公开(公告)号：US20040208525A1

公开(公告)日：2004-10-21

申请号：US10057896

申请日：2002-01-29

Applicant: NORTEL NETWORKS LIMITED

Inventor： Saeid Seydnejad ,  Frederic F. Simard ,  Yunjun Zhang

IPC: H04B010/08 ,  H04J014/02

CPC classification number: H04J14/005 ,  H04B10/0775 ,  H04B2210/075

Abstract: Optical performance monitoring of a dense wave division multiplex optical communication system is immune to effects of stimulated Raman scattering. Each wavelength is modulated by an orthogonal spreading code dither signal having a predetermined modulation index. At a receiver, a portion of the aggregate optical signal is tapped and passes through a wavelength dependant optical delay filter. For each wavelength, the aggregate signal is multiplied by a synchronized copy of a respective spreading code and an autocorrelator detects the modulation power of the spreading code dither. The system can also be deployed as an optical reflectometer. For each autocorrelator, an aggregate reflected signal is multiplied by a copy of a spreading code having a respective different time delay. The distance to a reflection can be estimated from the time delay that yields the highest autocorrelation value.

Abstract translation: 密集波分复用光通信系统的光学性能监测免受受激拉曼散射的影响。 每个波长由具有预定调制指数的正交扩频码抖动信号调制。 在接收机处，聚合光信号的一部分被抽头并通过依赖于波长的光学延迟滤波器。 对于每个波长，聚合信号乘以相应扩展码的同步副本，并且自相关器检测扩展码抖动的调制功率。 该系统也可以部署为光学反射计。 对于每个自相关器，聚合反射信号乘以具有各自不同时间延迟的扩展码的副本。 可以从产生最高自相关值的时间延迟估计到反射的距离。