高速率电光调制器偏置电压自动控制技术

Research on Auto-control of Bias Voltage of High Speed EOM

采用电光检测的方法和误差分析的方式判断和识别电光调制晶体半波电压的漂移。利用PID控制算法实现高速率电光调制系统偏置电压高精度自动调节。最后对将研究的偏置电压自动控制系统应用于电光调制晶体,进行高速率调制实验。实验结果表明:采用偏置电压自动控制技术,改变了给电光调制晶体加载一个固定偏置电压的传统方式,使电光调制器偏置电压始终位于线性区的中点,以保证不失真调制,克服了电光调制器的半波电压受环境温度等多种因素的影响变化而电光调制晶体的半波电压发生漂移的问题。

An adopted auto control of bias voltage of Electro- optical modulator （EOM） is adopted to innovate the traditional manner that gives a constant voltage to the Electro - optical modulator. The use of auto - control of bias voltage makes EOM could have a good effect at different temperatures to acclimate all kinds of environment, in this way the bias voltage of EOM can always be at the midpoint of the zone of linearity, which can guarantee an adequate modulation without any distortion. The photoelectric detection and error analysis are adopted to judge and identify the shifting of the half voltage of EOM. Then PID control algorithm is used to realize a high precision auto - control. Finally, the EOM with the auto - control is applied to the EO modulation crystal to perform a high - speed modulation experiment.