针对天地波混合组网高频超视距海洋探测雷达系统,研究了阵列通道幅相误差的校准方法。通过相位偏置,将各站不同频率的回波分离开来;利用直达波校正原理,以及双层优选直达波幅相校准系数的方法,优选出最稳定的地波站直达波的幅相校准系数进行阵列幅相误差的校准,实现天波直达波到达角的估计。试验结果表明,该方法可以有效地避免杂波干扰引起的、不正确的校准值的影响,从而获得稳定的幅度和相位校准值,实现对阵列实时的校正。在此基础上,将校准后船只航迹的定位与AIS数据进行对比,结果吻合,表明了方法的可行性。
To calibrate the array errors with gain and phase uncertainty for hybrid networking HF-OTHR, a calibration approach for evaluating gain-phase errors is presented.The echoes of different frequency from every station are separated based on phase offset.Based on the direct wave calibration principle and the double preferred method for getting amplitude and phase calibration value,the array error can be calibrated with the most stable amplitude and phase calibration value and thus the sky direct wave DOA estimation can be achieved in real time.Experimental results show that it can avoid the effect of the error calibration value interference by the different clutters, getting a stable amplitude and phase calibration value to achieve real-time processing.The calibrated radar data and AIS on the target azimuthal angle and velocity are highly correlated which serve as a validation proof of the algorithm.