Performance enhancement of annular ring antenna using air gaps in stacked substrate

This Paper presents the analysis and design of an enhanced gain annular ring antenna operating at higher modes. To enhance the gain of the annular ring antenna several gain enhancement techniques like stacking and introducing air gaps are used. Annular ring antenna is excited at TM
₃₁
mode and exhibits maximum power at angles other than 0
⁰
. Theoretical, simulated and experimental results are in good agreement and show an increase in gain.