In-service dispersion monitoring technique using dithered-filter method and its application to fast adaptive compensation in reconfigurable optical networks

Abstract

ABSTRUCTWe describe an in-service dispersion monitoring technique which we call dithered-filter method and show its application to adaptive dispersion compensation. In the proposed method, we filter out a portion of the received signal light by a dithered optical band-pass filter and derive the accumulated dispersion from the phase shift of the extracted clock signal. This method does not require any modification of the transmitter, and is applicable to any modulation format as far as the clock signal is extracted. In addition, owing to the dithering and the synchronous detection, high accuracy is realized with a short measurement time less than 200 msec. In this paper, we explain the principle of operation of the proposed method and show the experimental demonstration of fast adaptive dispersion compensation in a 40 Gbit/s reconfigurable optical network.