Abstract:

The existing representative timing recovery schemes is analyzed. And according to their problems of high requirement of sample rate and nonalldigital implementation a new alldigital timing recovery scheme is presented for highspeed optical coherent receiver which combines Gardner timingerror detector and interpolator. The new scheme has a series of advantages, such as low complexity and alldigital realization, etc. Also, the good performance of the new scheme is demonstrated in a 112Gbit/s polarization multiplexed nonreturntozero differential quadrature phaseshift keying (PMNRZDQPSK) transmission system.

Key words: 100 Gbit/s, optical coherent receiver, all digital timing recovery, equalization and polarization de multiplexing