Hybrid algorithms for adaptive array systems
D. Papadimitriou, Ioannis O. Vardiambasis · International Conference on Telecommunications · 2005
In recent years, mobile communications have caused an explosive growth to the number of wireless users. This growth has triggered an enormous demand not only for capacity but also for better coverage and quality of services with priority on interference cancellation. This need lead scientists in using adaptive array antennas. The aim of this paper is to study the adaptive beamforming approaches as part of smart antenna technology. This work's focus is on the investigation of various adaptive algorithms and their ability to automatically respond to an unknown interference environment by steering nulls and reducing side lobe levels in the direction of interference, while keeping desired signal beam characteristics. The investigation covers three well known algorithms [Sample Matrix Inversion (SMI), Least Mean Squares (LMS), Normalized Least Mean Squares (N-LMS)], along with the combination of SMI and LMS and the combination of SMI and NLMS, which are proposed here.