Open AccessNear‐field time‐domain characterisation of wideband antennas
Author(s) -
Mobashsher A.T.,
Abbosh A.M.
Publication year - 2015
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2015.2763
Subject(s) - wideband , directional antenna , omnidirectional antenna , time domain , near and far field , transient response , reflective array antenna , antenna (radio) , microwave imaging , slot antenna , physics , acoustics , electronic engineering , computer science , optics , microwave , telecommunications , engineering , electrical engineering , computer vision
Time‐domain characterisation is vital in verifying the suitability of wideband antennas for near‐field applications such as microwave medical imaging and sensing. To that end, a near‐field time‐domain characterisation method to calculate the near‐field transient response and the distortion of wideband antennas is proposed. The method uses a pulse merit factor, which consists of the near‐field time‐domain signal amplitude and a fidelity factor, both normalised to the highest values attained from the antennas. To verify the method, the transient responses of unidirectional and omnidirectional antennas designed for near‐field imaging are analysed. The analyses show that even though the investigated antennas cover the same band with the same average far‐field gain along the boresight direction, the unidirectional antenna exhibits 35% more pulse merit factor with less impulse distortion along the intended direction, which suggests better suitability for wideband near‐field imaging systems.