基于半导体激光器注入锁定载波恢复技术的星间相干激光通信系统  

Intersatellite Coherent Laser Communication System Based on Semiconductor Laser Injection⁃locked Carrier Recovery Technique

作　　者：刘天睿 任伟杰 章郑豪 孙建锋 苏庆帅 魏芳[3,4] 李权 杨康文 蔡海文 Liu Tianrui;Ren Weijie;Zhang Zhenghao;Sun Jianfeng;Su Qingshuai;Wei Fang;Li Quan;Yang Kangwen;Cai Haiwen(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Shanghai Satellite Internet Research Institute Co.,Ltd.,Shanghai 201204;Wangzhijiang Innovation Center for Laser,Aerospace Laser Technology and System Department,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;Zhangjiang Laboratory,Shanghai 201210)

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093 [2]上海卫星互联网研究院有限公司,上海201204 [3]中国科学院上海光学精密机械研究所空天激光技术与系统部王之江创新中心,上海201800 [4]张江实验室,上海201210

出　　处：《中国激光》2024年第23期72-81,共10页Chinese Journal of Lasers

基　　金：国家自然科学基金(62275253,U23A20379);上海市自然科学基金(21ZR1472100);中国科学院战略性先导科技专项(B类)(XDB43030400)。

摘　　要：空间相干激光通信技术是当前卫星互联网远距离高速通信的主要途径,针对当前零差相干通信体制中光学锁相环载波恢复技术存在的锁定范围小、系统复杂以及对激光器线宽和频率调谐带宽要求高的问题,研究了基于半导体激光器注入锁定技术的相干接收端载波恢复方法,并利用数字解调技术实现了信号的接收。发射端采用曼彻斯特码型二进制相移键控(BPSK)调制技术有效保留了发射光信号中的载波分量,在接收端通过半导体激光器注入锁定技术对调制光中的载波分量进行过滤和放大,并将其作为本振光与调制信号进行混频探测,利用数字解调算法实现了通信速率为5 Gbit/s的BPSK相干信号的解调,同时分析了注入功率、调制速率和调制深度的改变对载波恢复效果的影响。该方案可有效降低空间相干激光通信对本振光的性能及接收端采样速率的要求,极大简化了空间相干通信系统的复杂度。Objective In a space-integrated ground information network,high-speed laser communication is a key technology for high-speed intersatellite data transmission.Owing to its high sensitivity and strong anti-interference capabilities,coherent laser communication has become an ideal choice for long-distance inter-satellite communication.However,traditional analog coherent demodulation technology requires a complex optical analog lock-in loop(OPLL)control system and places high demands on the performance of the local oscillator laser,which increases the complexity and cost of the system.To address these issues,a new carrier recovery method is explored in this study and combined with digital coherent demodulation technology to reduce the system complexity.Methods A carrier recovery method for a coherent receiver based on semiconductor laser injection locking technology is investigated,and digital demodulation technology is used to realize signal reception.Manchester-coded binary phase-shift keying(BPSK)modulation technology is used at the transmitter to effectively retain the carrier component in the transmitted optical signal.The carrier component in the modulated light is filtered and amplified via semiconductor laser injection locking technology at the receiver,which is frequency-shifted by 160 MHz using an acousto-optic modulator before entering the 90°optical hybrid.The frequency shift reduces the effect of low-frequency beat noise on the system.A balanced photodetector with alternating current coupling is used to detect the mixed signal,and an oscilloscope is employed to collect the signal.The collected signal is processed offline to obtain a demodulated encoded signal.Results and Discussions Experiments are conducted on carrier recovery based on injection-locking technology at the receiver end.The impacts of different modulation depths,signal rates,and injection ratios on the performance of the local oscillator light after injection locking are analyzed.A decrease in the modulation rate and increases in the modu

关 键 词：星间相干激光通信技术 光学锁相环 注入锁定 载波恢复技术 

分 类 号：O436[机械工程—光学工程]