Nonlinearity analysis of DFB laser in CATV systems with discrete Fourier transform method

摘要

Abstract: In this paper, we present a novel method for analyzing the nonlinearity of the DFB laser. The method is based on a spectrum analysis with discrete Fourier transform on the model of laser mapping functions. In the view of the signal analysis, it avoids using some semiconductor parameters that are difficult to obtain but necessary for analyzing in the method. The algorithm together with the mapping function derived from the measurement can examine the harmonic and intermodulation distortions of laser chip and laser module. The comparison between the measurement and calculation shows that the algorithm is simple and effective for laser distortion analysis. The method is also applied to simulate the property of DFB laser and evaluate the linear request for the laser chips.!5