基于射频功率谱的偏振模色散监测技术

Polarization Mode Dispersion Monitoring Technique Based on Radio Frequency Power Spectrum

基于偏振模色散(PMD)监测是光性能监测(OPM)中的一项关键技术。提出一种利用射频(RF)功率谱中功率极小值对应的频率值监测链路中PMD的方法。通过在接收端级联一段具有较大差分群时延(DGD)的保偏光纤(PMF)以及一个偏振控制器(PC)来实现在RF谱低频区域内监测PMD,并进行了相应的理论分析和数值仿真。结果表明,此方法可以实现对一阶偏振模色散的精确监测,监测误差在±3ps以内,且不受光信噪比(OSNR)、色散(CD)和传输速率的影响,同时此方法适用于多种调制格式的不同信号的PMD监测。通过改变接收端PMF中DGD的大小,可以满足对PMD监测范围和灵敏度的不同要求。

Polarization mode dispersion （PMD） is a key technology in optical performance monitoring （OPM）. A PMD monitoring method based on measuring the frequency of the minimum power of radio-frequency （RF） spectrum is proposed. By cascading a polarization maintaining optical fiber （PMF） with large differential group delay （DGD） and a polarization controller （PC） at the receiver, the PMD can be monitored in low frequency of RF spectrum, and relevant theoretical analysis and numerical simulation are also proceeded. The results demonstrate that this method can monitor first order PMD precisely with low monitoring error in ±3 ps. In addition, it is insensitive to the optical signal-to-noise ratio （OSNR）, chromatic dispersion （CD） and transmission rate. Varying the DGD in the PMF at the receiver, this method has different monitoring ranges and sensitivities.