A Phase Error Estimation Method for Broad Beam High-Frequency Radar

High-frequency radar is an effective instrument for ocean state surveillance. However, phase response differences in antenna elements, cables and receivers cause distortions in beam pattern, resulting in the loss of azimuth resolution. In this letter, a novel method is presented to estimate phase errors in array received data using single-direction-of-arrival (DOA) first-order sea echoes as calibration sources. Eigenstructure decomposition of each signal is used to form a cost function. By minimizing the cost function, phase errors and DOAs are jointly estimated through an iterative procedure. For large phase errors situation, a conditional optimization is conducted to provide rough initial estimates for the iterative procedure. Simulation results reveal the effectiveness of proposed method. We apply this method to estimate the phase errors in the experiment data of multifrequency high-frequency radar. Experiment results validate its performance on DOA estimation.