一种新型多速率归零码全光帧时钟提取系统

A Novel Multi-Rate All-Optical Packet Clock Recovery System of Return-to-Zero Code

提出了一种新型的、低成本的多速率归零(RZ)码全光帧时钟提取方案。采用低精细度的法布里-珀罗滤波器(F-P)直接提取不同速率的帧时钟,保证帧时钟的快速建立和快速消失。利用不同的偏振延时干涉仪(PDI)和低自由光谱区(FSR)的法布里-珀罗滤波器构成组合滤波器以实现多速率帧时钟提取。利用半导体光放大器(SOA)的自增益调制效应(SGM)对组合滤波器提取的帧时钟进行整形,降低帧时钟的幅度噪声和时间抖动。实验中,利用光开关切换不同的偏振延时干涉仪构成不同自由光谱区的组合滤波器实现了10 GHz、20 GHz和40 GHz的帧时钟提取,得到了高质量、低时间抖动的多速率帧时钟信号。

We propose a novel, economical multi-rate all-optical packet clock extraction scheme of return-to-zero code, which comprises a Fabry-Pérot （F-P） filter, a semiconductor optical amplifier （SOA） and polarization dependent delay interferometers （PDIs）. Fabry-Pérot （F-P） filter with low finesse and low free spectral range was used to directly extract the multi-rate packet clock from the packet data stream, which ensures that the clock establishes and vanishes quickly. Different PDIs, combined with F-P filter was used to form comb filters with different FSRs to extract mult-rate packet clock. The packet clock then goes into SOA to reduce the low-frequency amplitude noise and temporal fluctuation with the self-gain modulation effect of SOA. We demonstrate instantaneous 10 GHz, 20 GHz and 40 GHz packet clock extraction experimentally by switching different PDI and forming filters with different FSR. Multi-rate packet clock signals with high quality and low temporal fluctuation are obtained.