Method and apparatus for multiplexing partial CSI

1. A user equipment (UE) for channel state information (CSI) reporting in a wireless communication system, the UE comprising:

a transceiver configured to receive configuration information for a CSI report, wherein the configuration information configures a precoding matrix indicator (PMI) codebook and partitions the PMI codebook into first and second PMI subsets respectively indicating first and second subsets of a set of components S and wherein the set of components S is indicated to represent N 3 precoding matrices, where N 3 ≥1; and

a processor operably connected to the transceiver, the processor configured to:

determine, based on the configuration information, the CSI report comprising a first CSI part and a second CSI part, the second CSI part including the second PMI subset and partitioned into N groups, where N≥1; and

select M groups from the N groups of the second CSI part based on a resource allocation for transmission of uplink control information (UCI), where M ∈ {1, . . . , N},

wherein the transceiver is further configured to transmit, over an uplink (UL) channel, the UCI including a first UCI part and a second UCI part, the first UCI part including the first CSI part and the second UCI part including the M groups from the N groups of the second CSI part.

2. The UE of claim 1 , wherein a value of N is configured via higher layer signaling.

3. The UE of claim 1 , wherein a value of N is determined based on the second PMI subset indicating the second subset of components.

4. The UE of claim 1 , wherein for each layer l=1, . . . , v, where v≥1 is a rank value, the set of components S comprises all or some of {C 1 , . . . , C 6 }, where:

C 1 : a set of spatial domain (SD) port selection vectors {a i } and a set of frequency domain (FD) port selection vectors {b f }, where a port selection vector has one entry equal to 1 and remaining entries equal to 0,

C 2 : indices of non-zero (NZ) coefficients,

C 3 : an index of a strongest coefficient,

C 4 : a reference amplitude,

C 5 : amplitudes of NZ coefficients, and

C 6 : phases of the NZ coefficients.

5. The UE of claim 4 , wherein the sets of SD and FD port selection vectors are:

separate as {a i } i=0 L−1 and {b f } f=0 M−1 , where L and M are number of SD and FD port selection vectors, respectively, or

joint as a set of port selection vector pairs {(a i , b i )} i=0 X−1 , where X is a number of port selection vector pairs.

6. The UE of claim 4 , wherein when a value of N=1, the second CSI part is a single group (Group 0 ) that includes the second PMI subset indicating the second subset of components obtained from {C 1 , . . . , C 6 }.

7. The UE of claim 4 , wherein when a value of N=2, the second CSI part is partitioned into two groups (Group 0 , Group 1 ), each group including a part of the second PMI subset, and the second PMI subset indicating the second subset of components obtained from {C 1 , . . . , C 6 }.

8. The UE of claim 4 , wherein when a value of N=3, the second CSI part is partitioned into three groups (Group 0 , Group 1 , Group 2 ), each group including a part of the second PMI subset, and the second PMI subset indicating the second subset of components obtained from {C 1 , . . . , C 6 }, wherein Group 1 and Group 2 respectively include higher priority and lower priority elements of {C 5 , C 6 } or {C 2 , C 5 , C 6 }.

9. A base station (BS) in a wireless communication system, the BS comprising:

a processor configured to generate configuration information for a channel state information (CSI) report, wherein:

the configuration information configures a precoding matrix indicator (PMI) codebook and partitions the PMI codebook into first and second PMI subsets respectively indicating first and second subsets of a set of components S,

the set of components S is indicated to represent N 3 precoding matrices, where N 3 ≥1, and

the CSI report comprises a first CSI part and a second CSI part, the second CSI part including the second PMI subset and partitioned into N groups, where N≥1; and

a transceiver operably connected to the processor, the transceiver configured to:

transmit the CSI configuration information for the CSI report, and

receive, over an uplink (UL) channel, uplink control information (UCI), the UCI including a first UCI part and a second UCI part, the first UCI part including the first CSI part and the second UCI part including M groups from the N groups of the second CSI part, wherein the M groups from the N groups of the second CSI part are selected based on a resource allocation for transmission of the UCI, where M ∈ {1, . . . , N}.

