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Graph-based codes for Quantize-Map-and-Forward relaying

Ayan Sengupta, Siddhartha Brahma, Ayfer Ozgur, Christina Fragouli, Suhas Diggavi
2011 2011 IEEE Information Theory Workshop  
We present a structured Quantize-Map-and-Forward (QMF) scheme for cooperative communication over wireless networks, that employs LDPC ensembles for the node operations and message-passing algorithms for  ...  and achieves the full diversity order of our network at moderate SNRs.  ...  INTRODUCTION Quantize-Map-and-Forward (QMF) is a recently proposed strategy that allows to approximately achieve the capacity of arbitrary wireless relay networks [2] .  ... 
doi:10.1109/itw.2011.6089363 dblp:conf/itw/SenguptaBOFD11 fatcat:je6sbt5u2zfn7o7dqga37mzqru

Quantize-map-and-forward relaying: Coding and system design

Vinayak Nagpal, I-Hsiang Wang, Milos Jorgovanovic, David Tse, Borivoje Nikolic
2010 2010 48th Annual Allerton Conference on Communication, Control, and Computing (Allerton)  
Quantize-map-and-forward (QMF) is a relaying scheme that has been shown to achieve the capacity of Gaussian relay networks to within a constant gap.  ...  For suitable choice of codes and quantizer we show that the joint decoding operation for QMF can be reduced to belief propagation over a Tanner graph.  ...  The framework is based on LDPC codes for encoding at the source and mapping at the relay.  ... 
doi:10.1109/allerton.2010.5706940 fatcat:hsmazkynhre23ids4vvs4jxplm

Coding and system design for quantize-map-and-forward relaying

Vinayak Nagpal, I-hsiang Wang, Milos Jorgovanovic, David Tse, Borivoje Nikolic
2013 IEEE Journal on Selected Areas in Communications  
In this paper we develop a low-complexity coding scheme and system design framework for the half duplex relay channel based on the Quantize-Map-and-Forward (QMF) relay- ing scheme.  ...  We propose the use of binary LDPC codes for encoding at the source and LDGM codes for mapping at the relay.  ...  We propose a system design and coding framework for quantize-map-and-forward (QMF) [1] relaying that has low complexity and performs close to information theoretic bounds. A.  ... 
doi:10.1109/jsac.2013.130807 fatcat:mzqtkypg4vfb5mgw7hqr6elb44

Coding and system design for quantize-map-and-forward relaying

Vinayak Nagpal, I-hsiang Wang, Milos Jorgovanovic, David Tse, Borivoje Nikolic
2013 IEEE Journal on Selected Areas in Communications  
In this paper we develop a low-complexity coding scheme and system design framework for the half duplex relay channel based on the Quantize-Map-and-Forward (QMF) relaying scheme.  ...  We propose the use of binary LDPC codes for encoding at the source and LDGM codes for mapping at the relay.  ...  We propose a system design and coding framework for quantize-map-and-forward (QMF) [1] relaying that has low complexity and performs close to information theoretic bounds. A.  ... 
doi:10.1109/jsac.2013.6658244 fatcat:ccvihnlnfrcodkohwmosn2hhiu

Joint network-channel coding for the asymmetric multiple-access relay channel

Andreas Winkelbauer, Gerald Matz
2012 2012 IEEE International Conference on Communications (ICC)  
We propose a low-complexity compress-and-forward-based transmission scheme that consists of a scalar quantization of log-likelihood ratios (LLRs), followed by a suitably defined network code.  ...  We use the information bottleneck method (IBM) for designing the LLR quantizers and we propose a modified IBM algorithm with more favorable numerical properties.  ...  CONCLUSIONS We have proposed a transmission scheme for the MARC based on CF with optimal LLR quantization at the relay.  ... 
doi:10.1109/icc.2012.6364440 dblp:conf/icc/WinkelbauerM12 fatcat:fe7nokz5lbf4hanqxoqvxhap6a

Regenerative and Adaptive schemes Based on Network Coding for Wireless Relay Network

Ahmed Hassan M. Hassan
2012 International Journal of Computer Networks & Communications  
at relay node; it works directly to De-map the received signals and after that forward the mixture to the destination.  ...  Recent technological advances in wireless communications offer new opportunities and challenges for relay network.To enhance system performance, Demodulate-Network Coding (Dm-NC) scheme has been examined  ...  In [9] have proposed scheme known as quantized maps-and-forward (QMF) to quantizes the received signal at the noise level and generates a new version of mapping signal before forwarding to destination  ... 
doi:10.5121/ijcnc.2012.4305 fatcat:2k4ex4tqzrcm3ndmzuntmdtq3m

An adaptive compress-and-forward scheme for the orthogonal multiple-access relay channel

Georg Zeitler, Ralf Koetter, Gerhard Bauch, Joerg Widmer
2009 2009 IEEE 20th International Symposium on Personal, Indoor and Mobile Radio Communications  
Based on the expression for the achievable rate in such a network for compress-and-forward relaying without Wyner-Ziv coding, we design mutual-information preserving quantizers for compression at the relay  ...  In the proposed relaying scheme, both the relay and the destination share a fixed set of quantizers, among which the relay selects a suitable one depending on the channel quality on the source-relay links  ...  Design of compression schemes for compress-and-forward in the relay channel with a single source was studied in [10] and [11] with and without Wyner-Ziv coding, respectively.  ... 
doi:10.1109/pimrc.2009.5449851 dblp:conf/pimrc/ZeitlerKBW09 fatcat:5fdh54bk5nb6tbjto3l7lns6z4

Compress-and-Forward Scheme for Relay Networks: Backword Decoding and Connection to Bisubmodular Flows

