近程毫米波合成孔径辐射计成像系统分析

Analysis on Near Range Millimeter Wave Synthetic Aperture Radiometer Imaging System

设计了一套用于近程被动成像的毫米波合成孔径辐射计(MMW-SAR)系统,由在水平和垂直方向上扫描的一对辐射计以及后端的信号处理系统组成,可对几米内的目标成像。文中给出了成像系统的总体结构和成像算法;并提出近程成像的特点是需要相位补偿;并首次在直角坐标系下推导了合成孔径成像公式,简化了表达式和相位补偿运算;另外在计算相关函数时提出采用多相滤波算法,有效地克制了相关函数虚部的波动,提高了成像质量和系统效率。

A near sensing millimeter wave synthetic aperture radiometer （MMW-SAR） passive imaging system was developed, which is composed of a signal processing system and two radiometers scanning along horizontal and vertical direction, to take images of the target within several meters. Configuration and imaging algorithms of the imaging system were given in detail; it was proposed that the chief characteristic of near range imaging is phase compensation {actor in imaging formula; the synthetic aperture imaging formula in the Cartesian coordinate system was deduced for the first time, to simplify arithmetic of the expression and the phase compensation; the multiphase filtering algorithm was proposed in calculating the correlation function, to restrain the fluctuation of imaginary part of the correlation function, and improves imaging quality and system efficiency.