Double-Elliptical Micro-Strip Patch Antenna for Higher Design Flexibility and Miniaturization

Abstract

Micro-Strip Patch Antenna (MSPA) finds large scale applications in various fields of communication. Elliptical shaped patch antenna is a prominent category among MSPAs. Possibility of circular polarization and dual resonant frequencies makes the Elliptical Micro-strip Patch Antenna (EMPA) widely accepted in modern communication devices. The present work aims to identify the constraints in further advancements in the design of EMPA and propose a novel shape to overcome these constraints. Minimizing the patch area and increasing the number of degrees of freedom in design were found to be the challenges. To overcome these challenges, a newly shaped patch called ‘Double-Elliptical Patch (DEP)’ is proposed for designing ‘Double-Elliptical Micro-strip Patch Antenna (DEMPA)’. A double-ellipse is a combination of two half-ellipses either with the same minor axis and different semi-major axes or with the same major axis and different semi-minor axes. The DEP has an additional degree of freedom in design compared to elliptical patch, which leads to greater design flexibility. In the present work, a DEP with the same horizontal major axis and centrally given feed was designed using Ansoft HFSS software. The semi-minor axis of upper half-ellipse was varied by keeping the semi-minor axis of lower half-ellipse a constant. The radiation properties of DEMPA were found to be similar to that of corresponding EMPA and this was achieved with less patch area. The maximum percentage reduction in patch area was 10.714%. The DEMPA covered the entire frequency range of Ultra Wide Band (UWB).