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dc.contributor.authorAbdel-Rahman, Mohamed A.en_US
dc.date.accessioned2014-03-14T20:07:54Z
dc.date.available2014-03-14T20:07:54Z
dc.date.issued1997-12-17en_US
dc.identifier.otheretd-02898-04748en_US
dc.identifier.urihttp://hdl.handle.net/10919/26335
dc.description.abstract(ABSTRACT) A study is undertaken of the numerical reconstruction of acoustic and electromagnetic (EM) localized waves (LWs). The latter are carrier-free ultra-wideband pulses characterized by large focusing depths and extended ranges of localization. Special emphasis is placed on finite energy LWs that can be generated by dynamic aperture antennas with independently addressable elements. The reconstruction techniques are based on Huygens and Rayleigh-Sommerfeld integral I and II representations, both in the time and frequency domains. In contradistinction to the Weyl representation,they lend themselves to the physical realization of space-time aperture sources capable of generating localized wave solutions propagating away from the aperture plane. A detailed comparison of the three reconstruction techniques has been carried out in connection with LW solutions to the scalar wave equation, especially with respect to their handling of acausal components incorporated in the aperture excitation fields. In addition, a study is presented of the characteristic properties of LWs propagating through dispersive media modeled by the Klein-Gordon equation. It is demonstrated that contrary to expectation, the depletion of the spectral components of the LW Klein-Gordon field may be slower than that associated with the free space scalar field. Previous work by Power et al. [73] is extended by studying the acoustic bistatic scattering of a modified power spectrum (MPS) pulse from rigid and compressible spheres. The analysis allows the extraction of the radius of a sphere from the backscattered data. Finally, a special class of electromagnetic (EM) LWs, referred to as azimuthally polarized X waves (APXWs), is derived and their reconstruction is addressed, both in the time and frequency domains.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartetd.pdfen_US
dc.relation.haspartch1.pdfen_US
dc.relation.haspartch2.pdfen_US
dc.relation.haspartch3.pdfen_US
dc.relation.haspartch4.pdfen_US
dc.relation.haspartch5.pdfen_US
dc.relation.haspartch6.pdfen_US
dc.relation.haspartref.pdfen_US
dc.relation.haspartvita.pdfen_US
dc.rightsI hereby grant to Virginia Tech or its agents the right to archive and to make available my thesis or dissertation in whole or in part in the University Libraries in all forms of media, now or hereafter known. I retain all proprietary rights, such as patent rights. I also retain the right to use in future works (such as articles or books) all or part of this thesis or dissertation.en_US
dc.subjectAcoustic and Electromagnetic Localized Pulsesen_US
dc.subjectDynamic Aperture Antennasen_US
dc.subjectHuygens and Rayleigh-Sommerfeld Reconstructionen_US
dc.subjectPlasmaen_US
dc.subjectBistatic Scatteringen_US
dc.subjectRemote Sensingen_US
dc.titleNumerical Reconstruction and Applications of Acoustic and Electromagnetic Ultra-Wideband Localized Pulses Generated by Dynamic Aperture Antennasen_US
dc.typeDissertationen_US
dc.contributor.departmentElectrical and Computer Engineeringen_US
dc.description.degreePh. D.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineElectrical and Computer Engineeringen_US
dc.contributor.committeechairBesieris, Ioannis M.en_US
dc.contributor.committeememberShaarawi, Amr M.en_US
dc.contributor.committeememberScales, Wayne A.en_US
dc.contributor.committeememberKohler, Werner E.en_US
dc.contributor.committeememberElshabini-Riad, Aicha A.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-02898-04748/en_US
dc.date.sdate1997-12-17en_US
dc.date.rdate1998-01-30
dc.date.adate1998-01-30en_US


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