Abstract

Mode partition noise may become one of the fundamental performance limitations^1,2 for single-mode fiber systems. This noise is caused by the Instantaneous fluctuation of the power distribution among the laser longitudinal modes and the differential delay of the longitudinal modes due to chromatic dispersion. Since this noise is a generic function of the laser spectral distribution and the fiber chromatic dispersion, the SNR due to this noise is independent of the signal power. The error rate, therefore, approaches a floor value (asymptotic error rate) as the optical power is increased. We derived a simple formula describing mode partition noise based on two basic assumptions: (1) that the total power of each pulse is constant and (2) that the partition probability function is based on the time averaged spectral distribution. Figure 1 shows the analytic result for the bit rate-distance-mode partition coefficient product (asymptotic error rate of 10⁻⁹) for a silica single-mode fiber (minimum dispersion wavelength = 1.3 μm) due to the mode partition noise.

© 1982 Optical Society of America