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。 The single-channel transmission model of 40Gb / s optical systems with non-return-to-zero codes, zero return codes, carrier suppression zeroing codes, optical double binary codes and improved double binary zeroing codes was constructed and adopted OptiSystem7.0 software to simulate it. The advantages and disadvantages of the spectrogram and the eye diagram of these five modulation formats in nonlinear tolerance, dispersion tolerance and transmission distance are analyzed and compared, and their basic performances and applications are summarized. The results show that MDRZ has the characteristics of high nonlinearity tolerance, high spectral efficiency, high dispersion tolerance and long transmission distance. It is a potential modulation format in high speed optical fiber communication systems.