A Novel Receiver Design With Joint Coherent and Non-Coherent Processing

Abstract

In this paper, we propose a novel splitting receiver, which involves a joint processing of coherently and non-coherently received signals. Using a passive RF power splitter, the received signal at each receiver antenna is split into two streams, which are then processed by a conventional coherent detection (CD) circuit and a power-detection (PD) circuit, respectively. The streams of the signals from all the receiver antennas are then jointly used for information detection. We show that the splitting receiver creates a 3-D received signal space due to the joint coherent and non-coherent processing. We analyze the achievable rate of a splitting receiver, which shows that the splitting receiver provides a rate gain of 3/2 compared with either the conventional (CD-based) coherent receiver or the PD-based non-coherent receiver in the high SNR regime. We also analyze the symbol error rate (SER) for practical modulation schemes, which shows that the splitting receiver achieves asymptotic SER reduction by a factor of at least <inline-formula> <tex-math notation="LaTeX">\sqrt {M}-1 </tex-math></inline-formula> for <inline-formula> <tex-math notation="LaTeX">M </tex-math></inline-formula>-QAM compared with either the conventional (CD-based) coherent receiver or the PD-based non-coherent receiver.