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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Proceedings ArticleDOI
Performance analysis of OFDM-Based denoise-and-forward full-duplex PLNC with imperfect CSI
TL;DR: It is demonstrated that the proposed FD-PLNC scheme can increase the throughput of the conventional TWRC network by a factor of 4 and the throughputOf the half-duplex physical-layer network coding (HD-PL NC) by a factors of 2.
Journal ArticleDOI
Maximum euclidean distance network coded modulation for asymmetric decode-and-forward two-way relaying
Wei Chen,Zhigang Cao,Lajos Hanzo +2 more
TL;DR: This contribution proposes set-partitioning-based NCM as an universal concept which can be combined with arbitrary constellations and conceive practical phase-shift keying/quadrature amplitude modulation (PSK/QAM) NCM schemes, referred to as network coded PSK/ QAM, based on modulo addition of the normalised phase/amplitude.
Proceedings ArticleDOI
Relay Selection with Physical-Layer Network Coding
MinChul Ju,Il-Min Kim +1 more
TL;DR: This work proposes a relay selection scheme by modifying the well-known selection cooperation (SC) to use in the PNC protocol, and it is referred to as SC-PNC, and the exact outage probability is derived in closed-form.
Proceedings ArticleDOI
Pseudo Exclusive-OR for LDPC Coded Two-Way Relay Block Fading Channels
TL;DR: Simulation results show that the proposed coded PXOR considerably outperforms the coded conventional XOR and achieves the same performance as the complicated coded CNC for considered two TWR block fading channels.
Journal ArticleDOI
Antenna selection for two-way full duplex massive MIMO networks with amplify-and-forward relay
TL;DR: This paper investigates the antenna selection problem for the relaying system with the base station having massive multiple antennas, where the relay station works in the full duplex mode and the two-way protocol.
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