Optimized constellations for two-way wireless relaying with physical network coding
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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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Proceedings ArticleDOI
Distributed space time coding for wireless two-way relaying
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Journal ArticleDOI
Physical Layer Network Coding in Network MIMO: A New Design for 5G and Beyond
TL;DR: A design guideline of engineering applicable PNC to fulfil the request of high user densities in 5G wireless RAN infrastructure and develops a two-stage search algorithm to identify the optimum PNC mapping functions which greatly reduces the real-time computational complexity.
Proceedings ArticleDOI
Pairwise Check Decoding for LDPC Coded Two-Way Relay Fading Channels
TL;DR: The proposed PCD method is a practical and efficient realization of the promising denoise-and-forward relay strategy with advanced channel coding and non-linear network coding and incorporates adaptive network coding by using closest-neighbor clustering mapping (CNCM) to compensate the phase deviation of the fading channels.
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A Novel Machine-to-Machine Communication Strategy Using Rateless Coding for the Internet of Things
TL;DR: A novel coding strategy that considerably increases the efficiency of the channel in the multicast setting and an efficiently scalable technique for disseminating information among a large number of M2M communication devices is proposed.
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The Uplink of Distributed MIMO: Wireless Network Coding versus Coordinated Multipoint
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TL;DR: WNC in principle enables access point cooperation, combining the flows using network coding functions, instead of sending multiple separate information flows across the backhaul network, while providing superior performance compared with CoMP in terms of outage probability.
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