Design of planar monopole antenna in velvet shape having two gap sleeves

In this study, a wideband antenna was proposed by adding two strip sleeves with gaps according to a velvet shape in a planar monopole shape basically having the velvet structure. By adding two gap sleeves, additional resonance could be induced, thereby inducing impendence matching effectively. Through the antenna property analysis, it was confirmed that changes in the feed gap, sleeve length, and sleeve gap are important parameters of impedance matching. The total size of antenna substrate was 40 mm × 40 mm2, and FR4 dielectric substrate with 1 mm thickness was used. As a measurement result, the bandwidth of 10 dB was confirmed to be 12.09 GHz in the 2.91–15 GHz bands. In all frequencies, results similar to the radiation pattern of dipole antenna were shown. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:21–24, 2016