BEAMSPACE-TIME CODING BASED ON CHANNEL QUALITY FEEDBACK

摘要

METHODS AND APPARATUS FOR INCREASING DIVERSITY GAIN AT A RECEIVER (380) BY APPLYING BEAMFORMING TO TRANSMIT DIVERSITY SPACE-TIME CODED SIGNALS. A TRANSMIT SIGNAL IS SPACE-TIME CODED OVER A PLURALITY OF SPACE-TIME ANTENNA GROUPS (340), WITH EACH SPACE-TIME ANTENNA GROUP ASSOCIATED WITH A SPECIFIC SPACE-TIME CODE. THE SIGNAL AT EACH SPACE-TIME ANTENNA GROUP (340) IS BEAMFORMED OVER THE PLURALITY OF ANTENNA IN THE SPACE-TIME ANTENNA GROUP (340). EACH OF THE PLURALITY OF ANTENNA IN A SPACE-TIME ANTENNA GROUP (340) IS WEIGHTED WITH A DISTINCT WEIGHT, RELATIVE TO THE OTHER ANTENNA IN THE SPACE-TIME GROUP. THE BEAMFORMING WEIGHTS CAN VARY BASED ON A CHANNEL QUALITY FEEDBACK INDICATION FROM A RECEIVER (380). THE AMPLITUDE, PHASE, OR A COMBINATION OF AMPLITUDE AND PHASE OF EACH WEIGHT OR OF A VECTOR OF MULTIPLE WEIGHTS CAN VARY AS A FUNCTION OF THE CHANNEL QUALITY INDICATION IN ORDER TO IMPROVE THE QUALITY OF THE RECEIVED SIGNAL.