色散补偿方式对相位调制系统中相位噪声的影响

分别推导了相位调制系统中采用色散预补偿方式和后补偿方式下非线性相位噪声的计算公式,基于此对这两种色散补偿方式下的相位噪声、功率容限以及最优信号峰值功率进行了详细的分析和讨论,结果表明:采用色散预补偿方式较后补偿方式能更有效地抑制非线性相位噪声,其对非线性相位噪声的抑制能力随着信号能量、放大自发辐射(ASE)的功率谱密度以及传输距离的增加而提高;同时,色散预补偿系统具有更高的功率容限;色散的作用使系统的最优信号峰值功率增大,最佳相移大于1rad;色散预补偿系统的最优信号峰值功率大于色散后补偿系统。

Influence of Dispersion Compensation Schemes on Phase Noise of Phase Modulation Systems

The formulas for calculating nonlinear phase noise are proposed for both dispersion pre-compensation and post-compensation schemes. Based on these formulas, the phase noise, power tolerance and optimal signal peak power of both dispersion compensation schemes are analyzed and discussed in detail, respectively. Compared with the post-compensation scheme, pre-compensation scheme is more effective in reducing the nonlinear phase noise. Its suppression ability is improved with signal energy, amplified spontaneous emission (ASE) power spectral density and transmission distance increasing. The pre-compensation system possesses higher power tolerance than post-compensation system, and the optimal signal power is increased when dispersion is taken into account, which results in the optimal phase shift greater than 1 rad. And the optimal signal power for pre-compensation system is larger than post-compensation system.