中文摘要：

提出了一种基于二维排序统计滤波器（OSF）的方法,滤除电离层后向散射探测中存在的随机冲激噪声与射频干扰.该方法利用电离层后向散射中随机冲激噪声在时间、空间和多普勒频域的不相关性和射频干扰在频域的不相关性,估计在一定时间、空间或频率窗口内回波强度的排序统计量作为滤波器的输出,可以分别滤除后向散射函数图和后向散射电离图中的冲激噪声和射频干扰.对于射频干扰和冲激噪声混合在一起的情况,通过调整滤波器滑动窗口大小和调整滤波器排序统计量输出,可以同时滤除这两种干扰,简化了处理步骤.实测数据处理结果表明,该方法能明显提高回波图质量.

英文摘要：

A technique based on 2D OSF （order statistics filter） was proposed to filter impulsive noise and radio frequency interference （RFI） in ionospheric backscatter sounding. This technique, in which the non-correlation of impulsive noise in time, space and Doppler frequency and non-correlation of RFI in frequency were used, estimated the order statistic of echo＇s amplitude in a fixed time, space or frequency window as the output of filter which can filter impulsive noise and RFI in raw backscatter function diagram and backscatter ionogram separately. In the case of impulsive noise and RFI mixing together, they can be simultaneously filtered by changing the sliding window size and outputting order statistic of filter, and filtering procedure was simplified. Processing result of measured data demonstrates this technique can markedly improve the quality of echo＇s diagram.