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
Superposition coding for wireless Butterfly Network with partial Network Side-Information
TL;DR: It is shown that by a proper optimization of its parameters (rates & power allocation of underlying SC messages), SC is able to achieve the upper bound of two-way rate in BN for both the zero and perfect N-SI case and moreover, it represents a viable solution even for the case where only partial N- SI is available at both destinations.
Journal ArticleDOI
Wireless Network-Coded Accumulate–Compute-and-Forward Two-Way Relaying
TL;DR: In this paper, the authors extend this approach to an accumulate-compute-and-forward protocol, which employs two phases: a multiple access (MA) phase consisting of two channel uses with independent messages in each channel use and a broadcast (BC) phase having one channel use.
Book ChapterDOI
Developments in Wireless Network Prototyping, Design, and Deployment: Future Generations
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Outage Analysis of Decode-and-Forward Two-Way Relay Selection With Different Coding and Decoding Schemes
TL;DR: This paper proposes a new TWDR selection scheme for the two-way decode-and-forward relay, and presents the diversity-multiplexing tradeoff for the considered decoding and coding schemes.
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Asynchronous Physical-layer Network Coding
Lu Lu,Soung Chang Liew +1 more
TL;DR: In this paper, a general framework for decoding at the receiver based on belief propagation (BP) was proposed and investigated for PNC, which can effectively deal with symbol and phase asynchronies while incorporating channel coding at the same time.
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