Method and apparatus for multiplexing partial CSI

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 N3 precoding matrices, where N3≥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}.

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 N3 precoding matrices, where N3≥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.