基于最优子阵划分ESPRIT的任意线阵高精度DOA估计算法

为了提高任意阵列的波达方向（direction of arrival, DOA）估计性能，从对子阵阵元选取进行优化的角度出发，提出了基于最优子阵划分旋转不变信号参数估计技术(estimation of signal parameters via rotational invariance techniques, ESPRIT)的任意线阵高精度DOA估计算法. 该算法首先利用虚拟插值阵列ESPRIT（virtual interpolated array ESPRIT, VIA-ESPRIT）得到精度较低的DOA粗估计. 其次以DOA粗估计为参考对任意阵列进行相位补偿，使其具备旋转不变性. 然后根据ESPRIT算法原理对构建旋转不变方程的子阵划分进行优化，并通过优化后子阵间的旋转不变性得到高精度的DOA估计. 此外，本文还分析了子阵划分对算法估计性能的影响，给出了子阵最优选取的近似计算方法. 计算机仿真结果验证了所提算法的有效性，并表明其性能逼近克拉美·罗界（Cramer-Rao bound, CRB）.

Optimal subarray partition ESPRIT-based DOA estimation algorithm with high accuracy for arbitrary linear array

In order to improve the accuracy of direction of arrival (DOA) estimation with arbitrary array, from point of view of optimizing the subarray elements, an optimal subarray partition estimation of signal parameters via rotational invariance technique (ESPRIT) based DOA estimation algorithm with high accuracy for arbitrary linear array is proposed. Firstly, virtual interpolated array estimation of signal parameters via rotational invariance technique (VIA-ESPRIT) is utilized to obtain the coarse estimation. Secondly, to acquire the rotation invariant feature, the coarse estimation serves as the reference to carry out the phase compensation on arbitrary array. The subarrays are optimally partitioned to construct the invariance equation are according to the ESPRIT principle. Then the rotational invariance between the optimized subarrays is utilized to obtain a high accuracy DOA estimation. Furthermore, the effect of subarray partition on the performance of DOA estimation is analyzed, and an approximate calculating method of optimal subarray partition. Computer simulation results show the effectiveness of the proposed algorithm, and its high performance is close to the Cramer-Rao bound (CRB).