downlink control information (DCI) format;
determining, based on a field of the DCI format, a transmission configuration indication (TCI) state for each of the second CORESETs of a cell from the N cells,1 DL,μ cells; and
receiving PDCCHs in a CORESET from the second CORESETs of the cell according to the determined TCI state.
20. The method of claim 19 , wherein the PDCCH reception is in a CORESET from the first CORESETs or in a CORESET with index 0.