Low-Profile Rolled Planar Antenna with Wide Bandwidth

A novel size-reduction technique for a planar monopole type antenna is presented. By rolling the planar element of this antenna, a low-profile radiator with broad impedance bandwidth is obtained without excessively perturbing its radiation properties. The proposed antenna is capable of covering frequencies in the range 3.1 GHz to 15 GHz. The antenna yields a high gain with high radiation efficiency across the full bandwidth. Radiation patterns show good omnidirectional features, so it is a remarkable candidate for in-door or vehicular applications where large frequency range is required.