Spherical Fidelity Patterns of UWB Antennas

The time domain radiation properties of UWB antennas are analyzed, especially the angular dependent impulse distortion, with respect to the signal transmitted in the main beam direction, is investigated. The correlation properties of the radiated pulses are determined by the so called fidelity F. The fidelity F is together with the peak pulse amplitude P a powerful tool for the characterization of impulse radiating antennas. The results are applied to two different UWB antennas, a Vivaldi antenna and a Bow-tie antenna. The spatial regions with good correlation and high peak power are determined for both by measurements for verification. The results are vital for UWB impulse communications, and for UWB Radar as well.