Non-Coherent Detection and Denoise-and-Forward Two-Way Relay Networks

• Published in: IEEE transactions on communications 2016-11, Vol.64 (11), p.4497-4505
• Main Authors: Masjedi, Maryam, Doost Hoseini, Ali Mohamad, Gazor, Saeed
• Format: Article
• Language: English
• Subjects: Amplitudes; Bit error rate; Channel estimation; Denoise-and-forward; Detectors; digital network coding; Fading; Network coding; Noise reduction; non-coherent detection; Optimization; Rayleigh channels; Relay networks; Relay networks (telecommunications); two-way relay networks; Upper bounds
• ISSN: 0090-6778; 1558-0857
• DOI: 10.1109/TCOMM.2016.2602829

We investigate non-coherent detection of M -ary orthogonal signaling in a denoise-and-forward two-way relay scheme in fast fading, as well as block fading channels. We first design the maximum likelihood, as well as maximum a-posteriori detectors, and then propose a simple suboptimal version for this digital network coding system in Rayleigh fast fading environment. We find exact expression of bit error rate for this suboptimal detector. Interestingly, this suboptimal detector performs only less than 0.25 dB away from optimum, i.e., this expression is a tight upper bound for the performance of the optimal one. Moreover, we derive the optimal detector for the case where the channel amplitudes are known at the relay. To make this detector practical, we propose efficient estimators for the channel amplitudes at the relay for block fading environments. Finally, our simulations reveal the effectiveness of the proposed methods compared with the state-of-the-art method.