Optimized constellations for two-way wireless relaying with physical network coding
TLDR
The proposed modulation scheme can significantly improve end-to-end throughput for two-way relaying systems and is applicable to a relaying system using higher-level modulations of 16QAM in the MA stage.Abstract:
We investigate modulation schemes optimized for two-way wireless relaying systems, for which network coding is employed at the physical layer. We consider network coding based on denoise-and-forward (DNF) protocol, which consists of two stages: multiple access (MA) stage, where two terminals transmit simultaneously towards a relay, and broadcast (BC) stage, where the relay transmits towards the both terminals. We introduce a design principle of modulation and network coding, considering the superposed constellations during the MA stage. For the case of QPSK modulations at the MA stage, we show that QPSK constellations with an exclusive-or (XOR) network coding do not always offer the best transmission for the BC stage, and that there are several channel conditions in which unconventional 5-ary constellations lead to a better throughput performance. Through the use of sphere packing, we optimize the constellation for such an irregular network coding. We further discuss the design issue of the modulation in the case when the relay exploits diversity receptions such as multiple-antenna diversity and path diversity in frequency-selective fading. In addition, we apply our design strategy to a relaying system using higher-level modulations of 16QAM in the MA stage. Performance evaluations confirm that the proposed scheme can significantly improve end-to-end throughput for two-way relaying systems.read more
Citations
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Journal Article
Analysis of Antenna Selection in Two-way Relaying MIMO Systems with CPM Modulation
TL;DR: In this article, the performance of joint transmit and receive antenna selection (JTRAS) with continuous phase modulation (CPM) in two-way relaying MIMO systems is analyzed.
Dissertation
Power optimization, network coding and decision fusion in multi-access relay networks
TL;DR: This thesis develops the optimal power allocation, network coding and information fusion techniques to improve the performance of MAR channel by considering certain criterion (e.g., minimizing the average symbol error rate (SER) or maximizing the average sum-rate).
Journal ArticleDOI
Closed-Form Differential Hierarchical Demodulator of 2-Source Hierarchical-MAC Channel
Petr Hron,Jan Sykora +1 more
TL;DR: This letter proposes multiple suboptimal closed-form differential demodulation methods which do not require explicit phase estimation and thus substantially simplify the receiver processing and measures the resulting hierarchical bit error rate for all proposed demodulated methods.
Proceedings ArticleDOI
Wireless bidirectional relaying using Physical Layer Network Coding with heterogeneous PSK modulation
TL;DR: In this article, when users employ heterogeneous symmetric-PSK modulations, the network coding maps and the mapping regions in the fade state plane can be obtained analytically.
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