Abstract:

To solve the problem that the property of spatial spectrum estimation algorithms is sensitive to array channel amplitude-phase mismatch, a real-time calibration method based on self-checking signal is proposed according to the characteristic of actual receiving channel. The whole channel calibration is divided into two parts: the precalibration of passive devices between antennas and receiving channels and the realtime calibration of receiving channels. At first, it can get the pre-calibration matrix by setting a signal which has direction of arrival of 0°. Then, it can realize realtime calibration using self-checking signal during the process of  direction finding. Simulation results of Matlab prove that the proposed real-time calibration method can dynamically calibrate the channel amplitudephase mismatch and it is helpful to prompt the solve ability of MUSIC algorithm. The experimental result in actual direction finding system show that it can calibrate amplitude-phase mismatch real-timely and get higher direction finding precision.