Use of tapped delay line filter in digital transmission systems

The probability of error was found analytically by the averaging method for a PCM/NRZ digital transmission system under the influence of intersymbol interference and additive Gaussian noise. Two receiver structures were studied; an in- tegrate-and-dump detector receiver and an intergrate-and- dump with tapped delay line filtering. The two receivers were implemented in order to obtain experimental results for comparison with calculated results. The analytical and experimental results were also compared to results for other receiver structures suggested by other investigators. The receiver structure that was found to give near optimum performance consisted of an integrate-and-dump detector with a one-tap tapped delay line filter operating at a bandwidth-time duration product equal to 0.8.