同时校正电离层幅度和相位污染的MLE方法

Maximum likelihood estimation of correcting ionospheric amplitude and phase contamination simultaneously

针对天波超视距雷达回波中电离层幅度污染和相位污染同时存在的情况,提出采用标校信号自适应提取与最大似然估计(MLE)相结合的校正方法.该方法通过展宽布拉格峰的功率拐点自适应确定提取标校信号的滤波器带宽,基于MLE对相邻多个距离单元的回波数据进行电离层幅度污染和相位污染的同时估计.采用实测数据添加污染的方式进行实验验证,并与相位梯度法进行了比较.理论分析和实测数据处理结果表明:该方法能够准确确定滤波器带宽,可同时校正电离层幅度和相位污染.

To deal with the amplitude contamination and phase contaminations in the echo of over the horizon radar, the joint calibration signal adaptive extraction and maximum likelihood estimation （MLE） method was presented. In this approach, the bandwidth of filter used to extract calibration signals was determined through turning point of the spreading Bragg peak power. Then ionosphere amplitude and phase perturbation were estimated by MLE algorithm. This algorithm adopted real data added contamination to verify the experiments. Theoretical analysis and real data processing indicate that by combination with MLE algorithm, the new approach can determine the filter bandwidth accu- rately and eliminate both amplitude and phase contamination.