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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Journal ArticleDOI
Analog-Network-Coded Two-Way Relaying Under the Impact of CSI Errors and Network Interference
TL;DR: This paper characterize the interference affecting the aforementioned nodes by presenting a general model that incorporates the expected correlation of the interference process that affects the relay, which in turn affects the two sources and derives analytical formulas for the distribution of the signal-to-interference-plus-noise ratio (SINR).
Journal ArticleDOI
Toward Efficient 5G Transmission: SER Performance Analysis for Asynchronous Physical-Layer Network Coding
TL;DR: This paper performs analysis on SER of asynchronous PNC, considering both phase and symbol misalignments, and derives the lower and upper bounds, applicable to either multiuser detection-based network coding or belief propagation-based maximum a posteriori decoding.
Proceedings ArticleDOI
On Indexing of Lattice-Constellations for Wireless Network Coding with Modulo-Sum Decoding
Miroslav Hekrdla,Jan Sykora +1 more
TL;DR: It is shown that if indices form a modulo-arithmetic progression along each lattice (real) dimension (denoted Affine Indexing (AI)), the minimal distance of modulo’sum decoding equals to minimal Distance of primary terminal constellation.
Proceedings ArticleDOI
Hardware implementation of Distributed Learning Algorithm for mapping selection for Wireless Physical Layer Network Coding
TL;DR: In a two source, two relay and two destination network scenario this paper has implemented a non-cooperative game-based process that selects the WPLNC mapping of each individual relay node guaranteeing invertibility of WPL NC at the destinations as well as optimizing the relay's utility function, namely the output modulation cardinality.
Proceedings ArticleDOI
Linear physical layer network coding for multihop wireless networks
Alister G. Burr,Dong Fang +1 more
TL;DR: The use of integer rings, integer fields, binary extension fields and the ring of binary matrices as potential algebraic constructs are considered, and it is shown that the ring constructs provide more flexibility and the capacity benefits of the more flexible rings.
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