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dc.contributor.advisorHalverson, Don R.
dc.creatorVarma, Vishal V.
dc.date.accessioned2010-01-14T23:54:06Z
dc.date.accessioned2010-01-16T00:03:27Z
dc.date.available2010-01-14T23:54:06Z
dc.date.available2010-01-16T00:03:27Z
dc.date.created2008-12
dc.date.issued2010-01-14
dc.identifier.urihttp://hdl.handle.net/1969.1/ETD-TAMU-2008-12-85
dc.description.abstractRobustness of a system has been defined in various ways and a lot of work has been done to model the robustness of a system, but quantifying or measuring robustness has always been very difficult. In this research, we develop a framework for robust system architecture. We consider a system of a linear estimator (multiple tap filter) and then attempt to model the system performance and robustness in a graphical manner, which admits an analysis using the differential geometric concepts. We compare two different perturbation models, namely the gradient with biased perturbations (sub-optimal model) of a surface and the gradient with unbiased perturbations (optimal model), and observe the values to see which of them can alternately be used in the process of understanding or measuring robustness. In this process we have worked on different examples and conducted many simulations to find if there is any consistency in the two models. We propose the study of robustness measures for estimation/prediction in stationary and non-stationary environment using differential geometric tools in conjunction with probability density analysis. Our approach shows that the gradient can be viewed as a random variable and therefore used to generate probability densities, allowing one to draw conclusions regarding the robust- ness. As an example, one can apply the geometric methodology to the prediction of time varying deterministic data in imperfectly known non-stationary distribution. We also compare stationary to non-stationary distribution and prove that robustness is reduced by admitting residual non-stationarity. We then research and develop a robust iterative handoff algorithm, relating generally to methods, devices and systems for reselecting and then handing over a mobile communications device from a first cell to a second cell in a cellular wireless communications system (GPRS, W-CDMA or OFDMA). This algorithm results in significant decrease in amount of power and/or result is a decrease of break in communications during an established voice call or other connection, in the field, thereby outperforming prior art.en
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.subjectRobusten
dc.subjectSystem Architectureen
dc.subjectWirelessen
dc.subjectCellularen
dc.subjecthand-offen
dc.subjecthand-overen
dc.subjectnon-stationaryen
dc.subjectre-selectionen
dc.subjectgradienten
dc.subjectdistributionen
dc.subjectperturbationen
dc.subjectsignal processingen
dc.subjectdifferential geometryen
dc.titleRobust Framework for System Architecture and Hand-offs in Wireless and Cellular Communication Systemsen
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentElectrical and Computer Engineeringen
thesis.degree.disciplineElectrical Engineeringen
thesis.degree.grantorTexas A&M Universityen
thesis.degree.nameDoctor of Philosophyen
thesis.degree.levelDoctoralen
dc.contributor.committeeMemberKundur, Deepa
dc.contributor.committeeMemberZourntos, Takis
dc.contributor.committeeMemberBanerjee, Amarnath
dc.type.genreElectronic Dissertationen


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