Method and apparatus for codebook design and signaling

A base station (BS), comprising:

• a processor configured to configure a user equipment (UE) with a channel state information (CSI) reporting and a CSI reference signal (CSI-RS) resource;
• and
• a transceiver operably connected to the processor, the transceiver configured to:
• transmit configuration information for the CSI reporting and the CSI-RS, wherein the configuration information for the CSI reporting includes a codebook selection parameter and codebook parameters, wherein the codebook selection parameter corresponds to a type of codebook selected from a beamformed type and a non-precoded type, and wherein the codebook parameters indicate:
• (i) numbers of ports for a first dimension and a second dimension, wherein the numbers of ports are 4 or 8, and
• (ii) oversampling factors for the first dimension and the second dimension, and wherein the CSI-RS is transmitted via a configured number of CSI-RS ports,
• receive, from the UE, a CSI report generated based on the CSI-RS, the CSI report generated using a codebook determined based on the codebook selection parameter and codebook parameters corresponding to at least a subset of the received codebook parameters,
• wherein, when the codebook selection parameter has a first value, the codebook used for the CSI reporting is a first codebook derived from the codebook parameters and the CSI report is generated using the first codebook, and
• wherein, when the codebook selection parameter has a second value, the codebook used for the CSI reporting is a second codebook different than the first codebook and the CSI report is generated using the second codebook.

A method for operating a user equipment (UE), the method comprising:

• receiving, by the UE, configuration information for a channel state information (CSI) reporting from a base station (BS), wherein the configuration information for the CSI reporting includes a codebook selection parameter and codebook parameters, wherein the codebook selection parameter corresponds to a type of codebook selected from a beamformed type and a non-precoded type, and wherein the codebook parameters indicate:
• (i) numbers of ports for a first and a second dimension, and
• (ii) oversampling factors for the first dimension and the second dimension, wherein the numbers of ports are 4 or 8;
• receiving, by the UE, a CSI reference signal (CSI-RS) from the BS via a configured number of CSI-RS ports;
• measuring, by the UE, the CSI-RS;
• generating, by the UE, using a codebook determined based on the codebook selection parameter and codebook parameters corresponding to at least a subset of the received codebook parameters, a CSI report based on the measured CSI-RS;
• and
• transmitting, by the UE, the CSI report to the BS,
• wherein, when a multiple input multiple output (MIMO) type for communications with the UE is non-precoded, the codebook used for the CSI reporting is a first codebook derived from the codebook parameters and the CSI report is generated using the first codebook, and
• wherein, when the MIMO type for the communications with the UE is beamformed, the codebook used for the CSI reporting is a second codebook different than the first codebook and the CSI report is generated using the second codebook.