  Consider a waveform channel where the transmitted signal is corrupted by
Wiener phase noise and additive white Gaussian noise (AWGN). A discrete-time
channel model that takes into account the effect of filtering on the phase
noise is developed. The model is based on a multi-sample receiver which, at
high Signal-to-Noise Ratio (SNR), achieves a rate that grows logarithmically
with the SNR if the number of samples per symbol grows with the square-root of
the SNR. Moreover, the pre-log factor is at least 1/2 in this case.
