Control signaling design for improved resource utilization

1. A user equipment (UE) comprising:

a transceiver configured to:

transmit capability information for physical downlink control channel (PDCCH) receptions on a downlink (DL) cell according to at least two (X,Y) combinations, wherein the PDCCH receptions are in any symbols of a span, a length of a span is up to Y symbols in a slot, and a number of symbols between first symbols of two consecutive spans is X; and

receive configuration information of one or more search space sets for the PDCCH receptions on the DL cell; and

a processor operably coupled with the transceiver, the processor configured to, in case that the UE indicates a capability to monitor at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a value of X for one or more of the at least two combinations, determine to monitor the at least one PDCCH according to a combination with a largest value of X from the one or more combinations,

wherein a larger maximum number of PDCCH candidates is associated with a larger value of X, and

wherein the transceiver is further configured to receive the at least one PDCCH on the DL cell based on the configuration information.

2. The UE of claim 1 , wherein, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least the larger value of X for the at least two combinations, the processor is configured to determine to monitor the at least one PDCCH according to a first combination with the larger value of X for the at least two combinations.

3. The UE of claim 1 , wherein, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a smaller value of X for the at least two combinations, the processor is configured to determine to monitor the at least one PDCCH according to a second combination with the smaller value of X for the at least two combinations.

4. The UE of claim 1 , wherein the processor is further configured to determine to monitor the at least one PDCCH according to the combination that is associated with the larger maximum number of PDCCH candidates and a larger maximum number of non-overlapping control channel elements (CCEs) per span.

5. The UE of claim 1 , wherein:

the transceiver is configured to receive a configuration of N cells DL,j DL cells,

scheduling on the N cells DL,j DL cells is by corresponding PDCCH receptions having a sub-cells carrier spacing (SCS) value of 2 j ·15 kHz, j=0, . . . J, where J is a predetermined number of SCS values, and

the processor is configured to determine the maximum number of PDCCH candidates and a maximum number of non-overlapped CCEs to

M PDCCH total,X,μ =└N cells cap ·M PDCCH max,X,μ ·N cells DL,X,μ /Σ j=0 J N cells DL,j ┘

and

C PDCCH total,X,μ =└N cells cap ·C PDCCH max,X,μ ·N cells DL,X,μ /Σ j=0 J N cells DL,j ┘ respectively,

where:

N cells cap is a number of DL cells configured to or indicated by the UE,

M PDCCH max,X,μ C PDCCH max,X,μ are respectively a maximum number of PDCCH candidates and a maximum number of non-overlapped CCEs that the UE can monitor for a span gap of X symbols for subcarrier spacing (SCS) configuration μ,

N cells DL,X,μ is a number of cells from N cells DL,μ DL cells where the UE monitors PDCCH according to a span gap of X symbols, and

└ ┘ is a ‘floor’ function that rounds a number to a next smaller integer.

6. The UE of claim 1 , wherein:

the transceiver is further configured to receive:

PDCCHs on the DL cell according to the search space sets,

a configuration of second search space sets for PDCCH receptions on a second DL cell,

PDCCHs on the second DL cell according to the second search space sets, and

first and second physical downlink shared channels (PDSCHs) on the DL cell, the first and second PDSCHs providing first and second transport blocks (TBs), respectively, wherein the first PDSCH is scheduled by a first downlink control information (DCI) format provided by a PDCCH reception on the DL cell, the first DCI format includes a carrier indicator field (CIF) with a value 0, the second PDSCH is scheduled by a second DCI format provided by a PDCCH reception on the second DL cell, and the second DCI format includes a CIF with a value other than 0; and

wherein the transceiver is further configured to:

transmit, on a first cell, a physical uplink control channel (PUCCH) with hybrid automatic repeat request acknowledgement (HARQ-ACK) information for the first TB, and

transmit, on a second cell, a PUCCH with HARQ-ACK information for the second TB, wherein the first and second DCI formats include a field indicating a cell for a PUCCH transmission.

