Slot Antenna for Multi-Band Frequency Diversity

A slot antenna has been designed and optimized to obtain frequency reconfigurability over a wide range of frequencies. The proposed antenna has a rectangular slot with a hexagonal slot being placed in the inner conducting element. The antenna is fed through a 50Ω microstrip feed line placed on the other side of the substrate. The resonant frequency is controlled by changing the capacitance value of the varactor diode place between the two conducting elements providing a various range of resonance frequencies, frequency bands, and different bandwidths. The suggested slot antenna is simulated using the Ansys Electronics Desktop simulator (HFSS). The reflection coefficient shows the quad frequency bands cover (2.31 - 2.5), (2.9 - 3.27), (4.28 - 5.23), and (5.4 - 5.74) GHz. Other antenna parameters have been monitored to verify its performance such as gain, radiation efficiency, input impedance, and radiation patterns.