Method and apparatus for calibration and channel state feedback to support transmit beamforming in a mimo system

A method for calibration to support transmit beamforming in multiple-input multiple-output (MIMO) wireless communications for channel state feedback to support transmit beamforming, the method comprising:

• a first STA sending a channel state feedback request to a second STA;
• the second STA sending a sounding packet to the first STA;
• the first STA receiving the sounding packet and performing a channel measurement with the sounding packet;
• and
• the first STA calculating a steering matrix for transmit beamforming based on the channel measurement.

A station (STA) configured to obtain channel state feedback to support transmit beamforming in a multiple-input multiple-output (MIMO) wireless communication system, the STA comprising:

• a plurality of antennas;
• a channel estimator for generating a channel estimate based on a sounding packet transmitted by a communication peer;
• and
• a processor configured to send a channel state feedback request to a communication peer and calculate a steering matrix for transmit beamforming based on the channel estimate.