High data speeds and multiband operations of modern wireless communication systems have significantly increased the demand for simple, but very broadband antennas. In general, the systems need low-cost solutions with application-specific requirements in terms of impedance bandwidth, polarization and gain. Planar monopole and dipole antennas are often good options here - though they usually have a high profile above the ground-plane.
The UWB accordion monopole achieves a much wider impedance bandwidth than most other planar monopoles, including popular structures like the Circular disc monopole and the Rectangular monopole with a semicircular base. While an impedance bandwidth of up to 38:1 is reported (see graph image below), the uniformity of the azimuthal pattern is only retained for a 3.4:1 bandwidth as shown in pattern comparisons in the second image below. The exceptionally wideband operation of this structure also makes it a good candidate for ultra wideband pulse applications. ...Typical normalized reflection coeefficient of the UWB accordian monopole. Typical 3D Radiation patterns vs frequency.