Numerical Simulations of Ultrawide Band TEM Antennas

This paper numerically studies the radiation processes of the ultrawide band electromagnetic pulse emitted from the TEM antenna fed through the coaxial transmission line. The front end of the TEM horn antenna is a parallel-plate transmission line. The finite-difference time-domain method is adopted to simulate the processes of transmission in the parallel-plate transmission line and TEM horn. For the TEM horn, this paper presents the input impedance and voltage standing wave ratio as a function of frequencies. The radiated field distribution and energy pattern are also provided.