Array errors active calibration algorithm based on instrumental sensors

Abstract

The array mutual coupling, gain-phase errors and sensor position errors would significantly degrade the performance of high-resolution direction of arrival (DOA) estimation algorithms. Aiming at the combined influences of the above three array errors, a kind of active calibration algorithm is presented with the help of instrumental sensors in this paper. Firstly, the integrated effects of the three array errors are shown to be equivalent to angularly dependent gain-phase errors. Then, a non-linear least square (LS) optimization model for the three array errors is established through an auto-calibration algorithm using auxiliary sensors, and the corresponding resolving algorithms of the LS optimization problem are given according to the different models of array errors matrix. Next, the parameter estimation uniqueness of the proposed algorithms is analyzed in detail and an improvement strategy is given. Finally, the effectiveness of the novel algorithm is validated by simulations.