高速光纤网络中PMD的测试和补偿

偏振色散是光纤中的一种物理现象，它导致光脉冲随着时间扩散。如果扩散（散射）量过多，邻近的光脉冲将相互交迭和干涉。当接收器不能区分邻近位时，这种干涉将表现为高误码率（BER）。随着位间隔的降低，像在高速数据网络中那样，如10Gbit/s(OC-192,STM-64)或40Gbit/s(OC-768,STM-256)，过度的PMD将严重影响网络运营，本解释怎样通过准确测量和补偿PMD把这些副作用降到最低甚至排除。

Measuring and Compensating for PMD in High-Speed Optical Networks

Polarization mode dispersion is a physical phenomenon in optical fiber hatcauses light pulses to spread in time. If the amount of spread (dispersion) is excessive,adjacent light pulses will overlap and interfere with each other. This interference willmanifest itself as an increased bit error rate as the receiver may be unable to discernadjacent bits from each other. As the bit spacing decreases, as in high data-rate transmis-sions such as 10Gbit/s (OC-192, STM-64) or 40Gbit/s (OC-768, STM-256), excessive PMD willseverely impact network operation. This paper will explain how these negative effects can beminimized or eliminated through proper PMD measurement and compensation.