Spatial spectral estimation direction finding algorithms at subarray level for complete calibration array and partly calibration array

Phased array system is an important application field of spatial spectral estimation direction finding. In this paper two spatial spectral estimation direction finding algorithms applied to large phased array at subarray level are studied. For complete calibration array, we construct an array manifold based on subarray structure and then present a MUSIC algorithm at subarray level. Another algorithm we study is suitable for partly calibration array. It´s array manifold is constructed by using of the phase center and gain of each subarray. This algorithm doesn´t need to calibrate the whole array. So it can reduce the cost of the hardware and software. But the limitation is that its super-resolution direction finding can be achieved only within beamwidth of the array. We analyses and compare the two algorithms by simulations. The simulation results demonstrate the efficiency of the presented algorithms.