A Dielectric Resonator-Loaded Minkowski Fractal-Shaped Slot Loop Heptaband Antenna

A multiband fractal co-planar waveguide (CPW)-fed slot antenna loaded with a dielectric resonator conforming to multiple wireless standards is presented in this paper. The Minkowski fractal geometry is utilized to generate multiple frequency bands as well as to provide a miniaturized design compared to its Euclidean counterpart. The idea behind placing the dielectric load is to serve a dual purpose of enhancing the impedance bandwidth of the antenna at the upper frequency band as well as improving the overall gain of the antenna. The slot loop acts as a hybrid antenna performing the task of both an antenna as well as a feed mechanism for the dielectric slab to radiate. Design guidelines involving closed form formulae and equivalent model consisting of lumped resonators, distributed resonators and impedance transformers of the dielectric-loaded fractal slot antenna are provided to present an insight into the functioning of the antenna. The reflection coefficient parameters of the antenna yield a close match between the circuit model and those obtained from full wave simulator. The proposed antenna exhibits a heptaband performance with a maximum gain of 3.1 dBi.