随着对光纤通信容量需求的不断增长，DWDM 系统和L 波段光器件成为当今研究的热点，多波长光源作为重要的有源器件倍受青睐。本文研究了基于Mach-Zehnder 结构的电光强度调制器的理论模型，利用公式仿真得到在一定微波功率调制下强度调制器输出的扩频光谱。实验研究了M-Z 结构的集成电光波导强度调制器光波长1550 nm 处10 GHz、15 GHz、20 GHz 扩频的实现，对理论分析所得的输出光谱与实际系统的输出光谱进行比较，发现谱线情况较一致。在调制频率10 GHz，调制深度C=1.39，V=2.98 V 时，输出光谱中可清楚观察到正负三阶等频率间隔的边波带，尤其是一阶边波带与中心波长峰值功率几乎相等，可实现三路光源等功率输出。

With the increasing demands for the capacity of fiber communication system nowadays，DWDM and L-band optical devices had become research hot spots．Moreover, multi-wavelength source has attracted more and more attention. The theory model of electro-optic intensity modulation based on the structure of Mach-Zehnder is illustrated. The output optical spectrum of broadening result is simulated and analyzed by the formulae while the microwave frequency and power are fixed. The 10 GHz, 15 GHz and 20 GHz frequency shift at 1 550 nm are obtained experimentally with a LiNbO3 waveguide. The spectrum calculated by theory agrees with the result of experimental system in real shape, and optical sidebands with equal frequency intervals are observed in the output spectrum in simulation. The third-order sidebands can be observed distinct when the frequency is 10 GHz, the modulation depth is 1.39 and the direct current bias voltage is 2.98 V. Particularly, the fundamental frequency and the first sideband obtain the same peak power means which can generate a three-wavelength optical source of excellence.