Investigation on Miniature Wideband Patch Antenna for Portable Wireless and Cellular Applications

A low-profile miniature antenna with very wide bandwidth is proposed for emerging multimode devices. It comprises a small circular patch antenna loaded by a metallic annular-ring and located on a laminate with a slotted ground plane. The design achieves a very compact low-profile antenna with broadband performance. By optimizing the parameters of the annular-ring patch antenna, very broadband characteristics can be obtained. The measured results show that the antenna achieves a 10 dB return loss from 1.383 GHz to 2.210 GHz, (827 MHz) ie about 47% with respect to the centre frequency 1.796 GHz. The measured results are in good agreement with the simulated results. The radiation patterns and gains are also presented. The working frequencies for the proposed antenna include the GPS frequency (1.575 GHz), DCS band (1.710 GHz-1.880 GHz), DECT, GSM1800 and the UMTS (1.920 GHz-2.170 GHz) band.