一种倍频因子及输出相位连续可调的微波光子移相系统

提出一种倍频因子连续可调,且相位连续变化的微波光子移相系统.系统主要由两个集成双偏振双平行马赫增德尔调制器组成,在不使用光滤波器的情况下,调节双平行马赫曾德尔调制器及相位调制器的射频驱动和直流偏置电压,生成二倍频,三倍频,…,六倍频微波信号,同时实现输出微波信号相位0~360°连续可调.仿真结果表明,当射频信号频率为10GHz时,可分别产生频率为20、30、40、50、60GHz的微波信号.调节相位调制器的直流偏置电压与半波电压比值从-1到1变化时,对应微波信号的相位从-180°到180°变化.此外,分析了调制器消光比对输出微波信号光载波抑制比和电杂散抑制比的影响,以及90°电桥相位平衡对微波信号相位漂移和幅度波动的影响.

A Photonic Microwave Phase-shifting System with Continuously Tunable Phase Shift and Frequency Multiplication Factor

A photonic microwave phase-shifting system with continuously tunable phase shift and the frequency multiplication factor is proposed.Without optical filters,the scheme is mainly consists of two integrated dual-polarization dual-parallel Mach-Zehnder modulators.By adjusting voltages of the radio frequency driving signal and direct current bias signal on the dual-parallel Mach-Zehnder modulators and phase modulator,frequency-doubling or frequency-tripling,...,frequency-sextupling microwave signal can be generated,with 0°to 360°continuously tunable phase shift.The simulation results show that,when the radio frequency signal frequency is 10 GHz,the output microwave signals with the frequency 20,30,40,50,60 GHz can be obtained respectively.The ratio of direct current bias voltage and half-wave voltage of the phase modulator is set to vary from 0 to 1,corresponding to phase shift of microwave signal vary from-180°to 180°.In addition,the effects of the extinction ratio of the modulators on the optical sideband suppression ratio and electrical spurious suppression ratio of the output microwave signal,as well as the effects of the phase balance of the 90°hybrid coupler on the phase drift and amplitude variation of the microwave signal are analyzed.