基于再生锁模系统的低相噪微波源  

Low phase noise microwave source based on regeneratively mode-locked system

作　　者：苗旺[1] 于晋龙[1] 王菊[1] 孙斌[1] 孟天晖[1] 王文睿[1] 杨恩泽[1] 

机构地区：[1]天津大学电子信息工程学院,天津300072

出　　处：《光电子．激光》2012年第9期1702-1707,共6页Journal of Optoelectronics·Laser

基　　金：国家重点基础研究发展规划(2010CB327603;2012CB315704)资助项目

摘　　要：采用再生锁模光纤激光器作为高质量微波源的振荡级,产生了高质量的微波信号。为了保证振荡环路的稳定性,采用了锁相技术和腔长控制;采用"单模光纤(SMF)+法拉第旋光镜(FRM)"的结构代替了全保偏光纤,在腔内存在偏振扰动的情况下保证了系统稳定并降低了系统成本;在光生微波环路中加入了半导体光放大器(SOA),有效地提高了边模抑制比。最后,获得了的相位噪声为-98dBc/Hz(@10kHz)、线宽小于5Hz的20GHz微波信号。在10h的观测时间内,频率漂移小于2Hz,频率长期稳定性优于1×10-10。Optical pulse trains from mode-locked lasers carry low-jitter microwave signals. High-quality microwave signal could be obtained by using a band pass filter. A regeneratively-mode-locked fiber laser is used as an oscillation source to generate high-quality microwave signal. The phase-locked technology and cavity length control guarantee the stability of the system. The cost of the system is dramatically reduced by using the structure of ＂single-mode fiber＋Farady rotator mirror＂ instead of polarization-maintaining structure. A semiconductor optical amplifier （SOA） is introduced into the optical microwave loop, which improves the side-mode suppression ratio effectively. The generated 20 GHz microwave signal has great performance with phase noise of --98 dBc/Hz at 10 kHz and line-width less than 5 Hz. The frequency stability is better than 1×10-10 within 10 h observation.

关 键 词：微波源 再生锁模 腔长控制 半导体光放大器(SOA) 频率稳定性 

分 类 号：TN929.11[电子电信—通信与信息系统]