Configurations and feedback schemes for compressed channel state information (csi)

An apparatus for wireless communication by a User Equipment (UE), comprising:

• at least one processor configured to:
• determine a constraint on a total number of transfer domain coefficients to be reported for compressed Channel State Information (CSI) feedback by the UE for a plurality of beams identified for the feedback, wherein each transfer domain coefficient is associated with amplitude information and phase information, wherein the transfer domain is based at least on a set of DFT (Discrete Fourier Transform) bases or a set of DCT (Discrete Cosine Transfer) bases;
• select from a transfer domain coefficient compression matrix, based on the constraint, a set of one or more transfer domain coefficients to report for each of the beams;
• report information indicating a number of selected transfer domain coefficients in the set of transfer domain coefficients for each beam and a location of each transfer domain coefficient within the transfer domain coefficient compression matrix;
• and
• report at least the amplitude and phase information for the selected coefficients;
• and
• a memory coupled to the at least one processor.

A method for wireless communication by a Base Station (BS), comprising:

• transmitting reference signals to be used by a User Equipment (UE) for Channel State Information (CSI) feedback to the BS;
• determining a constraint on a total number of transfer domain coefficients to be reported for compressed CSI feedback by a UE for a plurality of beams identified for the feedback, wherein each transfer domain coefficient is associated with amplitude information and phase information, wherein the transfer domain is based at least on a set of DFT (Discrete Fourier Transform) bases or a set of DCT (Discrete Cosine Transfer) bases;
• receiving as part of CSI feedback:
• information indicating a number of transfer domain coefficients in a set of transfer domain coefficients for each beam, the transfer domain coefficients selected from a transfer domain coefficient compression matrix based on the constraint;
• a location of each selected transfer domain coefficient within the transfer domain coefficient compression matrix;
• and
• at least the amplitude and phase information for the selected coefficients;
• and
• adjusting a configuration of one or more antennas of the BS based on the received feedback.

An apparatus for wireless communication by a Base Station (BS), comprising:

• at least one processor configured to:
• transmit reference signals to be used by a User Equipment (UE) for Channel State Information (CSI) feedback to the BS;
• determine a constraint on a total number of transfer domain coefficients to be reported for compressed CSI feedback by a UE for a plurality of beams identified for the feedback, wherein each transfer domain coefficient is associated with amplitude information and phase information, wherein the transfer domain is based at least on a set of DFT (Discrete Fourier Transform) bases or a set of DCT (Discrete Cosine Transfer) bases;
• receive as part of CSI feedback:
• information indicating a number of transfer domain coefficients in a set of transfer domain coefficients for each beam, the transfer domain coefficients selected from a transfer domain coefficient compression matrix based on the constraint;
• a location of each selected transfer domain coefficient within the transfer domain coefficient compression matrix;
• and
• at least the amplitude and phase information for the selected coefficients;
• and
• adjust a configuration of one or more antennas of the BS based on the received feedback;
• and
• a memory coupled to the at least one processor.