On the Selection of a Sampling Filter Bandwidth for a Digital Data Detector

We consider here the problem of selecting the lowpass sampling bandwidth for a digital mechanization of a matchedfilter bit-synchronizer combination. In particular, if digital data at a rate R bits/second plus Gaussian noise is passed through a filter of bandwidth KR and then sampled at the Nyquist rate, i.e., 2 KR , then how small can we choose K without paying an appreciable penalty in the SNR performance of the data detector?