Abstract
This paper reports on evaluation of the performance of optical fiber communication systems employing semiconductor lasers subjected to high-speed digital modulation. The evaluation is achieved in terms of the bit error rate and its dependence on the transmission bit rate. The study is based on numerical large-signal analysis of the laser rate equations and counting noise mechanisms in the receiver. Correlation between the bit error rate and the signal-quality factor is presented. The results show that under high speed modulation, the pseudorandom bit-pattern induces enhanced influence of laser noise to the bit error rate. Under low-speed modulation, contribution of laser noise to the bit error rate is mainly due to the intrinsic fluctuations in the "1" and "0" levels.