双基地穿墙成像合成孔径雷达具有广阔的应用前景。建立了发射站工作在正侧视条带模式,接收站固定构形的双基地SAR信号穿透墙体的数学模型,研究解决了双基地SAR穿墙成像中电磁波的折射和传播路径等问题。分析了与空气介质条件下相比的回波延时,孔径变化和分辨率特征,推导了双基地SAR穿墙后向投影(Back Projection,BP)成像算法,对墙体的折射和延时作用进行补偿。给出了墙后目标的非聚焦和聚焦成像结果,仿真结果验证了理论分析和算法的正确性与有效性。
Bistatic through-wall imaging SAR has a promising future.The model of bistatic SAR through-wall imaging is established,in which transmitter is working in side-looking strip mode together with a stationary receiver.The propagation path of signal due to refraction is figured out.Characteristics of echo delay,synthetic aperture variation and resolution are compared and analysed with those under the condition of atmospheric medium.The back projection algorithm of bistatic through-wall imaging SAR is deduced to compensate the refraction and delay effect of wall.The defocused and focused images of targets behind wall are simulated.Validity of the theoretical analysis and the algorithm is verified by simulation results.