Compact and Efficient Printed Monopole Antenna with Broadband Circular Polarization

Abstract

This research article features about improvised, compact and efficient circularly polarized printed monopole antenna with broadband circular polarization for applications in the frequency from 1 GHz-to-7 GHz. Initially, a $\boldsymbol{\lambda}/4$ circular-shaped linearly polarized monopole antenna with the partial ground plane of $75\ \mathbf{mm}\times 100\ \mathbf{mm}$ (Antenna-1) is designed. For getting circular polarization, partial ground plane is converted into an asymmetrical staircase structure, due to which, there is presence of horizontal and vertical field components (Antenna-2). A PEC reflector of $75\ \mathbf{mm}\times 100\ \mathbf{mm}$ is placed above the patch at a height of 55 mm (Antenna-3) for improving antenna parameters. It exhibits impedance bandwidth of 4.9 GHz (1.87-6.77 GHz), axial bandwidth of 1.41 GHz (4.08-5.49 GHz) and average realized gain ≥ 5.5 dBc with antenna efficiency ≥ 78% over the frequency bands. These corresponding results are the improved version of antenna-2 (axial bandwidth of 720 MHz and realized gain ≥ 4.6 dBc is observed). A detailed state-of-art is presented and it is inferred from the above results that, it can play a vital role for modern day's applications in wireless communication domain.