Theory and Design of Tunable and Reconfigurable Microwave Passive Components on Partially Magnetized Ferrite Substrate

Handle URI:
http://hdl.handle.net/10754/621876
Title:
Theory and Design of Tunable and Reconfigurable Microwave Passive Components on Partially Magnetized Ferrite Substrate
Authors:
Ghaffar, Farhan A. ( 0000-0002-4996-6290 )
Abstract:
Typical microwave components such as antennas are large in size and occupy considerable space. Since multiple standards are utilized in modern day systems and thus multiple antennas are required, it is best if a single component can be reconfigured or tuned to various bands. Similarly phase shifters to provide beam scanning and polarization reconfigurable antennas are important for modern day congested wireless systems. Tunability of antennas or phase shifting between antenna elements has been demonstrated using various techniques which include magnetically tunable components on ferrite based substrates. Although this method has shown promising results it also has several issues due to the use of large external electromagnets and operation in the magnetically saturated state. These issues include the device being bulky, inefficient, non-integrable and expensive. In this thesis, we have tried to resolve the above mentioned issues of large size and large power requirement by replacing the large electromagnets with embedded bias windings and also by operating the ferrites in the partially magnetized state. New theoretical models and simulation methodology have been used to evaluate the performance of the microwave passive components in the partially magnetized state. A multilayer ferrite Low Temperature Cofired Ceramic (LTCC) tape system has been used to verify the performance experimentally. There exists a good agreement between the theoretical, simulation and measurement results. Tunable antennas with tuning range of almost 10 % and phase shifter with an FoM of 83.2/dB have been demonstrated in this work, however the major contribution is that this has been achieved with bias fields that are 90 % less than the typically reported values in the literature. Finally, polarization reconfigurability has also been demonstrated for a circular patch antenna using a low cost additive manufacturing technique. The results are promising and indicate that highly integrated ferrite based tunable components are feasible in small form factor, without the need of the large electromagnets and coils, and thus can be operated at very low bias levels as compared to the ones which are operated in the saturated state with external bias mechanisms.
Advisors:
Shamim, Atif ( 0000-0002-4207-4740 )
Committee Member:
Bagci, Hakan ( 0000-0003-3867-5786 ) ; Wu, Ying ( 0000-0002-7919-1107 ) ; Swaminathan, Madhavan
KAUST Department:
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Program:
Electrical Engineering
Issue Date:
Nov-2016
Type:
Dissertation
Appears in Collections:
Dissertations

Full metadata record

DC FieldValue Language
dc.contributor.advisorShamim, Atifen
dc.contributor.authorGhaffar, Farhan A.en
dc.date.accessioned2016-11-24T11:47:07Z-
dc.date.available2016-11-24T11:47:07Z-
dc.date.issued2016-11-
dc.identifier.urihttp://hdl.handle.net/10754/621876-
dc.description.abstractTypical microwave components such as antennas are large in size and occupy considerable space. Since multiple standards are utilized in modern day systems and thus multiple antennas are required, it is best if a single component can be reconfigured or tuned to various bands. Similarly phase shifters to provide beam scanning and polarization reconfigurable antennas are important for modern day congested wireless systems. Tunability of antennas or phase shifting between antenna elements has been demonstrated using various techniques which include magnetically tunable components on ferrite based substrates. Although this method has shown promising results it also has several issues due to the use of large external electromagnets and operation in the magnetically saturated state. These issues include the device being bulky, inefficient, non-integrable and expensive. In this thesis, we have tried to resolve the above mentioned issues of large size and large power requirement by replacing the large electromagnets with embedded bias windings and also by operating the ferrites in the partially magnetized state. New theoretical models and simulation methodology have been used to evaluate the performance of the microwave passive components in the partially magnetized state. A multilayer ferrite Low Temperature Cofired Ceramic (LTCC) tape system has been used to verify the performance experimentally. There exists a good agreement between the theoretical, simulation and measurement results. Tunable antennas with tuning range of almost 10 % and phase shifter with an FoM of 83.2/dB have been demonstrated in this work, however the major contribution is that this has been achieved with bias fields that are 90 % less than the typically reported values in the literature. Finally, polarization reconfigurability has also been demonstrated for a circular patch antenna using a low cost additive manufacturing technique. The results are promising and indicate that highly integrated ferrite based tunable components are feasible in small form factor, without the need of the large electromagnets and coils, and thus can be operated at very low bias levels as compared to the ones which are operated in the saturated state with external bias mechanisms.en
dc.language.isoenen
dc.subjectFerrite LTCCen
dc.subjectTunableen
dc.subjectReconfigurableen
dc.subjectMicrowave componentsen
dc.subjectPartially magnetizeden
dc.titleTheory and Design of Tunable and Reconfigurable Microwave Passive Components on Partially Magnetized Ferrite Substrateen
dc.typeDissertationen
dc.contributor.departmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberBagci, Hakanen
dc.contributor.committeememberWu, Yingen
dc.contributor.committeememberSwaminathan, Madhavanen
thesis.degree.disciplineElectrical Engineeringen
thesis.degree.nameDoctor of Philosophyen
dc.person.id102029en
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