Penalty function based 2D adaptive digital beamforming for satellite communications

摘要

Two dimentional (2D) adaptive digital beamforming is one of the promising smart antenna technologies to meet the rapidly increasing demands for more capacity of satellite communication systems. However, the conventional 2D adaptive digital beamforming algorithms have the jitter and high sidelobe problems especially when the number of antenna elements is large. In this paper, a penalty function based 2D adaptive digital beamforming algorithm is proposed to estimate the weights of 2D antenna array. A penalty function is added to the original minimum square error (MSE) function. The formulas of estimating the weights are derived using the modified MSE function. System capacity and signal-to interference ratio (SIR) of the new 2D adaptive digital beamforming algorithm for satellite communications are also analyzed. Experimental results show that the penalty function based 2D adaptive beamforming algorithm can overcome the jitter and high sidelobe problems of the conventional adaptive algorithms. Compared with the fixed beam approach, the adaptive beamforming method has higher system capacity and SIR with the tradeoff of higher computation load.