为了获得不同间隔双波长信号输出, 提出一种基于受激布里渊效应产生双波长激光的实验装置, 利用不同间隔双波长输出信号进行拍频实验可获得可调的微波信号输出; 利用一段10 km长普通单模光纤(SMF)作为布里渊增益介质, 一个线宽为5 kHz分布反馈激光器(DFB)作为布里渊抽运源, 一段未泵浦的保偏掺铒光纤用作饱和吸收体抑制边模, 通过改变未泵浦保偏掺铒光纤的长度, 可获得不同间隔输出的双波长光纤激光器, 实验获得波长间隔为0.170 nm和0.085 nm的激光信号输出, 分别对应20 GHz和10 GHz的微波信号。

In order to obtain dual-wavelength output with different intervals, an equipment to generate dual- wavelength laser based on simulated Brillouin effect was put up. The tunable microwave signal was got through beat frequency experiment for the different intervals dual-wavelength output signal. A segment of 10 km single-mode fiber (SMF) was used as the Brillouin gain medium and a 5 kHz distributed feedback (DFB) semiconductor laser was used as the Brillouin pump (BP). An un-pumped polarization maintaining erbium-doped fiber (PM-EDF) was used as the saturable absorber to suppress unwanted side-modes. Different-interval dual-wavelength output was obtained by changing the length of un-pumped PM-EDF. In the experiment, dual-wavelength outputs with 0.170 nm and 0.085 nm spacing were achieved, corresponding to 20 GHZ and 10 GHZ microwave signals.