Nian Sum, Katherine S. Ziemer
Date of Award
Doctor of Philosophy
Department or Academic Unit
College of Engineering. Department of Electrical and Computer Engineering.
Electrical engineering, Ferrite
Telecommunication systems--Technological innovations
Indium doped BaFe12-xInxO19 was prepared by a modified ceramic technique using In2O3, BaCO3, and Fe2O3 followed by mechanical dispersion. The amount of Indium x was controlled by x = 1.0, 1.5 and 2.0. The powder was screen printed on alumina substrate using a suitable binder and in-plane oriented under a dc magnetic field of 15 kOe. The screen printed films were annealed at different durations to produce dense and thick ferrite materials. Scandium doped BaFe12-xScxO19 were produced by a modified chemical co-precipitation technique. The amount x of Scandium doping was varied by x=0.3, 0.5, 0.8 and 1.0. The size of platelets of BaFe12-xScxO19 was controlled by sintering temperature and time. The screen printed and in-plane oriented films were annealed at different temperatures to produce a dense and thick ferrite films. To meet the industry requirements in telecommunication systems, a new type of ferrite phase shifters should be able to work at Ka-band and higher frequencies. Barium hexaferrite with high anisotropy field (HA) is the candidate for high frequency ferrite phase shifter and we could control HA by doping Scandium and Indium. We designed and fabricated a prototype of microstrip line phase shifter by using BaFe10.5In1.5O19 and it worked at 33 GHz. We compared the data of phase shift with simulation.
Sakai, Tomokazu, "Toward the development of self-biased ferrite microwave devices" (2008). Electrical Engineering Dissertations. Paper 20. http://hdl.handle.net/2047/d1001861x
Click button above to open, or right-click to save.