基于光纤干涉仪的相位调制器半波电压的测量

基于相位调制干涉仪解调微波光链路的数学模型 ,提出了通过链路的S21增益峰值计算得到相位调制器半波电压的方案。 实验表明,此方法测得的相位调制器半波电压和厂家提供的数据相符合。把测得的相位调制 器半波电压应用在实际的光链路系统,增益仿真曲线和实验结果也相吻合 。在实验中,实现调制信号相位-幅度转换的光纤干涉仪由2个保偏 耦合器加特定跳线构成。实验结果表明,本文方案是一种结构简单、操作容易且具较高实 用价值的相位调制器半波电压测量方法。

Half-wave voltage measurement of phase modulator based on fiber interf erometer

Based on the mathematical model of the microwave photonic link with ph ase modulation and interferometer demodulation,we propose a method to measure the half-wave voltage of a phase modulator.The half-wave voltage is calculated through the S21of the peak gain of the small signal with a vector network analyzer (VNA).The ex periment results show that the data measured by this method has a good agreement with the data provided by the manufacturer.By a p plying the measured data of the phase modulator to our actual microwave photonic link system (the length difference between the two arms is 0.02m),the simulation curve successfully fits well the experimental data.In our experiment s,the tuning fiber interferometer,which is used to convert the phase-modulated signal into intensity-modulated signal,is construc ted with two 3dB polarization maintaining couplers and a special fiber jumper.Additionally,this method has simple stru cture,easy operation and high practical value for measuring the half-wave voltage of the phase modulator.