Cochannel Interference Whitening Receiver Designs for BPSK in Nakagami-m/Rayleigh Fading

The detection of a binary phase-shift keying signal distorted by like-modulated cochannel interference and noise using a noise-plus-interference whitening matched filter (WMF) is considered. The interfering signals are assumed to be independent and Rayleigh-faded. It is shown that in a synchronous channel, the signal-to-interference-plus-noise ratio (SINR) at the output of a WMF can not exceed that of the conventional matched filter (CMF) receiver. It is observed that in a synchronous channel, an interference WMF degrades the performance both through decreasing the SINR and introducing intersymbol interference (ISI). In contrast, in an asynchronous channel an optimal WMF can improve the SINR relative to the CMF receiver. It is shown that for a standard raised-cosine pulse the maximum achievable SINR gain over the CMF receiver is 1.76 dB. The SINR of the WMF receiver in asynchronous CCI is also evaluated for the case when a linear equalizer is used to mitigate the ISI caused by the WMF.