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Distributed space-time coding for two-way wireless relay networks

Cui, Tao and Gao, Feifei and Ho, Tracey and Nallanathan, Arumugam (2009) Distributed space-time coding for two-way wireless relay networks. IEEE Transactions on Signal Processing, 57 (2). pp. 658-671. ISSN 1053-587X.

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In this paper, we consider distributed space-time coding for two-way wireless relay networks, where communication between two terminals is assisted by relay nodes. Relaying protocols using two, three, and four time slots are proposed. The protocols using four time slots are the traditional amplify-and-forward (AF) and decode-and-forward (DF) protocols, which do not consider the property of the two-way traffic. A new class of relaying protocols, termed as partial decode-and-forward (PDF), is developed for the two time slots transmission, where each relay first removes part of the noise before sending the signal to the two terminals. Protocols using three time slots are proposed to compensate the fact that the two time slots protocols cannot make use of direct transmission between the two terminals. For all protocols, after processing their received signals, the relays encode the resulting signals using a distributed linear dispersion (LD) code. The proposed AF protocols are shown to achieve the diversity order of min{N,K}(1- (log log P/log P)), where N is the number of relays, P is the total power of the network, and K is the number of symbols transmitted during each time slot. When random unitary matrix is used for LD code, the proposed PDF protocols resemble random linear network coding, where the former operates on the unitary group and the latter works on the finite field. Moreover, PDF achieves the diversity order of min{N,K} but the conventional DF can only achieve the diversity order of 1. Finally, we find that two time slots protocols also have advantages over four-time-slot protocols in media access control (MAC) layer.

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Additional Information:© 2009 IEEE. Manuscript receivedMay 03, 2008; revised October 12, 2008; first published November 07, 2008; current version published January 30, 2009. This work has been supported in part by DARPA Grant N66001-06-C-2020, Caltech’s Lee Center for Advanced Networking, the Okawa Foundation Research Grant, and a gift from Microsoft Research, and the National University of Singapore and Defence Science and Technology Agency (DSTA), Singapore, under Grant R-263-000-447-232/123. This paper has been presented in part at the IEEE International Conference on Communications, Beijing, China, May 2008. The authors would like to thank the anonymous reviewers whose detailed comments have greatly improved the presentation of this paper.
Funding AgencyGrant Number
Caltech's Lee Center for Advanced NetworkingUNSPECIFIED
Okawa Foundation Research GrantUNSPECIFIED
Microsoft ResearchUNSPECIFIED
National University of SingaporeUNSPECIFIED
Defence Science and Technology Agency, SingaporeR-263-000-447-232/123
Subject Keywords:Rayleigh-fading channels; space–time coding; two-way channel; wireless relay networks
Record Number:CaltechAUTHORS:20090514-153538553
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:14222
Deposited By: Jason Perez
Deposited On:07 Aug 2009 19:18
Last Modified:22 Jun 2016 23:11

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