Control of the impedance bandwidth of wideband planar monopole antennas using a beveling technique

Abstract

Wideband planar monopole antennas have recently been proposed for use on digital mobile terminals. The square planar monopole is the simplest to analyze, and suffers little degradation of radiation pattern within the impedance bandwidth. The addition of a bevel on one or both sides of the feed probe is shown to increase the bandwidth with good control of the upper edge frequency. The impedance bandwidth ratio for this antenna is shown to vary from 2:1 to 6:1, which can be controlled by beveling the planar geometry.