摘要
相干探测技术可以有效提高零差接收机的灵敏度。在空间激光通信系统中,零差接收机要求信号光和本振光的相位严格同步,光学锁相环是其中最常用的相位同步技术。介绍了对光学锁相环的理论模型,推导出相应的传递函数,同时指出了影响光学锁相环性能的主要参数,如环路噪声带宽、自然频率和阻尼比等。详述了各类光学锁相环的基本结构和特性,其中包括:平衡锁相环、Costas锁相环、同步位锁相环、振荡锁相环以及副载波锁相环,并对各类光学锁相环的性能进行了比较。总结了光学锁相环近年来的发展及应用,最后对该技术的前景进行了展望。
Coherent detection technology can improve the sensitivity of homodyne receiver effectively. In the system of space laser communication, homodyne receivers make the phases of a local oscillator （LO） signal and a signal wave synchronize, and the optical phase locked loop （OPLL） is the most efficacious technology. Firstly, by including the theoretical model of the optical phase locked loop, the corresponding transfer function is derived. Meanwhile the main parameters affecting the performance of the optical phase-locked loop are discussed, such as the loop noise bandwidth, the natural frequency, the damping factor of the loop. The basic structure and characteristic of each OPLL type are described including： balance OPLL, Costas OPLL, syncbit OPLL, dither OPLL and sub-carrier OPLL, and their properties are compared. Finally, the development and application of OPLLs are summarized, and the prospect of the OPLL technology is prospected.
出处
《激光与光电子学进展》
CSCD
北大核心
2015年第8期14-22,共9页
Laser & Optoelectronics Progress
基金
国家863计划(2012AA0042)
关键词
光通信
空间激光通信
相干探测
光学锁相环
副载波锁相环
optical communications
space laser communication
coherent detection
optical phase locked loop
sub-carrier optical phase locked loop
