In this article, the slotted microstrip‐ fed elliptical patch antenna is designed and optimized to operate at the resonance frequency of 5.38 GHz. Then, the designed patch antenna is further analyzed in a resonant cavity formed by a frequency selective surface (FSS) superstrate and antenna ground plane. The highly reflective behavior of FSS from the offset of the resonance is utilized for improving the performance of the antenna. The optimized slotted geometry produces a gain improvement of 2.5 dBi, impedance bandwidth improvement of 0.21 GHz, simultaneously at the operating resonance frequency of 5.38 GHz. After placing an FSS superstrate at a height of 28.5 mm above the antenna substrate, further improvement of 5.1 dBi gain and 0.13 GHz bandwidth is attained, For validation purpose, the prototypes of the slotted patch antenna with and without FSS superstrate are fabricated and characterized. A fairly good agreement is achieved in the measured and simulated results.