Performances of ultra-wideband disc monopoles in time domain

A study on the time-domain characteristics of two ultra-wideband disc monopole antennas with different feeding structures have been presented. First, the transfer functions and group delays of the two antenna systems are obtained in the measurements. Then their respective impulse responses are investigated through a convolution approach. It is shown that by properly selecting the input source signal the spectrum of the transmitted signal can meet the Federal Communication Commission-defined emission mask. It is also demonstrated that the received signal waveforms generally follow the shape of source pulse with slight distortion and ringing.