A plurality of phases are determined. The plurality of phases are to be applied to a plurality of transmit signals to be transmitted via a plurality of transmit antennas. Each transmit signal comprises a plurality of sub-carriers. Each phase of the plurality of phases is to be applied to a corresponding block of sub carriers in the plurality of transmit signals, and each block of sub-carriers comprises a plurality of sub-carriers that are adjacent in frequency. The plurality of phases are applied to the plurality of transmit signals to implement transmit diversity. Each phase is applied to the corresponding block of sub carriers in the plurality of transmit signals.