应用马赫-曾德尔调制器的光微波链路建模

在考虑马赫-曾德尔调制器(MZM)的消光比、双臂驱动不平衡度等非理想特性参量对其进行细致的理论建模的基础上,建立了包括光源、双臂驱动马赫-曾德尔调制器、光传输模块、光电探测器的基本光微波链路模型,并得到双边带调制(DSB)和单边带调制(SSB)链路的全阶解析响应结果,着重分析不同调制方式下马赫-曾德尔调制器对光微波链路幅度和相位(延时)性能的影响。理论计算和数值仿真结果表明,对双边带调制链路,消光比和双臂驱动不平衡度影响链路的幅频特性而不影响相位特性,对单边带调制链路,二者同时影响链路的幅频和相频特性。理论模型和数值结果可为使用马赫-曾德尔调制器的光微波系统如光纤无线电(RoF)和光控微波波束形成网络等提供定性和定量性能分析的基础。

Modelling of Fiber Radio Link Using Mach-Zehnder Modulator

Based on the detailed theoretical modelling of Mach-Zehnder Modulator(MZM),considering non-ideal parameters such as extinction ratio and driven-signal unbalanced ratio,a fundamental fibre radio link is presented including optical source,dual-electrode-drive MZM,optical transmission module and photodiode.The all-order analytic responses using dual side band(DSB) and single side band(SSB) modulation schemes are derived.The analysis concentrates on how MZM affects the amplitude and phase(time delay) response performance of a fibre radio link under different modulation modes.According to the theoretical and numerical results,the extinction ratio and driven-signal unbalanced ratio affect only the amplitude response performance of DSB modulation link but affect both the amplitude and the phase response performance of SSB modulation link.The theoretical model and numerical results can provide the basis of qualitative and quantitative analysis of fibre radio application system using MZM such as radio over fibre(RoF) and optical controlled microwave beam forming network.