7. Abase station comprising:

a transceiver configured to:

receive, from a user equipment (UE), capability information for physical downlink control channel (PDCCH) receptions on a downlink (DL) cell according to at least two (X,Y) combinations, wherein the PDCCH receptions are in any symbols of a span, a length of a span is up to Y symbols in a slot, and a number of symbols between first symbols of two consecutive spans is X, and

transmit configuration information of one or more search space sets for the PDCCH receptions on the DL cell; and

a processor operably coupled with the transceiver, the processor configured to determine to transmit at least one PDCCH to the UE,

wherein, in case that the UE indicates a capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a value of X for one or more of the at least two combinations, a combination to be used for PDCCH monitoring is determined as one with a largest value of X from the one or more combinations,

wherein a larger maximum number of PDCCH candidates is associated with a larger value of X, and

wherein the transceiver is further configured to transmit, to the UE, the at least one PDCCH on the DL cell based on the configuration information.

8. The base station of claim 7 , wherein, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least the larger value of X for the at least two combinations, the combination to be used for PDCCH monitoring is determined as a first combination with the larger value of X for the at least two combinations.

9. The base station of claim 7 , wherein, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a smaller value of X for the at least two combinations, the combination to be used for PDCCH monitoring is determined as a second combination with the smaller value of X for the at least two combinations.

10. The base station of claim 7 , wherein the at least one PDCCH is determined according to the combination that is associated with the larger maximum number of PDCCH candidates and a larger maximum number of non-overlapping control channel elements (CCEs) per span.

11. The base station of claim 7 , wherein:

the transceiver is configured to transmit a configuration of N cells DL,j DL cells,

scheduling on the N cells DL,j DL cells is by corresponding PDCCH receptions having a sub-carrier spacing (SCS) value of 2 j ·15 kHz, j=0, . . . J, where J is a predetermined number of SCS values, and

the maximum number of PDCCH candidates and a maximum number of non-overlapped CCEs are determined to M PDCCH total,X,μ =└N cells cap ·M PDCCH max,X,μ ·N cells DL,X,μ /Σ j=0 J N cells DL,j ┘ and C PDCCH total,X,μ =└N cells cap ·C PDCCH max,X,μ ·N cells DL,X,μ /Σ j=0 J N cells DL,j ┘ respectively,

where:

N cells cap is a number of DL cells configured to or indicated by the UE,

M PDCCH max,X,μ and C PDCCH max,X,μ are respectively a maximum number of PDCCH candidates and a maximum number of non-overlapped CCEs that the UE can monitor for a span gap of X symbols for subcarrier spacing (SCS) configuration μ,

N cells DL,X,μ is a number of cells from N cells DL,μ DL cells where the UE monitors PDCCH according to a span gap of X symbols, and

└ ┘ is a ‘floor’ function that rounds a number to a next smaller integer.

12. A method for receiving physical downlink control channels (PDCCHs) by a user equipment (UE), the method comprising:

transmitting capability information for physical downlink control channel (PDCCH) receptions on a downlink (DL) cell according to at least two (X,Y) combinations, wherein the PDCCH receptions are in any symbols of a span, a length of a span is up to Y symbols in a slot, and a number of symbols between first symbols of two consecutive spans is X;

receiving configuration information of one or more search space sets for the PDCCH receptions on the DL cell; and

in case that the UE indicates a capability to monitor at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a value of X for one or more of the at least two combinations, determining to monitor the at least one PDCCH according to a combination with a largest value of X from the one or more combinations, wherein a larger maximum number of PDCCH candidates is associated with a larger value of X; and

receiving the at least one PDCCH on the DL cell based on the configuration information.

13. The method of claim 12 , further comprising, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least the larger value of X for the at least two combinations, determining to monitor the at least one PDCCH according to a first combination with the larger value of X for the at least two combinations.

14. The method of claim 12 , further comprising, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a smaller value of X for the at least two combinations, determining to monitor the at least one PDCCH according to a second combination with the smaller value of X for the at least two combinations.

