Author(s)

Tsui-Tsai Lin^2*, Fuh-Hsin Hwang³, Juinn-Horng Deng¹

¹Department of Communication Engineering, Yuan Ze University, Taoyuan.
²Department of Electronic Engineering, National United University, Miaoli.
³Department of Optoelectronics and Communication Engineering, National Kaohsiung Normal University, Kaohsiung.

In this paper, we present a theoretical analysis of the output signal-to-interference-plus-noise ratio (SINR) for eigen-space beamformers so as to investigate the performance degradation caused by large pointing errors. For the sake of reducing such performance loss, a robust scheme, which consists of two cascaded signal processors, is proposed for adaptive beamformers. In the first stage, an algorithm possessing time efficiency is developed to adjust the direc-tion-of-arrival (DOA) estimate of the desired source. Based the achieved DOA estimate, the second stage provides an eigenspace beamformer combined with the spatial derivative constraints (SDC) to further mitigate the cancellation of the desired signal. Analysis and numerical results have been conducted to verify that the proposed scheme yields a better robustness against pointing errors than the conventional approaches.

Beamforming, Large Pointing Error, Output Signal-To-Interference-Plus-Noise Ratio (SINR), Eigenspace Beamformer, Two-Stage

Lin, T. , Hwang, F. and Deng, J. (2011) Performance Analysis on Output SINR of Robust Two-Stage Beamforming. Journal of Signal and Information Processing, 2, 37-43. doi: 10.4236/jsip.2011.21006.