A Novel Receiver Aided Beamforming Technique

Abstract:
In this paper, we propose a new receiver-aided beamforming scheme to exploit the multiuser diversity in a multiantenna broadcast channel. By introducing an appropriately designed beamforming codebook that consists of the beam matrices, we can further exploit multiuser diversity by performing beam matrix selection operation and improve system throughput. The beam matrix selection could be implemented by the aid of receivers in practical system. Beamforming codebook is generated offline and stored at the base station (BS) and every user’s receiver. Each user calculates the achievable signal to interference plus noise ratio (SINR) using the available channel state information at the receiver (CSIR), all beamforming matrices in the codebook and all beam vectors in the selected beam matrix, and then forms feedback information including the maximum SINR and the corresponding best beam matrix index and beam vector index. Based on the feedback information, the BS runs scheduling algorithm to maximize throughput. Numerical results show that this scheme can considerably improve throughput of existed random beamforming scheme with only a few more bits feedback overhead.