A Wideband Filtering Antenna Excited by Independent Triple-Mode Resonator

A compact filtering antenna with wide-band filtering performance is proposed. Triple-mode resonator and L-shaped monopole antenna are integrated to be an antenna. The L-shaped monopole antenna is considered as a radiating impedance, and its equivalent circuit is the last resonator of a bandpass filter. The matching between the resonator and the antenna can be achieved by adjusting the width of coupling gap. Finally, a filtering antenna operating at 3.45 GHz is designed, and the fractional bandwidth of 12.7% is achieved. Experimental results show that it has a good frequency selectivity as a bandpass filter, and good radiation pattern as an antenna.