中文摘要：

基于一种新型的电离层斜向返回探测系统，针对其不同于传统高频天波雷达的回波谱特点，提出了一种回波预处理方法．该方法通过最大值搜索法进行地波定标、平均插值法消除盲区和统计阈值法消除射频干扰，然后将探测得到的数据进行处理．结果表明，处理后的回波谱真实有效地反映了电离层状态，射频干扰得到了有效抑制（衰减了6～7dB）．

英文摘要：

We can get realtime information of the distant ionosphere by using the Ionospheric Oblique Backscattering System, which adopts discontinuous wave mechanism. Having analyzed the characteristics of the ionospheric echo Doppler spectra, the signal preprocessing is developed in this paper, which aims at improving the Doppler spectra. The results indicate that the preprocessing not only makes the system has higher ability of target detection but also suppresses the radio frequency interference by 6～7 dB.