Iterative Limited Feedback Beamforming for MIMO Ad-hoc Networks

In wireless MIMO ad-hoc networks, channel reciprocity is assumed to optimize transmit and receive beamformers in conventional beamforming algorithms. But, when channels between nodes are not reciprocal, it is a huge burden to the feedback channel to inform a transmitting node of the channel state information. In this paper, we propose a distributed beamforming scheme with limited feedback for non-reciprocal channels in MIMO ad-hoc networks. In the proposed scheme, all transmitting and receiving node pairs working at the same resource perform an iterative sequential beamformer update in a distributed way. Numerical results are also presented to verify the performance of the proposed scheme.