光学稀疏孔径系统复合阵列构造对系统成像的影响

Effect of Different Designs of the Multiple-Array Configuration on Imaging of Optical Sparse Aperture Systems

复合孔径阵列结构是通过复制子孔径来扩展阵列大小以得到甚高分辨率的一种有效手段。针对光学稀疏孔径系统的成像特征给出一种改进的信噪比(SNR)评价方法。在典型环形、典型Golay-6型和典型Y型阵列结构的基础上,研究了两种不同的复合孔径阵列构造方式。分析了6种复合阵列结构的调制传递函数,并以遥感影像为扩展物体进行光学成像实验,最后运用相关系数和改良后的信噪比对成像结果进行评价。结果表明,主阵列的结构决定了系统成像质量的好坏,子阵列构造方式只能在有限程度上改善图像质量。对不同类型的复合孔径主阵列,子阵列构造方式对成像质量的影响是不同的,并不具有一致规律。应针对主阵列结构的特征去选择其子阵列的构造方式.做到阵列优化。

Multiple-array configuration can achieve higher resolution by copying sub-aperture configuration to expand the size of the whole array. A modified signal noise ratio （SNR） is proposed to evaluate the imaging performance of optical sparse aperture systems. Based on the traditional array configuration, including the annulus, Golay-6 and the Tri-arm, two different ways for designing the multiple-array configuration are investigated. The imaging performances of six multiple-array configurations are analyzed according to their modulation transfer functions the evaluation criteria of the correlation coefficient and the modified SNR. The optical imaging experiments with the image of remotesensing as propagating object have been fulfilled. The results show that the main-array configuration plays the key role on the quality of the imaging, and the sub-array configuration can only improve the imaging performance to a certain degree. This means that the different design of the multiple-array configurations may lead to the different quality of the imaging. In order to optimize the array, the characteristics of the main-array should be considered to choose the way arranging its sub-array configuration.