Beamspace direction finding based on the conjugate gradient algorithm
Jens Steinwandt, Rodrigo C. de Lamare, Martin Haardt · 2011
Motivated by the performance of the direction finding algorithm based on the conjugate gradient (CG) method and the advantages of operating in beamspace, we develop a new beamspace direction finding algorithm, which we refer to as the beamspace conjugate gradient (BS CG) method. The recently developed Krylov subspace-based CG direction finding algorithm utilizes a non-eigenvector basis and yields a superior resolution performance for closely-spaced sources under severe conditions. However, its computational complexity is similar to the eigenvector-based methods. In order to save computational resources, we perform a beamspace transformation, which additionally leads to significant improvements in terms of the resolution capability and the estimation accuracy. A comprehensive complexity analysis and simulation results demonstrate the excellent performance of the proposed method and show its lower computational complexity.