15. The method of claim 12 , wherein determining to monitor the at least one PDCCH further comprises determining to monitor the at least one PDCCH according to the combination that is associated with the larger maximum number of PDCCH candidates and a larger maximum number of non-overlapping control channel elements (CCEs) per span.

16. The method of claim 12 , further comprising:

receiving a configuration of N cells DL,j DL cells, wherein scheduling on the N cells DL,j DL cells is by corresponding PDCCH receptions having a sub-carrier spacing (SCS) value of 2 j ·15 kHz, j=0, . . . J, where J is a predetermined number of SCS values; and

determining the maximum number of PDCCH candidates and a maximum number of non-overlapped CCEs to M PDCCH total,X,μ =└N cells cap ·M PDCCH max,X,μ ·N cells DL,X,μ /Σ j=0 J N cells DL,j ┘ and C PDCCH total,X,μ =└N cells cap ·C PDCCH max,X,μ ·N cells DL,X,μ /Σ j=0 J N cells DL,j ┘ respectively,

where:

N cells cap is a number of DL cells configured to or indicated by the UE,

M PDCCH max,X,μ and C PDCCH max,X,μ are respectively a maximum number of PDCCH candidates and a maximum number of non-overlapped CCEs that the UE can monitor for a span gap of X symbols for subcarrier spacing (SCS) configuration μ,

N cells DL,X,μ is a number of cells from N cells DL,μ DL cells where the UE monitors PDCCH according to a span gap of X symbols, and

└ ┘ is a ‘floor’ function that rounds a number to a next smaller integer.

17. The method of claim 12 , further comprising:

receiving PDCCHs on the DL cell according to the search space sets;

receiving a configuration of second search space sets for PDCCH receptions on a second DL cell;

receiving PDCCHs on the second DL cell according to the second search space sets;

receiving first and second physical downlink shared channels (PDSCHs) on the DL cell, the first and second PDSCHs providing first and second transport blocks (TBs), respectively, wherein the first PDSCH is scheduled by a first downlink control information (DCI) format provided by a PDCCH reception on the DL cell, the first DCI format includes a carrier indicator field (CIF) with a value 0, the second PDSCH is scheduled by a second DCI format provided by a PDCCH reception on the second DL cell, and the second DCI format includes a CIF with a value other than 0;

transmitting, on a first cell, a physical uplink control channel (PUCCH) with hybrid automatic repeat request acknowledgement (HARQ-ACK) information for the first TB; and

transmitting, on a second cell, a PUCCH with HARQ-ACK information for the second TB, wherein the first and second DCI formats include a field indicating a cell for a PUCCH transmission.

18. A method for transmitting physical downlink control channels (PDCCHs) by a base station, the method comprising:

receiving, from a user equipment (UE), capability information for physical downlink control channel (PDCCH) receptions on a downlink (DL) cell according to at least two (X,Y) combinations, wherein the PDCCH receptions are in any symbols of a span, a length of a span is up to Y symbols in a slot, and a number of symbols between first symbols of two consecutive spans is X;

transmitting configuration information of one or more search space sets for the PDCCH receptions on the DL cell; and

transmitting, to the UE, at least one PDCCH on the DL cell based on the configuration information,

wherein, in case that the UE indicates a capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a value of X for one or more of the at least two combinations, a combination to be used for PDCCH monitoring is determined as one with a largest value of X from the one or more combinations, and

wherein a larger maximum number of PDCCH candidates is associated with a larger value of X.

19. The method of claim 18 , wherein, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least the larger value of X for the at least two combinations, the combination to be used for PDCCH monitoring is determined as a first combination with the larger value of X for the at least two combinations.

20. The method of claim 18 , wherein, in case that the UE indicates the capability to monitor the at least one PDCCH according to the at least two combinations and the UE is configured the one or more search space sets with first symbols of consecutive spans separated by at least a smaller value of X for the at least two combinations, the combination to be used for PDCCH monitoring is determined as a second combination with the smaller value of X for the at least two combinations.