Improved analysis of dispersion penalty in optical fibre systems

Based on the model presented by Campbell [1], simple and convenient formulae are developed for calculating the dispersion penalty with consideration of the system pulse shaping, the laser diode spectrum and the different statistics of mode partition noise within and between baud periods. Numerical calculations show that they are good approximations of the complex expressions given by Campbell. Furthermore, we show that Ogawa's mode partition noise expressions in [2] should be corrected by a factor of about 2 and the wave shape at decision should be carefully designed to minimize the mode partition noise.