基于光纤光栅辅助耦合的WDM下话路研究

Wavelength-Division Demultiplexer Based on FBG Coupler

利用光纤光栅的反射特性和光纤耦合器的耦合特性,研究基于光纤光栅辅助耦合波分复用(WDM)下话路器。满足国际电信联盟(ITU-T)建议波长的WDM光信号从耦合器输入端口进入,其中与光栅中心反射波长一致的激光信号从耦合器的下话路端口输出,而其他波长的激光信号从耦合器输出端口输出,实现特定波长信号的下话路。选择中心波长分别为1554.248 nm,1555.859 nm,消光比为57 dB的两路光信号进行试验,光纤光栅的中心反射波长为1555.86 nm,实验结果表明,上述两路光信号分别从不对称光纤耦合器的输出端口和下话路端口输出,且在下话路端口输出光信号的消光比为48 dB。

By using the reflectivity property of fiber Bragg grating （FBG） and the coupling property of coupler, a wavelength-division demultiplexer based on FBG coupler is designed. The WDM signals are injected from the input port of the coupler, and the signal which has the same wavelength as that of FBG will be output from the demultiplex port of the coupler, and the other signals will be output from the output port of the coupler, thus the demultiplex is implemented. The experiment of two signals with different wavelengths of 1554. 248 nm and 1555. 859 nm are implemented, and the extinction ration of each is 57 dB, and the center wavelength of FBG is 1555.86 nm. The results show that the signal output from the demultiplex port with extinction ration of 48 dB.