Differential channel state information (CSI) reporting for higher resolution CSI

A method for wireless communications by a base station (BS), comprising:

• receiving one or more first feedback components associated with first channel state information (CSI) feedback;
• receiving one or more second feedback components associated with at least one second CSI feedback;
• and
• determining a precoding to use for multiple input multiple output (MIMO) communications based on the one or more first feedback components and the one or more second feedback components.

An apparatus for wireless communication, comprising:

• a receiver configured to receive a channel state information reference signal (CSI-RS);
• at least one processor configured to:
• determine, for a first CSI feedback stage, one or more first feedback components associated with first CSI feedback based on the CSI-RS;
• and
• determine, for at least one second CSI feedback stage, one or more second feedback components associated with at least one second CSI feedback based in part on the one or more first feedback components, wherein the first CSI feedback has a lower resolution than the at least one second CSI feedback;
• a transmitter configured to report the one or more first feedback components and the one or more second feedback components;
• and
• a memory coupled to the at least one processor.

An apparatus for wireless communication, comprising:

• a receiver configured to:
• receive one or more first feedback components associated with first channel state information (CSI) feedback;
• and
• receive one or more second feedback components associated with at least one second CSI feedback;
• at least one processor configured to determine a precoding to use for multiple input multiple output (MIMO) communications based on the one or more first feedback components and the one or more second feedback components;
• and
• a memory coupled to the at least one processor.