基于RD谱轮廓线的高频地波雷达二阶谱提取

The Second Order Spectrum Extraction From High Frequency Ground Radar Sea Echoes Based on the Outline of the RD Spectrum

雷达回波谱中的噪声和目标回波会对二阶谱的提取造成困难。基于地波雷达海面回波谱特性,提出了一种采用距离-多普勒谱(RD谱)轮廓线结合一阶和二阶谱特点的二阶谱提取方法。此方法可以通过计算机自动实现对二阶谱的提取,有利于大批数据的分析和工程化系统的实时处理。利用该方法对典型实测雷达回波数据进行了处理和分析。结果表明,RD谱轮廓线能够反映一阶谱和二阶谱的特征,并且不易受噪声和目标的影响;从RD谱轮廓线获得的二阶谱分界点,可以为一维多普勒回波谱中的二阶谱提取提供参考,能够较好地避免由于目标和噪声的影响而导致的二阶谱边界误判问题,准确地分离二阶谱。

The noise and the target echo signal existing in the Hgh Frequency Surface Wave Radar （HFSWR） echoes can cause trouble for extraction of second order spectrum. According to the characters of the HFSWR echoes, a method exploring the outline information of the Range Doppler （RD） spectrum in combination with the features of the first and second spectrum is presented in this paper. The method can be implemented to extract the second order spectrum by computer, which is conducive to amounts of data a nalysis and the real time processing data by engineering system. This method is applied to the typical radar data processing and analysis, and the results show that the features of the first and second spectrum can be reflected by the outline of RD spectrum which is not influenced by noise and target echo. Based on the sec ond spectrum boundary points obtained from the outline, the issue of boundary error judgment due to the influence of the noise and the target echo can be avoided, when the second spectrurn is extracted from the one dimensional Doppler spectrum echo.