An Adaptive Low Rank Algorithm for Semispherical Antenna Arrays

Adaptive algorithms have been applied in beam-forming applications with adaptive linear and planar arrays. In this paper, we are concerned with adaptive beamforming algorithms for 3D semispherical arrays. We present a low rank adaptive algorithm, which we call the 3D low rank recursive least squares approximate power iteration. The algorithm uses a high performance subspace tracker integrated with a low rank RLS beamformer. The algorithm is computationally efficient compared to the RLS beamformer with better steady state performance and, in certain situations, equally fast convergence. The algorithm is evaluated in terms of computational complexity and adaptation speed with comparative results to the RLS beamformer.