Optimal power allocation for three-phase bidirectional DF relaying with fixed rates

Zoran Hadzi-Velkov, Nikola Zlatanov, Robert Schober

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearch

1 Citation (Scopus)


Wireless systems that carry delay-sensitive information (such as speech and/or video signals) typically transmit with fixed data rates, but may occasionally suffer from transmission outages caused by the random nature of the fading channels. If the transmitter has instantaneous channel state information (CSI) available, it can compensate for a significant portion of these outages by utilizing power allocation. In this paper, we consider optimal power allocation for a conventional dual-hop bidirectional decode-and-forward (DF) relaying system with a threephase transmission protocol. The proposed strategy minimizes the average power consumed by the end nodes and the relay, subject to some maximum allowable system outage probability (OP), or equivalently, minimizes the system OP while meeting average power constraints at the end nodes and the relay. We show that in the proposed power allocation scheme, the end nodes and the relay adjust their output powers to the minimum level required to avoid outages, but will sometimes be silent, in order to conserve power and prolong their lifetimes. For the proposed scheme, the end nodes use the instantaneous CSI of their respective sourcerelay links and the relay uses the instantaneous CSI of both links.

Original languageEnglish
Title of host publication10th IEEE International Symposium on Wireless Communication Systems 2013, ISWCS 2013
Subtitle of host publicationIlmenau, Germany; 27-30 August 2013
Place of PublicationPiscataway NJ USA
PublisherIEEE, Institute of Electrical and Electronics Engineers
Number of pages5
ISBN (Print)9783800735297
Publication statusPublished - 2013
Externally publishedYes
EventInternational Symposium on Wireless Communication Systems 2013 - Ilmenau, Germany
Duration: 27 Aug 201330 Aug 2013
Conference number: 10th


ConferenceInternational Symposium on Wireless Communication Systems 2013
Abbreviated titleISWCS 2013
Other10th IEEE International Symposium on Wireless Communication Systems 2013, ISWCS 2013

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