Patent ID: 7826547

Claim:
A method for generating a preamble of a frame for a multiple input multiple output (MIMO) wireless communication, the method comprises: for a first transmit antenna of the MIMO communication: generating a legacy preamble portion for the frame in accordance with a first legacy standard wireless communication protocol, wherein the legacy preamble portion includes at least a first training sequence and a second training sequence and a signal field, wherein the signal field is generated in accordance with the legacy wireless communication protocol and includes an indication of a duration of the frame; and generating a current protocol preamble portion for the frame in accordance with a second current standard wireless communication protocol of the MIMO wireless communication; for at least a second antenna of the MIMO communication: generating a cyclically shifted legacy preamble portion for the frame, wherein the cyclically shifted legacy preamble portion includes a cyclically shifted first training sequence and a cyclically shifted second training sequence and a cyclically shifted signal field, wherein the cyclically shifted first training sequence the cyclically shifted second training sequence is time-shifted with respect to the first training sequence by a fraction of duration of the legacy preamble portion, and wherein the cyclically shifted second training sequence is time-shifted with respect to the second training sequence by the fraction of duration of the legacy preamble portion, and wherein the cyclically shifted signal field is in accordance with the legacy wireless communication protocol and includes the indication of the duration of the frame; and generating a second current protocol preamble portion for the frame in accordance with the second current standard wireless communication protocol of the MIMO wireless communication.