Precise method of estimation of semiconductor laser phase-noise-to-intensity-noise conversion in dispersive fiber

In this paper a new method is presented for the estimation of an intensity noise induced by an interaction of a laser phase noise with a chromatic dispersion of an optical fiber. The idea is based on performing a reference measurement of the phase-to-intensity converted noise using a standard dispersion compensating module, and further scaling of obtained data to estimate the noise for different values of dispersion. The experimental validation of this method for various lasers and various lengths of dispersive fiber is presented, and a noise optimization of a real link is briefly described. Proposed method is efficient laboratory tool allowing evaluation of the influence of the phase noise of particular laser on transmitted signals in all cases where it is important, e.g. in fiber optic bidirectional time and frequency transfer. (C) 2015 Elsevier Ltd. All rights reserved.