Norman window slot antenna with sectoral feed backed by linear phase reflector for ultra wideband applications

Abstract

An ultra wideband (UWB) slot antenna is proposed, developed, and experimentally validated in this article. The Norman window-shaped UWB slot antenna demonstrates stable radiation characteristics in both directions—zenith (θ = 0°) and nadir (θ = 180°) over the entire UWB frequency range (3.1–10.6 GHz) as observed in both simulations and experiments. A linear phase reflecting UWB frequency selective surface (FSS) is proposed by printing two orthogonal layers of pair of double rectangular loops on the same side of dielectric substrate as a merged frequency selective surface (MFSS). The UWB MFSS is then loaded with the slot antenna and the impact of MFSS on the impedance and radiation characteristics in different configurations of antenna and MFSS together is studied. One configuration with optimum solution is developed for experimental validations followed by the analysis of its radiation characteristics. The proposed antenna demonstrates a directional radiation pattern due to suppression of back lobe radiation when integrated with the UWB MFSS. The proposed antenna demonstrates maximum gain of 7.86 dB with a gain enhancement of 3.6 dB in boresight (θ = 0°) direction when MFSS is applied as a reflector to opposite side of the antenna slot.