A compact ultra-wideband (UWB) square and circular slot ground plane planar antenna with a modified circular patch for UWB communication is presented. This antenna has a low reflection coefficient and high gain in the range of 8.94 GHz, starting from 2.85 to 11.79 GHz. The proposed antenna demonstrates UWB behavior with electrically small dimensions of 0.18 λ0×0.14 λ0×0.015 λ0 (λ0 is the free-space wavelength at 2.85 GHz). The fractional bandwidth of the antenna is 122.1%, with stable radiations. The antenna's maximum gain stands at 2.79 dBi, and the antenna's peak efficiency stands at 72%, respectively. It is lightweight, compact, and easy to manufacture. Hence, it can be used for the complete range of UWB applications and covers Wi-Max/WLAN/ X-Band and Ku-Band.
