DocumentCode :
931785
Title :
Opportunistic Spectral Usage: Bounds and a Multi-Band CSMA/CA Protocol
Author :
Sabharwal, Ashutosh ; Khoshnevis, Ahmad ; Knightly, Edward
Author_Institution :
Rice Univ., Houston
Volume :
15
Issue :
3
fYear :
2007
fDate :
6/1/2007 12:00:00 AM
Firstpage :
533
Lastpage :
545
Abstract :
In this paper, we study the gains from opportunistic spectrum usage when neither sender or receiver are aware of the current channel conditions in different frequency bands. Hence to select the best band for sending data, nodes first need to measure the channel in different bands which takes time away from sending actual data. We analyze the gains from opportunistic band selection by deriving an optimal skipping rule, which balances the throughput gain from finding a good quality band with the overhead of measuring multiple bands. We show that opportunistic band skipping is most beneficial in low signal to noise scenarios, which are typically the cases when the node throughput in single-band (no opportunism) system is the minimum. To study the impact of opportunism on network throughput, we devise a CSMA/CA protocol, multi-band opportunistic auto rate (MOAR), which implements the proposed skipping rule on a per node pair basis. The proposed protocol exploits both time and frequency diversity, and is shown to result in typical throughput gains of 20% or more over a protocol which only exploits time diversity, opportunistic auto rate (OAR).
Keywords :
carrier sense multiple access; channel capacity; diversity reception; protocols; wireless channels; capacity bounds; channel conditions; frequency bands; frequency diversity; multiband CSMA/CA protocol; multiband opportunistic auto rate; network throughput; node throughput system; opportunistic access; opportunistic band selection; opportunistic band skipping; opportunistic spectral usage; optimal skipping rule; time diversity; Access protocols; Bandwidth; Data analysis; Frequency; Gain measurement; Media Access Protocol; Multiaccess communication; Throughput; Time measurement; Transmitters; 802.11; CSMA/CA; Capacity bounds; measurement overhead; multi-channel; opportunistic access;
fLanguage :
English
Journal_Title :
Networking, IEEE/ACM Transactions on
Publisher :
ieee
ISSN :
1063-6692
Type :
jour
DOI :
10.1109/TNET.2007.893230
Filename :
4237154
Link To Document :
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