Method for estimation of chromatic dispersion in multichannel optical network spans and chromatic dispersion monitor therefore

• Main Authors: DeSalvo, Richard, Wilson, Arthur
• Format: Patent
• Language: English
• Published: 18.09.2003

The invention relates to a method for the estimation of chromatic dispersion in multichannel optical network spans during active operation. The invention further discloses a chromatic dispersion monitor for real time monitoring of accumulated dispersion in individual channels. The method effectively estimates accumulated chromatic dispersion by obtaining a contour map of the eye diagram correlating more than three points for measuring at least two parameters to known dispersion. This can provide accurate BER indication before failure occurs and provide indication of the sign of dispersion for faster correction. A chromatic dispersion monitor includes a high speed linear receiver to receive individual channel signals from a tunable filter, a clock recovery circuit with a variable time delay device for obtaining points to establish the contoured eye map and a processor for calculating metric values from the contoured eye map and correlating the calculated metric vales to a stored library of accumulated chromatic dispersion.