提出并验证了一种借助于光纤环的选频特性实现辅助滤波的光电振荡器, 利用偏振分束器(PBS)和偏振合束器(PBC)构成的双环路结构抑制掉部分光电振荡器的边模, 同时借助于光纤环的光学梳状频率特性, 对振荡器环路中的光信号模式再次进行选择, 既起到边模抑制的作用, 又提高了光电振荡器谐振腔的Q值。仿真结果表明: 采用光纤环辅助滤波有利于光电振荡器的边摸抑制和单模输出, 在保证光电振荡器输出低相位噪声和高频谱纯度微波信号的情况下, 边模抑制比超过160dB, 模式间隔达到370MHz, 降低了对电域带通滤波器的性能要求, 是一种新的光电振荡器设计方案。

An optoelectronic oscillator with assistant filtering by means of the frequency selective characteristic of optical fiber ring is proposed and verified. The dual-loop structure composed of a polarization beam splitter (PBS) and a polarization beam combiner (PBC) is used to suppress the edge of the optoelectronic oscillator. Furthermore, the mode of the optical signal in the oscillator loop is selected again by means of the optical comb frequency characteristic of optical fiber ring, which plays the role of side mode suppression and improves the quality factor of the resonator. The side-mode rejection ratio is over 160dB and the mode interval is up to 370MHz in the case of ensuring low phase noise and high spectral purity of the microwave signal by the optical oscillator, which reduces the performance requirements of the band-pass filter, and is a new design scheme of the optoelectronic oscillator.