Robust 2D beamforming with optimal loading technique

Abstract

This paper presents a robust adaptive rectangular antenna array beamforming using fixed diagonal loading (FDL) and optimal diagonal loading (ODL) techniques. Robustness of beamformer is important for practical implementation because of different uncertainties created in beamformer such as uncertainty in direction-of-arrival (DOA), imperfect antenna array calibration, near-far field effect, mutual coupling and other mismatches and modelling errors. Among different uncertainties DOA estimation error causes the most erroneous result. Numerical simulation results show that the robust technique improves the rectangular array performance, therefore improves the signal-to-noise plus interference ratio (SINR) of the beamformer. Results also show that the optimal diagonal loading (ODL) technique gives better performance than fixed diagonal loading (FDL) technique in terms of SINR.