Channel acquisition and channel state feedback for analog and digital precoding using joint optimization

A second network entity, comprising:

• one or more memories storing processor-executable code;
• and
• one or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the second network entity to:
• output, to a first network entity, a message comprising a configuration for a plurality of channel state information reference signal (CSI-RS) resources, the configuration comprising:
• a first indication of a plurality of beams associated with respective CSI-RS resources of the plurality of CSI-RS resources and a plurality of transmit antenna ports;
• and
• a second indication of an orthogonal basis associated with the plurality of beams,
• wherein each of the plurality of transmit antenna ports corresponds to a respective set of antenna elements of the second network entity, and wherein each CSI-RS resource is associated with transmission from the plurality of transmit antenna ports;
• and
• obtain a feedback report comprising a channel matrix associated with the respective sets of antenna elements corresponding to the plurality of transmit antenna ports, digital precoding information for the plurality of transmit antenna ports and analog precoding information for each of the plurality of transmit antenna ports, or a combination thereof, wherein the feedback report is based at least in part on the orthogonal basis.

A method for wireless communications at a first network entity, comprising:

• receiving a message comprising a configuration for a plurality of channel state information reference signal (CSI-RS) resources, the configuration comprising:
• a first indication of a plurality of beams associated with respective CSI-RS resources of the plurality of CSI-RS resources and a plurality of transmit antenna ports;
• and
• a second indication of an orthogonal basis associated with the plurality of beams,
• wherein each of the plurality of transmit antenna ports corresponds to a respective set of antenna elements of a second network entity, and wherein each CSI-RS resource is associated with transmission from the plurality of transmit antenna ports;
• and
• transmitting a feedback report based at least in part on measurements of the plurality of transmit antenna ports over the plurality of CSI-RS resources and on the orthogonal basis, the feedback report comprising a channel matrix associated with the respective sets of antenna elements corresponding to the plurality of transmit antenna ports, digital precoding information for the plurality of transmit antenna ports and analog precoding information for each of the plurality of transmit antenna ports, or a combination thereof.

A method for wireless communications at a second network entity, comprising:

• outputting, to a first network entity, a message comprising a configuration for a plurality of channel state information reference signal (CSI-RS) resources, the configuration comprising:
• a first indication of a plurality of beams associated with respective CSI-RS resources of the plurality of CSI-RS resources and a plurality of transmit antenna ports;
• and
• a second indication of an orthogonal basis associated with the plurality of beams,
• wherein each of the plurality of transmit antenna ports corresponds to a respective set of antenna elements of the second network entity, and wherein each CSI-RS resource is associated with transmission from the plurality of transmit antenna ports;
• and
• obtaining a feedback report comprising a channel matrix associated with the respective sets of antenna elements corresponding to the plurality of transmit antenna ports, digital precoding information for the plurality of transmit antenna ports and analog precoding information for each of the plurality of transmit antenna ports, or a combination thereof, wherein the feedback report is based at least in part on the orthogonal basis.