This paper presents the parameterization of the structure of a miniaturized exponential UWB TEM horn antenna and its effect on the matching impedance and directivity. In addition, a microstrip balun that feeds the antenna was proposed in order to improve the balance, and the return loss for low frequencies. Both the antenna and the microstrip balun were simulated to obtain a final high performance model to be manufactured at a later time. The proposed antenna operates in a frequency range from 3.2 GHz to 7.5 GHz, meeting the standards established by the FCC and the ETSI for ultra-wideband technology. Moreover, based on these characteristics, the antenna have many UWB radar applications such as monitoring of structures (buildings, bridges, e...