New SAW antenna duplexers for single- and dual-band handy phones used in 800-MHz and 1.8-GHz cellular-radio systems

New SAW antenna duplexers used in EGSM/PCN dual-band handy phones have been developed. The differences between the single- and dual-band RF-circuit configurations are taken into considerations. Direct-parallel connection between the receiver SAW filter and the transmitter diode switch makes it possible to reduce the number of circuit elements and to achieve a small module size. The required frequency characteristics were also achieved.

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