A novel ultra-wideband knife-shape TEM horn antenna design for transient application

As is well known, more pulse energy is distributed in the relatively low frequency range than that in the high frequency range for a short pulse excitation. However, it´s difficult to obtain a well low-frequency performance for the relatively limited spatial volume of antenna. Besides, the conventional knife-shape TEM horn antenna introduces some fluctuations in the main lobe radiation pattern over the center frequencies. In this paper, a new method is proposed to improve the aforementioned defects. A novel ultra-wideband(UWB) knife-shape TEM horn antenna is designed, which has simple construction, relatively small size and perfect performance for transient application. The simulation results show that the improved knife-shape TEM horn antenna structure exhibits low VSWR as well as good radiation pattern over 120 MHz -1250 MHz frequency band.