Enhanced DOA Estimation for Moving Platform based Distributed Phased Array

Moving platform based distributed phased array (MDPA) promises a power, resolution and flexibility enhanced radar or communication system while direction of arrival (DOA) estimation is one of the most fundamental applications. However, the ultra-long spacing among each node will generate severe grating lobes. And the isolated nodes will introduce synchronization errors including gain error, phase error and position error. Such problems will impede DOA estimation performance for most existing methods. Here, we find the platform motion itself can be utilized to construct a virtual array to reduce the impact of grating lobes. Hence, a virtual array construction approach with specific platform motion design is proposed. Then, to conquer the gain-phase errors, a modified atomic norm is jointly considered to reconstruct the sample matrix. And a non-integer array interpolation algorithm is proposed to solve the non-integer node position problem caused by the limited platform control accuracy. Simulation based on several typical examples are given to illustrate the efficiency of the proposed method. IEEE