10. The BS of claim 9 , wherein a value of N is configured via higher layer signaling.

11. The BS of claim 9 , wherein a value of N is determined based on the second PMI subset indicating the second subset of components.

12. The BS of claim 9 , wherein for each layer l=1, . . . , v, where v≥1 is a rank value, the set of components S comprises all or some of {C 1 , . . . , C 6 }, where:

C 1 : a set of spatial domain (SD) port selection vectors {a i } and a set of frequency domain (FD) port selection vectors {b f }, where a port selection vector has one entry equal to 1 and remaining entries equal to 0,

C 2 : indices of non-zero (NZ) coefficients,

C 3 : an index of a strongest coefficient,

C 4 : a reference amplitude,

C 5 : amplitudes of NZ coefficients, and

C 6 : phases of the NZ coefficients.

13. The BS of claim 12 , wherein the sets of SD and FD port selection vectors are:

separate as {a i } i=0 L−1 and {b f } f=0 M−1 , where L and M are number of SD and FD port selection vectors, respectively, or

joint as a set of port selection vector pairs {(a i , b i )} i=0 X−1 , where X is a number of port selection vector pairs.

14. The BS of claim 12 , wherein when a value of N=1, the second CSI part is a single group (Group 0 ) that includes the second PMI subset indicating the second subset of components obtained from {C 1 , . . . , C 6 }.

15. The BS of claim 12 , wherein when a value of N=2, the second CSI part is partitioned into two groups (Group 0 , Group 1 ), each group including a part of the second PMI subset, and the second PMI subset indicating the second subset of components obtained from {C 1 , . . . , C 6 }.

16. The BS of claim 12 , wherein when a value of N=3, the second CSI part is partitioned into three groups (Group 0 , Group 1 , Group 2 ), each group including a part of the second PMI subset, and the second PMI subset indicating the second subset of components obtained from {C 1 , . . . , C 6 }, wherein Group 1 and Group 2 respectively include higher priority and lower priority elements of {C 5 , C 6 } or {C 2 , C 5 , C 6 }.

17. A method for operating a user equipment (UE) for channel state information (CSI) reporting in a wireless communication system, the method comprising:

receiving configuration information for a CSI report, wherein the configuration information configures a precoding matrix indicator (PMI) codebook and partitions the PMI codebook into first and second PMI subsets respectively indicating first and second subsets of a set of components S and wherein the set of components S is indicated to represent N 3 precoding matrices, where N 3 ≥1;

determining, based on the configuration information, the CSI report comprising a first CSI part and a second CSI part, the second CSI part including the second PMI subset and partitioned into N groups, where N≥1;

selecting M groups from the N groups of the second CSI part based on a resource allocation for transmission of uplink control information (UCI), where M ∈ {1, . . . , N}; and

transmitting, over an uplink (UL) channel, the UCI including a first UCI part and a second UCI part, the first UCI part including the first CSI part and the second UCI part including the M groups from the N groups of the second CSI part.

18. The method of claim 17 , wherein a value of N is configured via higher layer signaling.

19. The method of claim 17 , wherein a value of N is determined based on the second PMI subset indicating the second subset of components.

20. The method of claim 17 , wherein for each layer l=1, . . . , v, where v≥1 is a rank value, the set of components S comprises all or some of {C 1 , . . . , C 6 }, where:

C 1 : a set of spatial domain (SD) port selection vectors {a i } and a set of frequency domain (FD) port selection vectors {b f }, where a port selection vector has one entry equal to 1 and remaining entries equal to 0,

C 2 : indices of non-zero (NZ) coefficients,

C 3 : an index of a strongest coefficient,

C 4 : a reference amplitude,

C 5 : amplitudes of NZ coefficients, and

C 6 : phases of the NZ coefficients.