Novel approach for reducing the probability of error in the presence of intersymbol interference and Gaussian noise

A novel method to reduce the probability of error in the presence of inter-symbol interference (ISI) and additive Gaussian noise is introduced. The proposed technique is based on modifying the characteristic function of the ISI variable used in the Beaulieu series method to evaluate the probability of error for binary symmetric channels, such that some pulses are omitted to reduce the effect of ISI. This is accomplished by mapping words of certain bit lengths to prescribed series of pulses where some of the pulses are omitted (zeros). The probability of error for the proposed method is evaluated for different word lengths using Gaussian pulses. Test results show that certain pulse series of lengths 12 or greater, with free distances of two or more and consisting of 30% zeros or more, would achieve lower probability of error in the presence of ISI and Gaussian noise. (C) 2007 Society of Photo-Optical Instrumentation Engineers.