A Low Profile Ultra-Wideband Antenna Design with Reconfigurable Notch-Bands for Wideband and Narrowband Applications

A novel low profile ultra-wideband antenna design has been presented in this work, that offers switchable band-notch characteristics suitable for both wideband and narrowband applications. The ultra-wideband characteristics (3.1–10.6 GHz) have been accomplished by using a unique elliptical shaped radiating structure, which is fed by a 50 Ω rectangular feedline and incorporating a defected ground structure that encompasses a pair of L-shaped slots and two rectangular slots for enhancing impedance matching performance. The proposed design has offered four notch-bands (Wi-Max, WLAN, X-band and C-band) that have been attained by using combinations of various types of slot structures in distinct parts of the proposed design along with a pair of split ring resonators. The reconfigurability among the desired notch-bands have been realized by configuring five switches in their ON/OFF states, which has resulted in a design apt for various narrowband applications. Antenna design optimization and performance evaluation has been carried out with the help of HFSSv13 tool. The performance of antenna has been assessed in terms of VSWR, gain and radiation patterns. The simulated and measured results have validated that antenna exhibits an operational UWB bandwidth from 3.1 to 10.6 GHz (with VSRW < 2) encompassing four notch-bands at 3.1–3.65 GHz (Wi-Max), 4.9–5.56 GHz (WLAN), 5.9–6.4 GHz (C-UPLINK) and 7.3–8.5 GHz (X-UPLINK). The profile size of the presented antenna (24 × 24 × 1.6 mm3) is appreciably compact and displays a fairly stable gain and radiation pattern characteristics for complete operational bandwidth except for four switchable notch-bands, making it suitable for wideband and narrowband applications.