抑制多径干扰的UWB SAR成像研究  

Research on UWB SAR Image Formation with Suppressing Multipath Ghosts

作　　者：王亮[1] 练有品[2] 周智敏[1] 宋千[1] 

机构地区：[1]国防科学技术大学电子科学与工程学院,长沙410073 [2]后勤工程学院后勤信息工程系,重庆400016

出　　处：《信号处理》2007年第3期403-406,共4页Journal of Signal Processing

摘　　要：传统的SAR成像算法不能消除多径传播的干扰,图像上出现虚假目标。本文建立了一种条带SAR模式的多径散射模型,通过分析得到多径产生的虚假目标的三个特征,即方向依赖、低分辨率和非理想聚焦。对低频大波束角SAR．虚假目标的方向性显著,据此本文提出一种能够抑制多径干扰的超宽带(UWB)SAR成像算法。仿真表明,本文算法可以使真假目标的峰值比提高13～18dB。Conventional SAR image formation algorithms can not remove the interference from multipath spreading events, so SAR images appear as ghosts. In this paper a multipath scattering model fit for stripmap SAR has been founded. By analyzing the model, we have obtained three characters of multipath ghosts, which are aspect dependence, lower resolution and non-ideal focusing. For low frequency band and large beamwidth SAR, the aspect dependence of ghosts is more remarkable. We hereby propose an ultra-wide band （UWB） SAR image formation algorithm with suppressing multipath ghosts. Simulations show that this algorithm may improve the peak value ratio between real and false targets about 13 - 18 dB.

关 键 词：多径传播 多径散射模型 UWB SAR成像 波数域支撑 多方向滤波 

分 类 号：TN958[电子电信—信号与信息处理]