Application of Resonant Modal Theory to the Design of Dual-Band Wideband Dipole Antenna

This letter proposes a novel dual-band wideband dipole antenna with loaded folded stripes, which is designed in terms of the resonant modal theory (RMT). The proposed dipole with loaded folded stripes evolves from the typical dipole. The first five resonant modes of the dipoles with varying lengths of folded stripes are analyzed by the RMT, which clearly reveals the influences of the loaded folded stripes on the resonant frequencies of the proposed dipole. Finally, a voltage source is introduced at the center of the proposed dipole to excite the first, third, and fifth resonant modes, resulting in a dual-band wideband dipole antenna. The lower band of the simulated dipole antenna operates at the first resonant mode and achieves 14.4% fractional impedance bandwidth, while the higher band consists of the third and fifth resonant modes and achieves 29.0% fractional impedance bandwidth. The proposed dual-band wideband dipole antenna is fabricated and measured, showing good agreement with the simulated results.