Application of Transmission-Line Model to Dual-Band Stepped Monopole Antenna Designing

This letter presents a novel approach for designing a dual-band planar antenna with only a stepped monopole. Transmission line theory and the resonator model are adopted to analyze the operating frequencies of the proposed antenna. A suspended stripline resonator is applied to emulate the radiation patches of the antenna. A design curve is established and used to develop a single-monopole antenna with dual operating frequencies. A closed form to design the antenna is derived under a specific condition. The proposed approach facilitates the design of the antenna without the time-consuming tuning of parameters and repeated electromagnetic (EM) simulation. Satisfactory agreement between the simulation results and the measurements validates the proposed design approach.