A comparative study of Minimum Variance Distortionless Response beamforming, Linearly Constrained Minimum Variance beamforming and metaheuristic solved null-steering beamforming

Abstract

Digital beamforming is of paramount significance in addressing wireless communication systems’ capacity enhancement. Among well established digital beamforming mechanisms are Minimum Variance Distortionless Response (MVDR) and Linearly Constrained Minimum Variance (LCMV) techniques. It would be worth- while to establish the relative performance of the afore-mentioned techniques in beamforming in various situations. In this paper, MVDR and LCMV techniques performance comparison is addressed from the perspective of narrowband beamforming (in reception mode), with the variation parameter being signal/ interferer spatial separation. The LCMV beamformer has been constrained to yield nulls in interferer Direction of Arrivals (DoAs). Also studied is a Particle Swarm Optimization (PSO) solved null-steering beamformer. It is established that the PSO solved null-steering beamformer out-performs the LCMV and MVDR techniques. MATLAB software has been used as the simulation tool. Keywords—Digital beamforming, Linearly Constrained Minimum Variance, Minimum Variance Distortionless Response, Null steering