光学合成孔径一维旋转阵列多帧成像优化方法  

Multi-frame imaging optimization of optical synthetic aperture 1D rotation array

作　　者：魏小峰[1] 耿则勋[1,2] 徐志军[1] 卢兰鑫 

机构地区：[1]解放军信息工程大学地理空间信息学院,河南郑州450001 [2]许昌学院,河南许昌461000

出　　处：《光电子．激光》2015年第4期772-779,共8页Journal of Optoelectronics·Laser

基　　金：国家新技术研究发展"863"计划(2012AA7801014)资助项目

摘　　要：为提高一维合成孔径阵列的成像分辨率,研究利用旋转基线的方式实现含相位误差情况下的一维阵列多帧成像与复原。首先比较不同子孔径数及排列方式的优劣,确定合适的阵列结构;然后通过旋转基线进行多帧成像,实现频谱在各方向上的覆盖;利用多帧维纳滤波进行复原,以相关系数为评价准则,并结合成像性能与效率在3种备选方案中确定理想的旋转方式;最后通过增加旋转次数,实现频谱的重复覆盖,以消除考虑相位误差对成像质量的影响。实验表明,以60°旋转5次成像时,一维三孔径阵列的活塞误差容限为0.07,倾斜误差容限为40μrad。本文提出的一维旋转阵列多帧成像方法可以在消除一定相位误差影响的同时实现高清晰复原,具有较强的实用价值。1D synthetic aperture array has obvious advantages on imaging efficiency while the unequal dis- tribution of its intensity reduces the resolution. Hence this research is focused on the multi-frame ima- ging and restoration by rotating the baseline of 1D optical synthetic aperture system with phase errors. Firstly,lD arrays with various sub-aperture numbers or arrangements are compared thoroughly and the proper array structure is determined then multi-frame images are obtained by rotating the baseline which covers most of the frequency domain,and then multi-frame Wiener filter algorithm is proposed and ap- plied to restore the collected images with various frequency spectrums. Furthermore, the restoration quality is assessed by correlation coefficient. Taking both performance and efficiency into account, the i- deal rotation method was determined among three given candidates. Finally, by increasing the rotation times, the spectrum is covered repeatedly so as to eliminate the influence of phase errors. While imaging by rotating 5 times with 60°,the piston and tip/tilt error tolerances of 1D three-aperture array are 0.07 and 40, separately. The proposed multi-frame imaging method of 1D rotation array can realize the high resolution restoration as well as eliminating the influence of phase errors.

关 键 词：一维阵列 光学合成孔径 旋转基线 多帧复原 相位误差 

分 类 号：O436[机械工程—光学工程]