基于数字化相位补偿的激光水下频率传输  

Laser Underwater Frequency Transmission Based on Digital Phase Compensation

作　　者：韩丽莉 杨飞[1] 曹康 臧华国[1] 陈卫标[1] Han Lili;Yang Fei;Cao Kang;Zang Huaguo;Chen Weibiao(Key Laboratory of Space Laser Communication and Detection Technology,Aerospace Laser Technology and System Department,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;School of Physical Science and Technology,ShanghaiTech University,Shanghai 201210,China)

机构地区：[1]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中科院空间激光信息传输与探测技术重点实验室,上海201800 [2]上海科技大学物质科学与技术学院,上海201210

出　　处：《中国激光》2024年第22期162-168,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(12293033);中国科学院先导项目(XDB43030400);中国科学院青年创新促进会(YIPA2019251)。

摘　　要：水下频率传输与同步是海洋时空基准的关键技术基础,随着海底观测网等科技发展,传输精度等性能指标的要求越来越高。提出基于数字化相位补偿的高精度蓝绿激光的水下频率传输方法,利用蓝绿激光作为载波,采用数字化相位补偿技术,优化频率传输噪声、补偿带宽。基于520 nm绿光二极管进行实验验证,实现400 MHz频率信号在水下8 m链路上的双向稳定传输。实验结果表明,该技术的相位补偿带宽达到1 kHz,频率信号经过相位补偿后的频率传输稳定度在1 s处为7.9×10^(-14),在1000 s处为2.1×10^(-16)。证明该数字化补偿技术在水下蓝绿激光频率传输中的可行性,同时数字化技术还便于系统集成和小型化,在水下导航定位授时、水下时空网络建设等领域中有着重要的应用前景。Objective With the gradual exploration and development of ocean resources,human efforts towards dynamic sensing,precise detection,information network construction,and data collection in marine environments will continue to expand,leading to a deeper understanding of the ocean.The marine spatiotemporal benchmark network is a common infrastructure for marine positioning and navigation systems,ocean environmental monitoring networks,and the Internet.Among these,underwater frequency transmission and synchronization constitute a crucial technological foundation for oceanic spatiotemporal benchmarks.With the advancements in science and technology,such as underwater observation networks,there is an increasing demand for higher precision in frequency transmission performance indicators.Methods This study proposes a high-precision underwater frequency transmission method for the blue-green laser based on digital phase compensation.Referring to the approach used in ground-based fiber optics,a dual-way time-frequency transmission is employed to enhance stability.Compared with the one-way transmission,the dual-way scheme allows for the signal returned from the remote end to be compared against the local reference signal,thereby improving the precision of the noise measurement.Using the blue-green laser as the carrier and digital phase compensation to enhance the frequency transmission noise compensation bandwidth,the method is experimentally verified with a 520 nm green laser diode,achieving bidirectional stable transmission of a 400 MHz frequency signal over an 8 m underwater link.A digital phase compensation system that included error signal acquisition,proportional-integralderivative(PID) control,and digital phase shifting was established.Digital phase-shifting is applied to pre-compensate for additional phase fluctuations in the process of underwater frequency transmission to maintain the stability of the frequency of the underwater link.The experimental device for the underwater laser frequency transmission based on dig

关 键 词：光通信 高精度频率传输 数字化相位补偿 蓝绿激光 水下时空基准 

分 类 号：Q436[生物学—生理学]