Novel compact wideband or multi-band planar monopole antenna

With the development of 3/sup rd/ generation wireless communication systems (UMTS), future mobile wireless devices are required to operate at multiple frequencies. Although there are currently a number of dual-band antennas available, these antennas suffer from certain performance limitations (e.g. gain, bandwidth and case of construction). In this paper, a compact wideband antenna capable of meeting some of the system requirements of existing and future 3/sup rd/ generation systems are demonstrated. The structure of this antenna is based on the planar monopole antenna. When a shorting pin is incorporated into the antenna structure, an additional mode in excited below the fundamental mode. The size reduction achievable for this antenna is approximately 50% compared to an equivalent planar monopole without a shorting pin. In addition to its wideband performance, this antenna can also be reconfigured for dual band operation.