基于全息聚合物液晶光栅的动态增益均衡器的设计与模拟

Design and Simulation of Dynamic Gain Equalizer Based on Holographic Polymer Dispersed Liquid Crystal Volume Grating

介绍了聚合物分散液晶（PDLC）材料及体全息光栅的特性，提出了基于全息聚合物液晶（H—PDLC）电控光栅多极串联式动态增益均衡器的设计。根据光栅的衍射特性计算公式，对全息聚合物液晶光栅在中心波长为1550nm的波长选择特性进行模拟，并且进一步利用遗传算法模拟实现全息聚合物液晶动态光强增益均衡器的功能。计算模拟表明，选择合适的全息聚合物液晶光栅参量，能够使光栅在1550nm为中心波长的衍射谱线半宽度达到10nm。同时，采用基于全息聚合物液晶的动态光强增益均衡器，能够使掺饵光纤放大器在1530～1560nm内，其自发辐射谱的不平坦度从3．3dB降到0．1dBp-p（峰-峰值）。

The characteristics of polymer dispersed liquid crystal （PDLC） and holographic polymer dispersed liquid crystal （H-PDLC） volume grating are introduced. Based on the novel H-PDLC volume gratings, series-connecting dynamic gain equalizer design is provided. Furthermore, simulations are made about wavelength selectivity of HPDLC grating at 1550 nm and the function of H-PDLC dynamic gain equalizer. The calculation results show that when suitable grating parameters of H-PDLC are selected, half spectral width of grating is about 10 nm at central wavelength of 1550 nm. And the fluctuation of spontaneous emission spectra of erbium-doped fiber amplifier （EDFA） can decrease from 3.3 dB to 0.1 dB within 1530 nm to 1560 nm based on H-PDLC dynamic gain equalizer.