Patent ID: 8670504

Claim:
A method for providing transmit diversity, the method comprising: generating a plurality of space-time encoded signals from a transmit signal, wherein each space-time encoded signal is associated with a distinct space-time antenna group that comprises multiple antennas; receiving a channel quality indication from a first device, wherein receiving the channel quality indication comprises receiving a signal based on a sum of magnitude square of respective channel estimates; generating at least one weight vector at a second device based on the channel quality indication, wherein generating the at least one weight vector comprises adjusting a phase of a weight in a weight vector without adjusting an amplitude of the weight until the phase is optimized, and wherein generating the at least one weight vector further comprises selecting weights for a weight vector from a predetermined constellation of weights, wherein the constellation of weights comprises a first plurality of weights positioned substantially uniformly about a first circle having a first radius and a second plurality of weights positioned substantially uniformly about a second circle having a second radius, wherein the second radius is larger than the first radius; and beamforming, at the second device, by using the channel quality indication from the first device, the plurality of space-time encoded signals, wherein beamforming a particular space-time encoded signal comprises dividing that space-time encoded signal into multiple duplicate signal streams, separately weighting the multiple duplicate signal streams and providing the weighted signal streams to different antennas in the associated antenna group.