We investigate experimentally and via simulation, the monitoring of fiber link quality in a PON using optical coding technology. We discuss design issues for periodic coding and the optimal detection criteria. We develop a reduced-complexity maximum-likelihood sequence estimation (RC-MLSE) algorithm. We conduct experiments to validate our detection algorithm using four periodic encoders that we designed and fabricated. Error-free detection is confirmed for encoders with separation as small as 1 m. Using the experimental data for the encoder impulse responses, we conduct Monte Carlo simulations for realistic PON geographical distributions with randomly located customers, again with error-free detection. We investigate the effect of coverage area and network size (number of subscribers) on the computational efficiency of our algorithm. We provide a bound on the probability that any given network will cause the algorithm to take exorbitant time to monitor the network, i.e., the time-out probability. Finally, we highlight the importance of averaging to remedy the power/loss budget limitations in our monitoring system to support higher network sizes and longer fiber reaches.
© 2011 Optical Society of America
Original Manuscript: April 13, 2010
Manuscript Accepted: September 21, 2010
Published: December 27, 2010
Mohammad M. Rad, Habib A. Fathallah, Sophie LaRochelle, and Leslie A. Rusch, "Computationally Efficient Monitoring of PON Fiber Link Quality Using Periodic Coding," J. Opt. Commun. Netw. 3, 77-86 (2011)