Design of the monoblock duplexer for the application of cellular band repeater

In wireless communication the demand for handsets is increasing. A duplexer is the critical component of a handset for mobile communication, to separate the transmitting and receiving signals. Thus the need of the duplexer for a repeater is also increasing. In this paper the design of a duplexer for a repeater is presented. We present a transmission line Chebyshev filter which is referred to as a uniform impedance resonator (UIR). By using conventional filter theory, we extract the equivalent circuit. The paper presents a simple pattern that is easy for mapping one to one with circuit components. A duplexer for cellular band (824 - 849 MHz for tx band and 869 - 894 MHz for rx band) is designed and fabricated. The design procedure is presented and validated by simulation results and the performance of the fabricated duplexer