【摘要】 基于矢量和(vector sum)原理,利用50∶50光纤耦合器、可变光延时线(VDL)、可变光衰减器(VOA)构建了微波光子移相器。以宽带光为载波有效地解决了合波处光波相位不同引起的微波信号不稳定的问题;利用马赫-曾德(M-Z)LiNbO3调制器在不同工作电压下的反相调制特性,设定调制器的不同偏置电压,同时配合调节两支路的光信号的功率比,采用两分支结构使10GHz的微波信号实现了350°的相位调谐。对微波信号的功率进行了测量,当两分支的光功率比为1∶1时,微波功率的衰减最大。更多还原

【Abstract】 A microwave photonic phase shifter is constructed and tested,which is based on the vector-sum principle and integrates 50∶50 couplers,variable optical delay line and variable optical attenuator.Broadband optical source is used as the carrier to effectively eliminate signal′s instability which is caused by different phase signals′ coupling.The 10 GHz microwave signal′s 350°phase-shift tuning range can be obtained by using the reversal phase characteristic of the Mach-Zehnder LiNbO3 intensity modulator and by tuning the optical power ratio of the carriers between two branches.According to measurements of microwave signal power,the maximal power attenuation appears when the power ratio reaches 1∶1.更多还原