Optimizing a matched filter in the presence of ISI and adjacent channel interference

QAM based communications systems suffer performance loss due to the practical implementation of the matched filter in the receiver. The practical matched filter causes two types of interference: Intersymbol Interference and Adjacent Channel Interference. The combined effect of the interference is minimized by applying a tapered window to the matched filter coefficients. It is shown that proper windowing improves the modulation error ratio by 0.5 to 8 dB depending upon the adjacent channel power.