步进频率探地雷达应用中,射频干扰严重影响合成孔径成像效果和目标检测性能。该文使用随机相位编码技术在不影响目标回波的情况下,可将所有射频干扰变为零均值随机信号,进而用经典的均值滤波方法进行干扰抑制。分析表明使用随机相位编码技术使步进频率探地雷达具有噪声雷达的射频干扰抑制能力,同时保留了步进频率良好的主副瓣比性能和利用FFT进行快速信号处理的优点。蒙特卡洛仿真结果验证了本文分析的正确性和随机相位编码对步进频率探地雷达射频干扰抑制的有效性。
The Radio Frequency Interference (RFI) makes the most performance degradation for the Synthetic Aperture Imaging (SAI) and the object detection of Stepped-Frequency Ground Penetrating Radar (SFGPR). This paper proposes a random phase-coded method to transform RFI into zero-mean random signal without effect on the object's echo. Then the RFI can be suppressed easily by a classical average filter. Analysis indicates that the proposed method makes the SFGPR have the same anti-RFI performance as that of noise radar. It keeps the low sidelobe property of SFGPR and can be realized by FFT. Monte Carlo simulation conforms to the theoretic analysis and demonstrates that the proposed method is effective