A Novel Coplanar Waveguide Feed Zeroth-Order Resonant Antenna With Resonant Ring

A novel structure of a coplanar waveguide (CPW)-fed antenna is presented. A method to extend the bandwidth of metamaterial (MTM) antennas based on composite right/left-handed transmission line (CRLH-TL) is proposed. A prototype of the proposed antenna has been constructed and experimentally studied. The measured return loss bandwidth (-10 dB) is enhanced from 240 MHz (1.63-1.87 GHz) to 840 MHz (1.67-2.51 GHz), which corresponds to the fractional bandwidth of 14.0% and 40.2%. Measured peak gain and measured radiation efficiency are up to 4.13 dB and 83.69% at the operating frequency of 2.09 GHz. Because of wide bandwidth, good radiation characteristics, and acceptable peak realized gains, the proposed antenna is very suitable for GSM/UMTS/LTE/WLAN wireless communication systems.