Abstract:

A cooperative beamforming scheme based on relay selection (S-BF) is presented. To minimize the probability of the end-to-end average Bit Error Rate (BER), a near-optimal threshold is determined to select those “appropriate” relay nodes participating in beamforming. This method guarantees that the energy is only allocated to those “appropriate” relay nodes, and accordingly improves the diversity in the cooperative beamforming. The number of selection searches is equivalent to the number of relay nodes, which will decrease the complexity of the selection procedure. Monte Carlo simulation results demonstrate that the proposed scheme can achieve an essential improvement in terms of BER performance over All Participate cooperative beamforming (AP-BF), and high energy efficiency for energy-constrained networks.

Key words: communication, amplify-and-forward (AF), cooperative beamforming, relay selection, energy efficiency