Csi reporting

A base station (BS), comprising

• a processor;
• and
• a transceiver operably coupled to the processor, the transceiver configured to:
• transmit information about a channel state information (CSI) report, the CSI report indicating a matrix
• C
• =
• [
• c
• 1
• ,
• 1
• c
• 1
• ,
• 2
• …
• c
• 1
• ,
• N
• SB
• c
• 2
• ,
• 1
• c
• 2
• ,
• 2
• …
• c
• 2
• ,
• N
• SB
• ⋮
• ⋮
• ⋱
• ⋮
• c
• N
• port
• ,
• 1
• c
• N
• port
• ,
• 2
• …
• c
• N
• port
• ,
• N
• SB
• ]
• represented as
• C
• =
• ∑
• l
• =
• 1
• L
• ⁢
• λ
• l
• ⁢
• v
• l
• ⁢
• u
• l
• H
• using triples (λl, vl, ul), where:
• vl is a column vector of length Nport,
• ul is a column vector of length NSB,
• λl is a scalar number,
• Nport is a number of antenna ports, and
• NSB is a number of subbands (SBs);
• and
• receive the CSI report,
• wherein the CSI report is based on M datasets, where M≥1 and the M datasets are based on the triples (λl, vl, ul).

A method performed by a user equipment (UE), the method comprising:

• receiving information about a channel state information (CSI) report, the CSI report indicating a matrix
• C
• =
• [
• c
• 1
• ,
• 1
• c
• 1
• ,
• 2
• …
• c
• 1
• ,
• N
• SB
• c
• 2
• ,
• 1
• c
• 2
• ,
• 2
• …
• c
• 2
• ,
• N
• SB
• ⋮
• ⋮
• ⋱
• ⋮
• c
• N
• port
• ,
• 1
• c
• N
• port
• ,
• 2
• …
• c
• N
• port
• ,
• N
• SB
• ]
• represented as
• C
• =
• ∑
• l
• =
• 1
• L
• ⁢
• λ
• l
• ⁢
• v
• l
• ⁢
• u
• l
• H
• using triples (λl, vl, ul), where:
• vl is a column vector of length Nport,
• ul is a column vector of length NSB,
• λl is a scalar number,
• Nport is a number of antenna ports, and
• NsB is a number of subbands (SBs);
• determining the CSI report;
• and
• transmitting the CSI report,
• wherein the CSI report is based on M datasets, where M≥1 and the M datasets are based on the triples (λl, vl, ul).