Wide-Beamwidth Broadband Antenna Using S-Shaped Dipole And Microstrip Antenna

Abstract

Bandwidth of compact S-shaped Microstrip antenna has been increased by cutting S-shaped
slot inside the patch. This paper presents a novel circularly polarized (CP) printed antenna
with wide bandwidth and wide axial ratio (AR) beam width and the study of broadband
response in slot cut S-shape Microstrip antenna. The wide beam width antenna is realized by
bending a linearly polarized dipole into “S” shape with variable line width, which achieves
circularly polarized radiation. It is found that this “S” antenna has some similar features to
the linear polarized dipole, such as the feeding method, the radiation pattern in some main
planes and nearly omnidirectional radiation in one main plane. The S-shaped slot modifies
the surface current distribution at TM20 mode that gives broadside radiation pattern over
complete bandwidth with peak broadside antenna gain of nearly 7.5 dBi.