INVESTIGATIONS ON SOME MULTIFREQUENCY DIELECTRIC RESONATOR ANTENNAS (DRAs)

Abstract

Firstly, a dual band Dielectric Resonator antenna with uniform dielectric substrates slacked together over one another to Jhrmn a large piece of Dielectric material of required dimensions by using only a single port was designed. This designed antenna was of linear polarization. The higher order mode was used to design the dual band dielectric resonator antenna by using only one feed. The dielectric ,nate,'ial was Jbrmecl by stacking unffbrmn Dielectric substrate materials of high permittivity one over the 01/ic,' by using a thin transparent/jim of/ow permiuivity and ultrathin thickness. r Secondly, a dual band Dielectric Resonator antenna was designed with non-uniform dielectric substrates of diflreni periniltivity by using similar single port as in first case. This antenna was also of linear polarization. The higher order mode techniques were used in this design of dual band dielectric resonator antenna by using only a single feed. In this the Dielectric material was mizade by stacking the non-unifhrmn Dielectric substrate materials of diffirent permittivity by using a thin transparent fl/in of low penn ittivity and ultrathin thickness.. Finally, a Multfrequency Dielectric Resonator Antenna is designed by in ultiple slots which are etched on the upper groundplane of the substrate. The total number of feedings are two and are orthogonal to each other. In particular Dielectric Resonators of two d?fferent permittivities and dimensions are used. The two slots etched on the substrate are designed in such a way that they are also orthogonal to each other. Late,' the slot and the Dielectric material which is placed on the substrate are trimmed in one of the two opposite corners in one JCeding to get the desired resonant frequencies with polarization in one direction where the direction depends on the trimmed slots. The other two corners of the slot and dielectric are trimmed on the secondfeeding to attain slightly opposite polarization. The antenna parameters have been opiinzized using CST Microwave Studio and a substrate of thickness 1.5748 mm and relative permiuivity of 2.5 has been used fbr simulation as well as Jbr the /ahrication of antennas