光学频率梳空间应用及研究进展

Spatial application and research progress of optical frequency combs

光学频率梳具有时域超短脉冲和频域宽光谱、窄线宽、等间隔相干频率梳齿的优良特性,并兼具联系光学频率与微波频率的能力,在空间应用中具有广阔前景,目前已在多个领域取得突破性进展。文章梳理了光频梳产生方法的技术现状,分析了光频梳在空间时频基准、空间时频传递、精密测量以及大容量相干光通信等空间应用领域的研究进展。其中,光频梳在空间时频基准中为高精度时间和频率标准的建立提供了重要支持;在空间时频传递中,光频梳有助于实现精确的时间和频率同步,为星间、星地和洲际尺度的空间应用提供高精度时间频率对比分发;在精密测量中,光频梳可提供宽工作频率范围内的高精度快速测量,在精密测绘、光学定位、目标跟踪和遥感等领域有着广泛的应用潜力;而在大容量相干光通信方面,光频梳具有多载波强相干的突出优势,可用于实现高速、稳定的光通信系统,满足大容量数据传输的需求。随着光频梳产生技术、调控手段的进一步成熟,光频梳在空间应用的各个领域将发挥更重要的作用。但是面向工程化应用,仍需解决环境适应性、系统集成、稳定性和可靠性等方面的难题。

Optical frequency combs(OFCs)are powerful instruments in space applications with excellent characteristics of ultra-short pulse in the time domain,wide spectrum in the frequency domain and millions of mutually coherent,perfectly spaced comb modes which provide a link from the optical frequency to the radio-frequency and consequently enable unprecedentedly precise,absolute measurements of optical frequencies.Great breakthrough progresses have been made in many application fields over years.In this paper,the technical status of OFCs’generation scheme is summarized,and the research progresses in space application fields such as time-frequency reference,time-frequency transmission,precision measurement and high-capacity coherent optical communication are described and analyzed.In the field of time-frequency reference,the OFCs provide important support for the establishment of high-precision time and frequency standards.In the time-frequency transmission field,the OFCs help achieve precise time and frequency synchronization,providing high-precision time-frequency comparison and distribution for various systems at global,terrestrial and intercontinental scales.In the precision measurement field,the OFCs offer high-precision rapid measurement over a wide range of working frequencies,showing broad application potential in precise mapping,optical positioning,target tracking,and remote sensing.In the field of high-capacity coherent optical communication,the OFCs exhibit outstanding advantages in strong coherence of multi-carrier,enabling the realization of high-speed and stable optical communication systems to meet the demands of high-capacity data transmission.With further advancement in the generation and control techniques,the OFCs will play a more significant role in space applications.However,for practical engineering applications,it is still necessary to address challenges related to environmental adaptability,system integration,stability and reliability,etc.