SAW ANTENNA DUPLEXERS FOR MOBILE COMMUNICATION

Abstract

Mobile communications systems such as cellular radios have recently become very widespread and important to both business and personal users. A key component in the radio transceiver is an antenna duplexer, which makes it possible to use a single antenna to transmit and receive RF signals simultaneously. In this chapter, block diagrams of radio transceivers are shown and the frequency characteristics required for duplexers are discussed with regard to the system requirements. Procedures for designing duplexers using SAW-resonator-coupled filters and experimental results relevant to several systems are presented. Non-linear characteristics of the duplexers are also discussed.