Ultrawideband antenna distortion analysis based on Prolate Spheroidal spectral decomposition

Antenna waveform distortion evaluation in Ultrawideband (UWB) communications has become an important concern due to the possible degradation in system performance. Fidelity is the typical measure to take into account distortion for single waveforms. In this paper, a new method designed for evaluating distortion in multiple waveform sets is proposed, exploting two important mathematical concepts: orthogonality and Parseval’s theorem. The method is based in a spectral decomposition obtained using Prolate-Spheroidal Wave signal spaces and an evaluation of the energy which lies in those spectral modes. It is showed that this measure allows to evaluate distortion based in an energy approach. Finally, this measure is applied in three real links using computed transfer functions when two typical radiating structures are used to build a radio link.