Simulation and experimental research on the multi-band slot-loaded printed antenna

Slots which are parallel with the bottom side are loaded at the two equilateral sides of the monopole isosceles triangle printed antenna to achieve multi-band in the operating frequency. The antenna is simulated by CST MICROWAVE STUDIO®, a 3-dimentional full wave electromagnetic simulation software, the simulated results indicate that the central frequency of the pass-band, as well as the bandwidth and the number of the pass-band can be controlled by the slots´ length and width, loading position and the number of the slots. The resonant frequencies have certain relation with parameters of the antenna structure, and the interaction between pass-bands is week. A monopole multi-band antenna synchronously operating in three pass-bands, 2.4/3.5/5.5 GHz, is designed and fed by coplanar waveguide. The simulated results also show that the antenna has omnidirectional radiation in H plane. Based on the simulation, prototype of the antenna is manufactured and measured. Finally, the measured results well match the simulated, which verify the design idea is feasible. The antenna size is just 27.74% of the corresponding wavelength of the first resonant frequency, and this compact antenna can be applied in WLAN and WiMAX systems.