A Conformal Band-Notched Ultrawideband Antenna With Monopole-Like Radiation Characteristics

A conformal, planar, and low-profile ultrawideband antenna with monopole-like radiation and band-notched characteristics is presented. A circular patch shorted to the ground is combined with two rectangular slots and two concentric rings, to achieve an ultrawide bandwidth from 3.8 to 8.3 GHz with a single rejection band from 5 to 6 GHz. The monopole-like radiation features, generated by combining TM01 and TM02 operating modes of a circular patch antenna, are maintained over the entire operating bandwidth. The antenna has only 0.046 lambda(o) height at 3.8 GHz and is realized using polydimethylsiloxane conductive fabric composite technology making it highly flexible and physically robust. This was validated through severe bending tests with various curvatures.