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 ArticleDOI
Outage Probability of Two-Way Full-Duplex Relaying With Imperfect Channel State Information
Dongwook Choi,Jae Hong Lee +1 more
TL;DR: This letter derives the exact integral and approximate closed-form expressions for the outage probability of the TWFD relaying in case of perfect and imperfect channel state information.
Journal ArticleDOI
Modified High-Order PAMs for Binary Coded Physical-Layer Network Coding
TL;DR: New modified high-order PAMs are presented that enable us to use the computationally efficient binary channel coding under the PNC over a DF relaying channel.
Journal ArticleDOI
Layered Design of Hierarchical Exclusive Codebook and Its Capacity Regions for HDF Strategy in Parametric Wireless 2-WRC
Jan Sykora,Alister G. Burr +1 more
TL;DR: This paper addresses a hierarchical decode-and-forward (HDF) strategy in the wireless two-way relay channel (2-WRC) that uses a Hierarchical eXclusive Code (HXC) that allows full decoding of the hierarchical symbols at the relay.
Journal ArticleDOI
Rate and Power Adaptation for Analog Network Coding
TL;DR: The simulation results show that the proposed joint rate and power adaptation scheme outperforms ANC without power adaptation and that it is beneficial over other relaying schemes in a broad range of scenarios of mobile and vehicular applications.
Journal ArticleDOI
A Linear Analog Network Coding for Asynchronous Two-Way Relay Networks
TL;DR: In this letter, an analog network coding (ANC) scheme for a time asynchronous two-way relay network is proposed, where each relay node linearly transforms the received mixed asynchronous signals in the first time-slot by a Toeplitz matrix.
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