中文摘要：

报道了一种新型的二阶晶体型偏振模色散（PMD）模拟器，其由3片可产生不同的一阶PMD差分群延迟（DGD）的晶体和1个法拉第旋转器组成，法拉第旋转器理论上可在180°内连续变化。该二阶PMD模拟器实验上能近似模拟从50到200ps^t的二阶PMD。给出了二阶PMD随偏置电压变化的曲线。实验表明，该器件输出的重复性好，响应时间小于1ms，实验值与理论值近似符合。

英文摘要：

A kind of crystal second order polarization mode dispersion （PMD） emulator is presented. This second order PMD emulator is composed of three differential group delay （DGD） crystal plates and a Faraday rotator whose rotator polarization angle varies with 180°. This emulator can emulate approximately the different second order PMD from 50 to 200 ps^t if we choose the different voltage on the faraday rotator. The experimental second order PMD curve is presented. It has been proved that the second order PMD emulator has good repeatability,the response time is less than 1 ms,and the experimental value fit the theory approximately well.