Analysis of BER Performance of the Fiber-optic Communication System with IMDD when using CP-OFDM Signals

This article discusses the combined use of signals with orthogonal frequency-division multiplexing (OFDM) and intensity modulation with direct detection (IMDD) for a fiber-optic communication system. The purpose of this work is to determine the effective values of the system parameters. With the help of simulation modeling in MATLAB, the reception noise immunity was determined for various scenarios under conditions of a fixed bit rate. A Bessel filter was used to simulate the effect of electrical circuits on the signal. The chromatic dispersion of the fiber was considered when modeling the optical channel. As a result of the study, a set of parameters was determined that provides the lowest signal-to-noise ratio per bit (SNR) to achieve a bit error rate (BER) of 0.01, in particular, the number of data subcarriers (SC), the length of the cyclic prefix (CP) and the value of the direct current of the laser (DC).