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Modern communication systems are evolving very quickly and tunable Radio Frequency (RF) components are needed to utilize the spectrum more effectively. Recent developments in small size and tunable microwave/RF components are attractive for communication and radar applications for industrial, civilian, and military purposes. Different frequency tuning methods of electrical, mechanical, optical, acoustic, and magnetic are employed for dual frequency of operation. New manufacturing methods are being continuously improved with great interest in additive manufacturing. This PhD thesis work focuses on design and frequency tuning of passive RF circuits using magnetic flux control of ferroic nanomaterials fabricated using additive manufacturing. In particular, the focus of the thesis is using nanoparticles of ferromagnetic Iron-Cobalt (Fe60Co40) and Cobalt ferrites (CoFe2O4) considered for their electromagnetic properties. Compared to ferroelectric materials, the tuning control circuit of ferro/ferrimagnetic materials can be designed without adding parasitic effects. The extracted electromagnetic properties of the realized composites are refraction index of nFeCo=4 and nCoFeO=2, magnetization saturation of MFeCo=198 emu/g and MCoFeO=46.8 emu/g, loss tangents of tanδFeCo |
