In this paper, a fan-shaped ultra- wideband (UWB) microstrip patch antenna is re- ported. The antenna is designed, simulated, fab- ricated, and tested. The antenna operates over a 3.1 GHz – 6 GHz for Wireless Capsule Endoscopy (WCE) applications with VSWR less than 2 and return loss is lower than -10 dB. The antenna is a monopole circular structure with radius of 10.2 mm and ground plane dimension 24 x 16 mm (“Lg x Wg”) is designed on substrate FR4. The impedance matching and radiation characteristics of the designed structure are investigated. The pro- posed antenna with small size and different ground structure is considered to reduce the surface wave and to achieves high impedance bandwidth and good gain performance for ultra-wide band (UWB) range with specific absorption rate (SAR) 1.126 W/kg for 10 g of tissue.