An efficient spatial spectrum estimation direction finding method at subarray level for coherent signal sources

An important application field about spatial spectrum estimation direction finding is phased array system. For large phased arrays at subarray level, we construct an array manifold of linear array by using of the phase center and gain of each subarray and apply this manifold to WSF algorithm. Thus a direction finding algorithm is presented. There is no essential to know the complete array manifold and to calibrate the whole array. And it is suitable for coherent signal sources. A local super-resolution direction finding within beamwidth of subarray can be obtained by this method. But by controlling the beam steering of the array, super-resolution direction finding can be applied to any direction of interest. The simulation results demonstrate the efficiency of the algorithm.