频谱校正技术在频率步进探地雷达中的应用研究

频率步进方法是探地雷达的工作体制之一。由于地下介质在各个频点对电磁波的衰减程度不同,导致频率步进探地雷达中回波信号频谱已经严重变形。文中基于恒Q模型推导了当考虑地下介质衰减特性时回波频谱的表达式,提出采用频谱校正技术对回波谱白化后进行匹配滤波。仿真结果表明,该技术大大提高了距离像的主旁瓣抑制比和分辨率,提高了地下目标检测能力。

A Study on Spectrum Correction Technique for Stepped-frequency Ground Penetrating Radar

Stepped-frequency ground penetrating radar (SFGPR) is a kind of the GPR. Due to different attenuation of electromagnetic wave transmitted in underground medium at every frequency point, the echo spectrum can not maintain rectangular. In this paper, based on constant Q model, the echo spectrum expression is deduced by taking into account the attenuation characteristic of the underground medium, and then a spectrum correction technique is proposed. The simulation results show that the high side-lobe suppression and resolution improvement can be achieved with the proposed technique, and so the capability of the underground target detection is significantly improved.