A Detailed Comparison of Four Approaches to the Calculation of the Sensitivity of Optical Fiber System Receivers

Abstract

In this paper four approaches to the calculation of error rates for optical fiber system repeaters are compared (Exact calculation, Monte Carlo simulation, Chernoff bounds and the Gaussian approximation). We conclude that the Exact and Monte Carlo calculations are in complete agreement. This allows the Monte Carlo results to be used to calibrate other methods. The relatively simple Chernoff bound is in very good agreement with the above, and should be used whenever computational facilities allow. For simpler calculations, or analytical expressions for the effects of parameter variations, the Guassian approximation gives a reasonable good estimate of the receiver sensitivity. However, it tends to underestimate the threshold setting and overestimate the optimal avalanche gain.