Generalized beamforming for MIMO systems with limited transmitter information

In this work, we investigate the outage performance of beamforming schemes in wireless systems equipped with multiple transmit and receive antennas. In particular, we analyze the outage performance of unit rank beamforming in the presence of finite rate channel feedback at the transmitter. Further, we present finite size beamformer codebook constructions which result in near-optimal outage performance for unit rank beamforming. The constructions obtained for the unit rank beamforming scheme are then extended to higher rank beamforming schemes with quantized channel information. We show that significant performance improvements as well as reduction in decoding complexity can result from a small number of feedback bits.