高速光纤通信系统调制技术仿真研究

Research and Simulation on Modulation Techniques in High-speed Optical Transmission System

构建了非归零码、归零码、载波抑制归零码、光双二进制码、改进的双二进制归零码等五种光强度调制格式在40Gb/s系统中的单信道传输模型,并采用OptiSystem7.0软件对其进行了仿真。分析比较了这五种调制格式的光谱图和眼图在非线性容限、色散容限、传输距离方面的优缺点,总结了它们的基本性能及应用场合。结果表明,MDRZ具有非线性容忍度最高、频谱效率高、色散容忍度较高及传输距离较远等特点,是高速光纤通信系统中很有潜力的调制格式。

Abstract. The transmitting models of five luminous intensity modulation formats, including non-return-to-zero （ NRZ）, return-to-zero （ RZ）, carrier-suppressed-return-to-zero （CSRZ）, optical-doubled-bit （ODB）, and modified-doubled-return-to-zero （MDRZ）, were constructed in the single channel of 40 Gb/s optical communication system. And OptiSystem 7.0 was applied to make simulations on the five models. The advantages and disadvantages of the five modulation formats were presented in terms of non-linear tolerance, dispersion tolerance and transmission distance by comparatively analyzing their spectrograms and eye patterns. And the fundamental characteristics and applications were summarized. Simulations results show that MDRZ owns highest non-linear tolerance, supreme frequency spectrum efficiency, superior dispersion tolerance as well as long transmission distance, which make it to be a significantly potential moudulation formats in thigh-speed optrican commromication system.