Broadband slot cut S-shaped microstrip antenna

Bandwidth of compact S-shaped microstrip antenna has been increased by cutting S-shaped slot inside the patch. In this paper an analysis to study the broadband response in slot cut S-shape microstrip antenna is presented. The S-shaped slot in the patch tunes higher order TM
₂₀
mode frequency with respect to lower order TM
₁₀
mode, to realize bandwidth of more than 70 MHz (~9%). The S-shaped slot modifies the surface current distribution at TM
₂₀
mode that gives broadside radiation pattern over complete bandwidth with peak broadside antenna gain of nearly 7.5 dBi. In the reported literature an explanation for broadband response in slot cut compact antennas in terms of their operating modes is not given. The novelty of proposed work lies providing detail explanation for working of slot cut patch antenna in terms of its resonant modes.