Compact Modified Elliptical-Shaped Ultra-wideband Filtering Antenna with Improved Band-Edge Selectivity.

A compact filtering antenna with higher selectivity near band-edge frequencies for ultra-wideband (UWB) applications is presented and developed in this article. The antenna with filtering characteristics is formulated by integrating a rectangular-impedance resonator-based bandpass filter into the feedline of a modified elliptical-shaped monopole radiator. Initially, a modified elliptical-shaped monopole radiator is designed and numerically simulated to ensure the overall performance over the UWB band. The modified elliptical shape is used as a radiator to increase the electrical length while maintaining minimum physical size. The size of the UWB antenna is merely 0.518<italic>λ</italic>AL × 0.272 <italic>λ</italic>AL (where <italic>λAL</italic> is the guided wavelength at 2.62 GHz). Furthermore, to enhance the performance characteristics of the filtering antenna along with band-edge selectivity, geometrical parameters are optimized using a numerical simulation tool. It exhibits a simulated impedance bandwidth of 112% (3.05–10.81 GHz) with an electrical size of 0.676<italic>λ</italic>FL × 0.316<italic>λ</italic>FL (where <italic>λFL</italic> is the guided wavelength at 3.05 GHz). The experimental results of the fabricated UWB antenna and filtering antenna prototypes agree well with their simulated results. [ABSTRACT FROM AUTHOR]