A compact simple structured filtering antenna utilizing filter synthesis technique

A compact simple structured filtering antenna and its synthesis method are presented in this paper. The filtering antenna is composed of an inverted-L antenna and a quarter-wavelength transmission line which are modeled by a series RLC resonator and a shunt LC resonator, respectively. Thus, the overall filtering antenna is modeled by the prototype bandpass filter. The detail synthesis procedures are introduced. The filtering antenna is printed on one side of the FR4 substrate that structure is extremely simple. The filtering antenna is designed at 2.45 GHz with 20% bandwidth. The far-field antenna gain is omnidirectional on its H-plane, and it maintains the averaged value around 1 dBi within the passband. The measurement results show good agreement with the simulations.