Performance enhancement of duplex antenna for wireless communication

A compact and integrated duplex antenna has been designed. The duplex action is made possible by integrating the duplexer and a rectangular dual band patch antenna. A couple of sets of split ring resonators are used for filtering while a stub loaded resonator serve as the junction resonator. A slot in the ground is provided to achieve coupling between the rectangular patch antenna and the hairpin resonator. Further, to make this design compact, the 50 ohms interface and the matching networks between them are eliminated. This proposed duplex antenna provides two frequency channels of 2.41–2.47 GHz for transmitting and 2.71–2.78 GHz for receiving. It provides better isolation and is compact as compared to other designs in the literature. The simulated results indicate that the isolation for both transmitting and receiving bands is 52.5 dB.