DocumentCode :
1285021
Title :
Spectrum Leasing via Cooperative Opportunistic Routing Techniques
Author :
Chiarotto, Davide ; Simeone, Osvaldo ; Zorzi, Michele
Author_Institution :
Dept. of Inf. Eng., Univ. of Padova, Padova, Italy
Volume :
10
Issue :
9
fYear :
2011
fDate :
9/1/2011 12:00:00 AM
Firstpage :
2960
Lastpage :
2970
Abstract :
A licensed multihop network that coexists with a set of unlicensed nodes is considered. Coexistence is regulated via a spectrum leasing mechanism that is based on cooperation and opportunistic routing. Specifically, the primary network consists of a source and a destination communicating via a number of primary relay nodes. In each transmission block, the next hop is selected in an on-line fashion based on the channel conditions (and thus the decoding outcome) in the previous transmissions, according to the idea of opportunistic routing. The secondary nodes may serve as extra relays, and hence potential next hops, for the primary network, but only in exchange for spectrum leasing. Namely, in return for their forwarding of primary packets, secondary nodes are awarded spectral resources for transmission of their own traffic. Secondary nodes enforce Quality-of-Service requirements in terms of rate and reliability when deciding whether or not to cooperate. Four policies that exploit spectrum leasing via opportunistic routing in different ways are proposed. These policies are designed to span different operating points in the trade-off between gains in throughput and overall energy expenditure for the primary network. Analysis is carried out for networks with a linear geometry and quasi-static Rayleigh fading statistics by using Markov chain tools. Different multiplexing techniques are considered for multiplexing of the primary and secondary traffic at the secondary nodes, namely orthogonal multiplexing (such as time, frequency or orthogonal code division multiplexing) and superposition coding. The optimality in terms of both throughput and primary energy consumption of superposition coding over all possible multiplexing strategies, for the given routing techniques, is proved. Finally, numerical results demonstrate the advantages of the proposed spectrum leasing solution based on opportunistic routing and illustrate the trade-offs between primary throughput and energy co- - nsumption.
Keywords :
Markov processes; cognitive radio; encoding; frequency division multiplexing; geometry; telecommunication network routing; time division multiplexing; Markov chain; cooperative leasing; cooperative opportunistic routing; energy consumption; frequency division multiplexing; licensed multihop network; linear geometry; orthogonal code division multiplexing; orthogonal multiplexing; primary network; primary packets; primary throughput; quality-of-service requirements; quasi-static Rayleigh fading statistics; reliability; spectral resources; spectrum leasing; superposition coding; time division multiplexing; Decoding; Quality of service; Receivers; Relays; Routing; Throughput; Transmitters; Cognitive radio networks; cooperative transmission; end-to-end throughput; opportunistic routing; property-rights; spectrum leasing; superposition coding;
fLanguage :
English
Journal_Title :
Wireless Communications, IEEE Transactions on
Publisher :
ieee
ISSN :
1536-1276
Type :
jour
DOI :
10.1109/TWC.2011.072011.101908
Filename :
5963798
Link To Document :
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