基于标量衍射的星间相干激光通信外差效率研究  

Research on Heterodyne Efficiency of Inter-satellite Coherent Laser Communication Based on Scalar Diffraction

作　　者：丁科[1,2] 李晓峰[3] 赵华[1,2] 

机构地区：[1]中国科学院光束控制重点实验室,成都610209 [2]中国科学院光电技术研究所,成都610209 [3]电子科技大学空天科学技术研究院,成都610054

出　　处：《半导体光电》2016年第1期95-99,103,共6页Semiconductor Optoelectronics

摘　　要：针对本振光为高斯分布,接收信号光经望远镜聚焦后为艾里分布的情况,首先对高斯和艾里函数用数值计算的方式得到两种光斑最大外差效率:当艾里斑直径和高斯光束束腰直径之比为1.719时,最大外差效率为81.45%;然后介绍了光的标量衍射和Zernike像差理论,分析了夫琅禾费衍射适用于相干聚焦光场的条件,计算了平面、高斯、艾里光场和Zernike像差的采样要求,对存在各种像差的光学系统的外差效率进行了仿真,分析了倾斜、离焦、像散、慧差、球差等基本像差及组合像差对外差效率的影响,结果表明:各种像差对外差效率的影响从低到高分别为像散、倾斜、离焦、慧差和球差;3dB外差效率损失对应相干系统的指标为跟踪误差优于1μrad(RMS),组合波像差优于0.1λ。研究结果对相干激光通信系统的链路损耗分配和光机系统的工程设计具有指导意义。First,assuming that the local oscillator wave obeys gaussian distribution and the received signal wave obeys airy distribution,numerical computation was adopted to acquire the maximum heterodyne efficiency.When the ration of airy spot diameter and gaussian spot waist diameter is 1.719,the maximum efficiency is 81.45%.Second,scalar diffraction and Zernike aberrations theory of optical field ere introduced and conditions that Franuhofer diffraction can be applied to coherent focus optical field.The sampling requirements for planar,gaussian and airy optical field were calculated.Then heterodyne efficiency simulation of optical system with various aberrations：tip/tilt,defocus,astigmatism,coma,spherical and their compositions were conducted.The results reveal that the order of aberrations＇ influence to the efficiency from low to high is astigmatism,tip/tilt,defocus,coma and spherical;3dB efficiency loss means that tracking error should be less than 1μrad（RMS）and wave-front error should be less than 0.1λfor a coherent laser communication system.Thus this study has some guidance significance to the link loss arrangement and engineering design of opto-mechanical system.

关 键 词：星间相干激光通信 标量衍射 泽尼克像差 本振光 外差效率 

分 类 号：TN929.1[电子电信—通信与信息系统]