Computation-efficient 2-D DOA Estimation Algorithm with Array Motion Strategy

Two-dimensional (2-D) direction of arrival (DOA) estimation exploiting interlaced uniform planar array (IUPA) motion is discussed in this paper, and a Discrete Fourier Transform cascading Taylor Expansion (DFT-TE) algorithm is proposed. Specifically, the proposed IUPA structure possesses larger inter-element spacing than traditional uniform planar array (UPA), and it can mitigate the mutual coupling effectively. Simultaneously, the proposed IUPA structure is suitable for array motion. The synthetic IUPA generated by IUPA motion can offer more available array sensors and better DOA estimation performance than synthetic UPA and synthetic sparse uniform planar array (SUPA). Furthermore, considering the high computational complexity of 2-D DOA estimation, we propose the DFT-TE method. The DFT-TE method requires neither eigenvalue decomposition nor search operation. It gets the initial angles by employing the direct DFT method, and obtains the offset compensation for refined estimates by utilizing the Taylor Expansion method and total least squares (TLS) criterion. The proposed method has lower complexity and better estimation performance than the traditional 2-D DFT cascading search (DFT-S) method. Simulation results verify the effectiveness and advantages of the IUPA structure and DFT-TE method.