METHOD FOR ENHANCING MOBILE CDMA COMMUNICATIONS USING SPACE-TIME TRANSMIT DIVERSITY

摘要

PURPOSE: A method for enhancing a mobile CDMA(Code Division Multiple Access) communication using a space-time transmit diversity is provided to apply an STTD(Space-Time Transmit Diversity) scheme to angular and temporary transmit diversity to combine with a polarization interleaved switch beam to enhance the downlink WCDMA(Wideband Code Division Multiple Access) performance. CONSTITUTION: An operative gain of a switch beamformer antenna structure is transferred to a diversity gain by dividing a different angle of departure with different space-time spreading. An aiming angle of the switch beamformer antenna structure is mismatched and the phase of a pilot tone is distorted for reducing beamformer gain within a side angle spread. A spreading function is imparted to the communications signal using mutually orthogonal extended Walsh codes for even and odd bits of data.