This paper presents a simple structure and small size antenna design with dimensions of 43×47 mm 2 to perform an ultra-wideband (UWB) frequency range using semicircular co-planar waveguide (CPW). has been designed simulated by the computer simulation technology (CST) microwave studio suit. In this work, we (about GHz 10 GHz) feeding semi-circular compact via for input impedance 50 Ω. The CST re...