Calibrating Nonuniform Linear Arrays With Model Errors Using a Source at Unknown Location
Chaolin Yang, Zhi Zheng, Wen-Qin Wang · IEEE Communications Letters · 2020
The effect of gain and phase error between array elements can seriously degrade the performance of array signal processing, and hence, gain-phase error calibration has attracted much interests. In this letter, we focus on the problem of calibrating the gain and phase errors of nonuniform linear arrays (NLAs) with an auxiliary source. Firstly, the main diagonal entries of the array covariance matrix is utilized to estimate the gain errors. Subsequently, with the initial estimates of the gain errors, the NLA is iteratively calibrated by estimating successively the direction-of-arrival (DOA) and the gain-phase errors. Unlike the existing methods, the proposed algorithm achieves DOA estimation in the coarray domain, partially reducing the impacts of the array model errors. Numerical results demonstrate the effectiveness of the proposed approach.