Ultra-Wideband Antenna Modeling and Design
Variations on ultra-wideband (UWB) systems have been around for a long time. Early on we might consider radar to be an early form of UWB, though far narrower in bandwidth than current systems. Radars are often found to have about a 1 s pulse length, giving a bandwidth of about 1MHz and a radar distance resolution of about 500m. The introduction of nuclear weapons brought a whole new age of pulse analysis related to the electromagnetic radiation created by a nuclear blast. A very similar phenomenon is the pulsed energy created by a lightning strike. Both of these events have a source that is often modeled as a double exponential and brought in a new era of antenna analysis for transient events. A major contribution was the observation that most antennas and scattering structures had a transient response that could be modeled by a resonant-pole series. A theoretical basis was developed by Baum (1971) that demonstrated the poles were a function of the object only and the directional information was all contained in the pole amplitudes or residues. This paper connects this transient history and that of classic frequency domain antenna concepts with the needs of UWB.
Please disable any pop-up blockers for proper viewing of this Whitepaper.