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dc.contributor.authorGaeddert, Joseph Den_US
dc.date.accessioned2014-03-14T20:32:04Z
dc.date.available2014-03-14T20:32:04Z
dc.date.issued2005-02-07en_US
dc.identifier.otheretd-02222005-004616en_US
dc.identifier.urihttp://hdl.handle.net/10919/31309
dc.description.abstractThe detrimental effects rapid power fluctuation has on wireless narrowband communication channels has long been a concern of the mobile radio community as appropriate channel models seek to gauge link quality. Furthermore, advances in signal processing capabilities and the desire for spectrally efficient and low power radio systems have rekindled the interest for adaptive transmission schemes, hence some method of quickly probing the link quality and/or predicting channel conditions is required. Mathematical distributions for modeling the channel profile seek to estimate fading parameters from a finite number of discrete time samples of signal amplitude. While the statistical inference of such estimators has proven to be robust to rapidly shifting channel conditions, the benefits are quickly realized at the expense of processing complexity. Furthermore, computations of the best-known estimation techniques are often iterative, tedious, and complex. This thesis takes a renewed look at estimating fading parameters for the Nakagami-m, Rice-K, and Weibull distributions, specifically by showing that the need to solve transcendental equations in the estimators can be circumvented through use of polynomial approximation in the least-squared error sense or via asymptotic series expansion which often lead to closed-form and simplified expressions. These new estimators are compared to existing ones, the performances of which are comparable while preserving a lower computational complexity. In addition, the thesis also investigates the impact knowledge of the fading profile has on systems employing adaptive switching modulation schemes by characterizing performance in terms of average bit error rates (BER) and spectral efficiency. A channel undergoing Rice-$K$ fading on top of log-normal shadowing is simulated by correlating samples of received signal amplitude according to the user's doppler speed, carrier frequency, etc. The channel's throughput and BER performances are analyzed using the above estimation techniques and compared to non-estimation assumptions. Further discussion on narrowband fading parameter estimation and its applicability to wireless communication channels is provided.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartGaeddert_thesis.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectwirelessen_US
dc.subjectadaptiveen_US
dc.subjectriceen_US
dc.subjectadaptive modulationen_US
dc.subjectlognormal shadowingen_US
dc.subjectBER approximationsen_US
dc.subjectchannel estimationen_US
dc.subjectweibullen_US
dc.subjectradioen_US
dc.subjectnakagamien_US
dc.titleParametric Estimation of Stochastic Fading Channels and Their Role in Adaptive Radiosen_US
dc.typeThesisen_US
dc.contributor.departmentElectrical and Computer Engineeringen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
dc.contributor.committeechairAnnamalai, Annamalai Jr.en_US
dc.contributor.committeememberTranter, William H.en_US
dc.contributor.committeememberReed, Jeffrey Hughen_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-02222005-004616/en_US
dc.date.sdate2005-02-22en_US
dc.date.rdate2006-02-24
dc.date.adate2005-02-24en_US


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