Study on Super-Wideband Planar Asymmetrical Dipole Antennas of Circular Shape

We present a detailed study of a very large band planar circular asymmetrical dipole antenna, fed by a microstrip, for the purpose of covering most of the common communication channels with one solution. The study has been performed on two planar substrates having different dielectric permittivities. The prototype on the substrate with lower permittivity shows much larger bandwidth, and it has been realized and fully characterized, in terms of impedance matching and radiation properties. Its measured band ratio is 21.9:1. The comparison with other super-wideband (SWB) antennas of similar type, with more complex design and therefore required optimization, shows that this prototype has very appealing features of very large absolute bandwidth and band ratio, and a compact size.