强的墙体直达波严重干扰了穿墙成像雷达的目标信号,而采用稀疏阵列天线的穿墙雷达,由于通道数少使得基于单次快拍数据分离目标和干扰信号难度更大。该文根据实际通道每次收发获取的距离像存在微弱起伏的现象,提出一种采用单通道多次快拍数据建立观察矩阵,并使用独立分量分析分离直达波与目标信号的方法。仿真及实测数据处理结果表明,在低信杂比(-30 dB)的条件下,该方法仍可有效分离目标和干扰成分,达到较好的直达波抑制效果。
For Through-the-Wall Imaging Radar (TWIR), wall clutter is critical for detecting target signals behind a wall. For a system with a sparse antenna array, the lack of observation channels makes it more difficult to separate the target signals and wall clutter. On the basis of fluctuation of the range profile in real transmit/receive channels, this paper proposes to use Independent Component Analysis (ICA) on multiple down-range observations of each transmit/receive channel to remove the wall clutter. The simulation and experimental results show that the proposed method effectively separate target and clutter components, even though the signal-to-clutter ratio is only -30 dB.