Design of a wideband parallel-coupled filtering antenna based on dual-frequency matching condition

Abstract

In this paper, a wideband filtering antenna is designed based on the dual-frequency matching condition. Instead of matching at only one radiating frequency in the conventional filtering antenna design, an antenna element with two radiating frequencies are considered and equivalently modeled as two series-connected parallel RLC resonators, a series inductor, as well as a shunt capacitance. To obtain a wideband impedance matching, last two stages of the parallel coupled-line sections in a filter are synthesized for matching the antenna at two frequencies. Finally, a prototype of a four-pole filtering antenna is designed and fabricated. The measured results achieve a wide bandwidth of 27.8% over 2.12-2.81 GHz with a flat antenna gain of 3.41 dBi over all the filtering band.

Filtering wideband slot antenna using split-ring resonator

“…There is mutual coupling when the antenna cascades with filter, which could deteriorate the performance of antenna and filter. Nowadays, collaborative design methods of antenna and filter are becoming attractive, namely, filtering antenna [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. A dual-band filtering antenna is reported in [15].…”