This paper presents the enhancement of bandwidth in circular and annular ring sectoral patch antennas. The cavity model approach has been used in identifying the higher order mode resonances that are close to each other in the sectoral patches. Bandwidth enhancement centered around these higher order mode resonances is achieved through the use of either a shorting pin or a parasitic patch. The sectoral patches have been simulated using ANSYS HFSS. The optimum position of the shorting pin and the dimension and position of the parasitic patch were determined through parametric simulations on HFSS. Measurements showed that the annular ring sectoral patch with optimally positioned shorting pin achieved 6.3 percent bandwidth with a return loss performance greater than 10 dB while the circular sector patch with a parasitic patch achieved 5.6 percent.
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