Adnan Raja, Pramod Viswanath
2014 IEEE Transactions on Information Theory  
In this paper, a compress-and-forward scheme with backward decoding is presented for the unicast wireless relay network.  ...  The encoding at the source and relay is a generalization of the noisy network coding scheme (NNC).  ...  ACKNOWLEDGMENTS The authors would like to thank Chandra Chekuri for the many useful discussions.  ... 
doi:10.1109/tit.2014.2334328 fatcat:f2w5aff2d5eg3ennddqkdps3jm

Quantize-and-Forward Schemes for the Orthogonal Multiple-Access Relay Channel

Georg Zeitler, Gerhard Bauch, Jorg Widmer
2012 IEEE Transactions on Communications  
Quantize-and-Forward Schemes for the Orthogonal Multiple-Access Relay Channel I.  ...  [12] , where the relay computes soft information about the network coded code bits based on ( 1 , 2 ).  ... 
doi:10.1109/tcomm.2012.020612.100096 fatcat:htefr4trbbejpnk4df4btdvrtu

A soft information delivery scheme in two-way relay channels with network coding

Yiwen Li, Zihuai Lin, Jun Li, Branka Vucetic
2013 2013 IEEE 24th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC)  
The soft network coded symbols are quantized into only one bit thus requiring the same transmission bandwidth as the simplest decode-and-forward (DF) protocol.  ...  In this thesis, a practical two-way transmission scheme is proposed based on the EF protocol and the network coding technique.  ...  Hence relay protocols targeting at TWRC have emerged, including an EF based soft network coding protocol proposed in [38] , and two MIF based protocols, namely, network-coded MIF and superposition-coded  ... 
doi:10.1109/pimrc.2013.6666112 dblp:conf/pimrc/LiLLV13 fatcat:eaj67iw2hvam3axmcspwdk5iu4

Joint network-channel coding in the multiple-access relay channel: Beyond two sources

Andreas Winkelbauer, Gerald Matz
2012 2012 5th International Symposium on Communications, Control and Signal Processing  
The combination of log-likelihood ratio (LLR) quantization and network coding was previously shown to be a promising compressand-forward strategy for the multiple access relay channel with two sources.  ...  Our proposed relay scheme consists of a scalar LLR quantizer for each source followed by a network coding (NC) step that suitably combines the quantizer outputs.  ...  QUANTIZATION AND NETWORK CODING LLR Quantization The relay uses N scalar quantizers Qi(·) to map the LLRs Λ (dec) i ∈ R L to index vectors qi ∈ Q L i , where q i,k = Qi(Λ (dec) i,k ).  ... 
doi:10.1109/isccsp.2012.6217859 dblp:conf/isccsp/WinkelbauerM12 fatcat:gr2xufjatjgbbbkezeubdmdh64

Coarse Network Coding: A Simple Relay Strategy to Resolve Interference [article]

Peyman Razaghi, Giuseppe Caire
2010 arXiv   pre-print
Reminiscent of the parity function in network coding for the butterfly network, it is shown that forwarding an even/odd indicator bit for a scalar quantization of a relay observation recovers 1 bit of  ...  Based on this observation, a coding strategy is proposed to improve the rate of both users at the same time using a relay node in an interference channel.  ...  Moreover, not many practical compress-and-forward relay coding schemes are available, since the decode-and-forward scheme is often favored upon the compress-and-forward relay strategy for multihop relaying  ... 
arXiv:1009.1193v2 fatcat:xdfjah64b5aihchrqmlul7odhy

Performance Enhancement of Wireless Networks Using Cooperative Diversity Techniques

M.Keerthana Lakshmi, G.Sivakannu
2018 Zenodo  
In our proposed work, a network containing a sender, a destination and a fixed relay, is analyzed with modified cooperative diversity scheme such as Amplify-Quantize and Forward (AFQ) and compared with  ...  existing cooperative communication protocol i.e., Amplify and forward (AF).  ...  diversity protocols as a function of the SNR ratio for amplify and forward (AF) and amplify quantize and forward (AQF) of cooperative protocols and also outage probability analysis for fixed three nodes  ... 
doi:10.5281/zenodo.2446669 fatcat:yoifpvr4gnf2vgi7vcgjcgv5jy

Relay: A High-Level Compiler for Deep Learning [article]

Jared Roesch, Steven Lyubomirsky, Marisa Kirisame, Logan Weber, Josh Pollock, Luis Vega, Ziheng Jiang, Tianqi Chen, Thierry Moreau, Zachary Tatlock
2019 arXiv   pre-print
We present Relay, a new compiler framework for DL. Relay's functional, statically typed intermediate representation (IR) unifies and generalizes existing DL IRs to express state-of-the-art models.  ...  Our evaluation demonstrates Relay's competitive performance for a broad class of models and devices (CPUs, GPUs, and emerging accelerators).  ...  Instead, Relay includes a generic, compiler-based quantization flow that supports a diverse set of quantization mechanisms and automatically generate code for each of them.  ... 
arXiv:1904.08368v2 fatcat:edkc2clp6jdu7d6fceuoj7e4g4

On Quantizer Design for Soft Values in the Multiple-Access Relay Channel

G. Zeitler, R. Koetter, G. Bauch, J. Widmer
2009 2009 IEEE International Conference on Communications  
available for both sources at the relay.  ...  A network with two sources, one relay, and one destination is considered.  ...  at the destination [12] impossible, as suggested for the compress-and-forward [7] relaying strategy.  ... 
doi:10.1109/icc.2009.5199246 dblp:conf/icc/ZeitlerKBW09 fatcat:4fbfsd7tl5awrf7xx64xbariai
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