Method and apparatus for high-resolution CSI reporting in advanced wireless communication systems
Method and apparatus for high-resolution channel state information (CSI) reporting in advanced wireless communication systems. A method of operating a user equipment (UE) includes selecting, from a full basis set comprising N bases for a plurality of v layers, an intermediate basis set comprising N′ bases that are common among the plurality of v layers and selecting, from the selected intermediate basis set, a basis subset comprising M l bases for each layer l of the plurality of v layers. The method further includes transmitting, to a base station (BS), indices of the N′ bases included in the selected intermediate basis set and indices of the M l bases included in the selected basis subsets. N, N′, and M l are positive integers; N′<N; M l <N′; l∈{0, 1 . . . , v−1}; and v is a rank value.
1. A user equipment (UE), the UE comprising:
a transceiver; and
a processor configured to:
receive, via the transceiver, configuration information including information for a channel state information (CSI) report, the configuration information indicating a codebook type,
identify an intermediate basis set including N′ basis vectors common to a plurality of layers, based on a full basis set including N basis vectors, and
identify a basis subset including M l basis vectors each specific to a layer l of the plurality of layers, based on the intermediate basis set, and
transmit, via the transceiver, the CSI report including a pre-coding matrix indicator (PMI) regarding the N′ basis vectors included in the intermediate basis set and the M l basis vectors included in the basis subset, to a base station,
wherein N, N′, and M l are positive integers, N′<N, M l <N′, and l is a value corresponding to a number of the one or more layers.
2. The UE of claim 1 , wherein the PMI includes indicators indicating indices of the N′ basis vectors included in the intermediate basis set.
3. The UE of claim 1 , wherein the PMI includes indicators indicating indices of the M l basis vectors included in the basis subset.
4. The UE of claim 1 , wherein a value of the M l basis vectors of the basis subset is determined based on the configuration information received from the BS.
5. The UE of claim 1 , wherein the codebook type is set to type 2 based on the configuration information.
6. The UE of claim 1 , wherein the codebook type corresponds to a total number of precoding matrices indicated by the PMI.
7. The UE of claim 1 , wherein a value of M l for each of the basis subsets is determined based on configuration information received from the BS.
8. A base station (BS), the BS comprising:
a processor; and
a transceiver configured to
transmit, to a user equipment (UE), configuration information including information for a channel state information (CSI) report, the configuration information indicating a codebook type, wherein an intermediate basis set including N′ basis vectors common to a plurality of layers is based on a full basis set including N basis vectors, wherein a basis subset including M l basis vectors each specific to a layer l of the plurality of layers is based on the intermediate basis set, and
receive, from the UE, the CSI report including a pre-coding matric indicator (PMI) regarding the basis vectors included in the intermediate basis set and the M l basis vectors included in the basis subset, from the UE,
wherein N, N′, and M l are positive integers, N′<N, M l <N′, and l is a value corresponding to a number of the one or more layers.
9. The BS of claim 8 , wherein the PMI includes indicators indicating indices of the N′ basis vectors included in the intermediate basis set.
10. The BS of claim 8 , wherein the PMI includes indicators indicating indices of the M l basis vectors included in the basis subset.
11. The BS of claim 8 , wherein a value of the M l basis vectors of the basis subset is determined based on the configuration information received from the BS.
12. The BS of claim 8 , wherein the codebook type is set to type 2 based on the configuration information.
13. The BS of claim 8 , wherein the codebook type corresponds to a total number of precoding matrices indicated by the PMI.
14. The BS of claim 8 , wherein a value of M l for each of the basis subsets is indicated in configuration information transmitted by the transceiver to the UE.
15. A method for operating a user equipment (UE), the method comprising:
receiving configuration information including information for a channel state information (CSI) report, the configuration information indicating a codebook type;
identifying an intermediate basis set including N′ basis vectors common to a plurality of layers, based on a full basis set including N basis vectors;
identifying a basis subset including M l basis vectors each specific to a layer l of the plurality of layers, based on the intermediate basis set; and
transmitting the CSI report including a pre-coding matrix indicator (PMI) regarding the N′ basis vectors included in the intermediate basis set and the M l basis vectors included in the basis subset, to a base station,
wherein N, N′, and M l are positive integers, N′<N, M l <N′, and l is a value corresponding to a number of the one or more layers.
16. The method of claim 15 , wherein the PMI includes indicators indicating the indices of the N′ basis vectors included in the intermediate basis set.
17. The method of claim 15 , wherein the PMI includes indicators indicating indices of the M l basis vectors included in the basis subset.
18. The method of claim 15 , wherein a value of the M l basis vectors of the basis subset is determined based on the configuration information received from the BS.
19. The method of claim 15 , wherein the codebook type is set to type 2 based on the configuration information.
20. The method of claim 15 , wherein the codebook type corresponds to a total number of precoding matrices indicated by the PMI.