Show simple item record

dc.contributor.authorCheng, Xiaolinen_US
dc.date.accessioned2014-03-14T20:40:03Z
dc.date.available2014-03-14T20:40:03Z
dc.date.issued2005-06-15en_US
dc.identifier.otheretd-06152005-200425en_US
dc.identifier.urihttp://hdl.handle.net/10919/33590
dc.description.abstractAs developments in wireless ad hoc networks continue, there is an increasing expectation with regard to supporting content-rich multimedia communications (e.g., video) in such networks, in addition to simple data communications. The recent advances in multiple description (MD) video coding have made it highly suitable for multimedia applications in such networks. In this thesis, we study three important problems regarding multiple description video communications in wireless ad hoc networks. They are multipath routing for MD video, MD video multicast, and joint routing and server selection for MD video in wireless ad hoc networks. In multipath routing for MD video problem, we follow an applicationcentric cross-layer approach and formulate an optimal routing problem that minimizes the application layer video distortion. We show that the optimization problem has a highly complex objective function and an exact analytic solution is not obtainable. However, we find that a metaheuristic approach such as Genetic Algorithms (GAs) is eminently effective in addressing this type of complex cross-layer optimization problems. We provide a detailed solution procedure for the GA-based approach, as well as a tight lower bound for video distortion. We use numerical results to compare this approach to several other approaches and demonstrate its superior performance. In MD video multicast problem, we take the similar application-centric, cross-layer approach as in the multipath routing problem. We propose an MD video multicast scheme where multiple source trees are used. Furthermore, each video description is coded into multiple layers in order to cope with diversity in wireless link bandwidths. Based on this multicast model, we formulate the multicast routing as a combinatorial optimization problem and apply Genetic Algorithm (GA)-based metaheuristic procedure to solove this problem. Performance comparisons with existing approaches show significant gains for a wide range of network operating conditions. In the last problem, we study the important problem of joint routing and server selection for MD video in ad hoc networks. We formulate the task as a combinatorial optimization problem and present tight lower and upper bounds for the achievable distortion. The upper bound also provides a feasible solution to the formulated problem. Our extensive numerical results show that the bounds are very close to each other for all the cases studied, indicating the near-global optimality of the derived upper bounding solution. Moreover, we observe significant gains in video quality achieved by the proposed approach over existing server selection schemes. This justifies the importance of jointly considering routing and server selection for optimal MD video streaming in wireless ad hoc networks.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartthesis.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.subjectmultiple description videoen_US
dc.subjectvideo multicasten_US
dc.subjectwireless ad hoc networksen_US
dc.subjectserver diversityen_US
dc.subjectmultipath routingen_US
dc.subjectgenetic algorithmsen_US
dc.subjectcross-layer designen_US
dc.titleMultiple Description Video Communications in Wireless Ad Hoc Networksen_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.committeechairHou, Yiwei Thomasen_US
dc.contributor.committeememberReed, Jeffrey Hughen_US
dc.contributor.committeememberMidkiff, Scott F.en_US
dc.contributor.committeememberMao, Shiwenen_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-06152005-200425/en_US
dc.date.sdate2005-06-15en_US
dc.date.rdate2005-06-29
dc.date.adate2005-06-29en_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record