Abstract: This paper presents a study of a printed half circular with stepped triangular monopole antenna for UWB systems. Printed on a dielectric substrate and fed by a 50 ? microstrip line, the proposed antenna shows satisfactory radiation characteristics within the operating bandwidth of 9.7 GHz in the range of 2.8 GHz to 12.5 GHz for a return loss (S11) of less than -10 dB. Compared to the rectangular stepped configuration, the proposed antenna has larger bandwidth and better impedance matching. The designed antenna gives gain in the range of 2.8 dB to 5.3 dB over the bandwidth.

Keywords: Circular patch antenna, ultrawide band (UWB) antenna, microstrip feed line, partial ground plane.