The demand for high bandwidth and high directionality in modern communication system antennas has been increasing. In this study, two-layer microstrip patch, powered by cross slot and coupled microstrip lines, is utilized to make the bandwidth. Furthermore, the result of different steps on antenna bandwidth is examined. The antenna parameters were modeled and optimized using HFSS electromagnetic modeling software. Finally, it is confirmed that the upper sticker has a 4D trapezoidal structure and lower sticker has a 6D trapezoidal structure. It is concluded that S₁₁ antenna is less than -10 dB in the range of 7.2-12.6 GHz （54% of the relative bandwidth）.