Design and analysis of compact and multi-band circular antennas

This paper discusses the design, analysis and optimization of highly compact, multi-band and low profile patch antenna on a 0.5 mm thickFR-4 substrate (ε_r=4.4). The need for compact and multi-band antennas is the key in the realization of portable electronics, like smart phones, iPads and laptops. In this paper a slotted, circular patch antenna is presented which operates, giving a dipole like radiation pattern, in the 1-7 GHz frequency range, including the Industrial Scientific and Medical (ISM) and Worldwide interoperability of Microwave access (WiMax) bands, giving improved return loss (<;-20 dB). The antennas far-fields and performance parameters (gain, directivity, and efficiency) are evaluated by solving the Maxwell´s equations using a numerical Finite Integration Technique (FIT), incorporated in CST MWS.