System Limitations for Fiber Amplifier Cascades

Abstract

The performance of an amplifier cascade system is taken to be the product of transmission bit rate, B, and transmission distance, L. In amplifier cascade systems using the IM/DD scheme, signal spontaneous beat noise, spontaneous-spontaneous beat noise and shot noise are present in addition to receiver thermal noise, while local oscillator shot noise and local oscillator-spontaneous beat noise are additional factors in coherent systems. Signal-spontaneous and spontaneous-spontaneous beat noises generally predominate in IM/DD systems if many cascaded amplifiers are used.