Cognitive radio performance optimisation through spectrum availability prediction

dc.contributor.advisorMaharaj, Bodhaswar Tikanath Jugpershaden
dc.contributor.emailsimonbarnes@ieee.orgen
dc.contributor.postgraduateBarnes, Simon Daniel
dc.date.accessioned2013-09-07T01:15:05Z
dc.date.available2012-10-01en
dc.date.available2013-09-07T01:15:05Z
dc.date.created2012-09-03en
dc.date.issued2012-10-01en
dc.date.submitted2012-06-27en
dc.descriptionDissertation (MEng)--University of Pretoria, 2012.en
dc.description.abstractThe federal communications commission (FCC) has predicted that, under the current regulatory environment, a spectrum shortage may be faced in the near future. This impending spectrum shortage is in part due to a rapidly increasing demand for wireless services and in part due to inefficient usage of currently licensed bands. A new paradigm pertaining to wireless spectrum allocation, known as cognitive radio (CR), has been proposed as a potential solution to this problem. This dissertation seeks to contribute to research in the field of CR through an investigation into the effect that a primary user (PU) channel occupancy model will have on the performance of a secondary user (SU) in a CR network. The model assumes that PU channel occupancy can be described as a binary process and a two state Hidden Markov Model (HMM) was thus chosen for this investigation. Traditional algorithms for training the model were compared with certain evolutionary-based training algorithms in terms of their resulting prediction accuracy and computational complexity. The performance of this model is important since it provides SUs with a basis for channel switching and future channel allocations. A CR simulation platform was developed and the results gained illustrated the effect that the model had on channel switching and the subsequently achievable performance of a SU operating within a CR network. Performance with regard to achievable SU data throughput, PU disruption rate and SU power consumption, were examined for both theoretical test data as well as data obtained from real world spectrum measurements (taken in Pretoria, South Africa). The results show that a trade-off exists between the achievable SU throughput and the average PU disruption rate. Significant SU performance improvements were observed when prediction modelling was employed and it was found that the performance and complexity of the model were influenced by the algorithm employed to train it. SU performance was also affected by the length of the quick sensing interval employed. Results obtained from measured occupancy data were comparable with those obtained from theoretical occupancy data with an average percentage similarity score of 96% for prediction accuracy (using the Viterbi training algorithm), 90% for SU throughput, 83% for SU power consumption and 71% for PU disruption rate.en
dc.description.availabilityunrestricteden
dc.description.departmentElectrical, Electronic and Computer Engineeringen
dc.identifier.citationBarnes, SD 2012, Cognitive radio performance optimisation through spectrum availability prediction, MEng dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/25908 >en
dc.identifier.otherC12/9/14/agen
dc.identifier.upetdurlhttp://upetd.up.ac.za/thesis/available/etd-06272012-184819/en
dc.identifier.urihttp://hdl.handle.net/2263/25908
dc.language.isoen
dc.publisherUniversity of Pretoriaen_ZA
dc.rights© 2012 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.en
dc.subjectTraining algorithm complexityen
dc.subjectTraffic densityen
dc.subjectSpectrum sensingen
dc.subjectSpectrum measurementsen
dc.subjectSecondary user performanceen
dc.subjectChannel switchingen
dc.subjectCognitive radio (CR)en
dc.subjectOccupancy modellingen
dc.subjectOpportunistic spectrum allocationen
dc.subjectPrediction accuracyen
dc.subjectUCTDen_US
dc.titleCognitive radio performance optimisation through spectrum availability predictionen
dc.typeDissertationen

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