【摘要】 该文将非即时u-v覆盖的综合孔径射电天文观测中的CLEAN算法应用到即时u-v覆盖的机载二维被动毫米波综合孔径成像中,避免因空间频率覆盖的不完整而产生对图像质量的影响,以达到消除高旁瓣对图像产生的负面影响。该文主要分析了CLEAN算法中具体处理时的“清洁”脉冲类型、脉冲半峰值宽度和迭代比例因子γ对处理后的图像的影响。研究结果表明:当清洁脉冲半宽度峰值等于系统脉冲响应图的半峰值宽度时、迭代比例因子γ为1/256时以及清洁脉冲类型为高斯脉冲时有利于改善图像的质量,该结论对实际的机载被动毫米波综合孔径成像的工程研究具有重要的参考价值。更多还原

【Abstract】 The CLEAN algorithm is introduced from non-instant u-v coverage aperture synthesis in radio astronomy to instant situation in 2-D airborne mm-wave imaging, to remove the bad influences of the undersampled u-v plane coverage to image quality so as to eliminate the negative impacts on the image caused by high side slobs. In this paper, the effects of the kind of “clean” impulse, the relevant FWHM and the scale coefficient γ to the quality of the modified image is mainly studied, and a conclusion is that: a Gauss “clean” impulse, a relevant FWHM equal to the FWHM of system response and the scale coefficient γ about 1/256 is favorable to improve the modified image. This conclusion is valuable to the real airborne mm-wave aperture synthesis imaging project.更多还原