Development of inductive-loaded ultra-wideband monopole antennas from stepped-impedance resonators

摘要

An ultra-wideband (UWB) printed monopole antenna is designed from stepped-impedance resonator (SIR) geometry. An inductor which is loaded in series between the radiating strips combines the multiple resonance bands of a two-strip stepped-impedance printed monopole antenna into a single ultra-wide resonance band. The two-strip inductive-loaded stepped-impedance printed monopole antenna is theoretically analysed for its resonant frequencies with the proposed modified transmission line analysis of inductive-loaded SIR model. The proposed analysis is validated by comparing the resonances with the electromagnetic simulation results and real-time measured results from the fabricated prototype of the antenna. The prototype of the two-strip inductive-loaded stepped-impedance printed monopole antenna fabricated on the low-cost FR4 substrate, resonated for the ultra-wide frequency range from 2.58 to 10 GHz.