Design and analysis of low-complexity blind beam steering scheme for receive beamform

The complexity of beamforming, such as complexity complex weighting and combining process, are extremely important for implementation. This work presents a low complexity time-domain statistic noise suppression and hierarchical beam search algorithm to improve performance in receivers. For SIMO-OFDM systems, the complexity of the hierarchical beam search algorithm is O(n2log2n). This work proposes a simple hierarchical beam search to find the best steering vector. Through performance evaluation, the BER performance is significantly improved with about 3dB under 10^-5 BER in the case that L1=6 and L2=2 compared to that in the case L1=4 and L2=2. Besides, the BER performance is already quietly close to that achieved by the ideal beamform in the case of L1=6 and L2=4. This setting is a good choice which achieves a good tradeoff between the performance and the computational complexity. In addition, this algorithm is well-matched to different specifications.