Cross-finned UWB monopole for wireless applications: Design insight and characterization

Abstract

A simple yet novel cross-finned geometry of a monopole has been explored to realize a strong contender in the family of ultra-wideband antennas. This promises a consistent monopole like radiation over an ultra-wide impedance bandwidth (127%) with improved radiation characteristics. An extensive study supported by experiments has resulted in a reliable design guideline with a strong physical insight. A cross-finned top loaded structure having individual fin length (L) 11 mm and width (W) 5 mm and fin thickness (t) 0.7 mm, fed by probe pin of height h = 2 mm, is fitted to a circular ground plane of radius (Ga) 15 mm. It has been experimentally demonstrated to operate from 5 to 22.5 GHz with as much as 1–7 dBi peak gain and over the band high co-to cross polarization isolation (26–31 dB). The design is found to exhibit desired transmission and reception characteristics in time domain and is extendable up to 32 GHz to the upper side and 1.5 GHz to the lower side of the microwave band. This commercially viable design should find potential applications in compact and miniaturized wireless transceiver systems.