Beamformer bank optimization for true time delay beam-space processing

The authors examine optimization of the antenna array beamformer bank for a technique to apply coherent signal subspace processing in the beam-space of a bank of true time delay beamformers. This technique offers computational expense advantages over element-space methods, Mean Square Error (MSE) performance similar to wideband coherent subspace techniques and is frequency invariant. This article reports on simulation experiments to improve the true time delay beamformer bank configuration so as to optimize MSE performance of source direction resolution for closely spaced wideband sources. Simulations include pattern search, genetic algorithm and simulated annealing global optimization methods. Results indicate that performance can be significantly improved by applying these methods to the beamformer bank design.