This paper presents modeling of annular patch antenna. The S and Z parameters of an Annular patch Microstrip antenna are investigated and optimization. The optimization is performed by varying the inner and outer radius of annular Ring. The impedance and radiation characteristics of annular patch antenna are examined and compared. It is able to achieve a return loss less than -36 dB and VSWR < 2.

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Return loss annular patch Impedance Microstrip antenna resonant frequency dielectric material VSWR patch radius