Wireless feedback system and method

A multiple-input multiple-output (MIMO) receiver configured for providing feedback, comprising:

• logic configured to select a first codeword from a plurality of codewords in a codebook based on first channel information at a first time;
• logic configured to determine second channel information for a MIMO channel at a subsequent time;
• logic configured to select a subset codeword from a subset of codebook codewords, which corresponds to the first codeword, based on the second channel information;
• and
• logic configured to transmit a subset index for the subset codeword.

A method of receiving feedback from a multiple-input multiple-output (MIMO) receiver, the method comprising, at a MIMO transmitter:

• determining a first codeword index at a first time;
• receiving a subset codeword index at a subsequent time;
• identifying a subset codeword from a subset of codebook codewords based on the first codeword index;
• and
• applying the subset codeword to signals to be transmitted.

A multiple-input multiple-output (MIMO) transmitter configured for receiving feedback, comprising:

• logic configured to determine a first codeword index at a first time;
• logic configured to receive a subset codeword index at a subsequent time;
• logic configured to identify a subset codeword from a subset of codebook codewords based on the first codeword index;
• and
• logic configured to apply the subset codeword to signals to be transmitted.