To provide an antenna common-use unit which has stable electric power resistance, even with respect to the input of a signal from an antenna terminal side and also has stable characteristics.
This unit is equipped with a transmission-side filter which has it input side connected to an input terminal, a phase shift circuit connected to this transmission-side filter, a reception-side filter connected to the phase shift circuit, an output terminal connected to the reception-side filter, and the antenna terminal connected between the transmission-side filter and phase shifting circuit, and the transmission-side filter is a ladder type surface acoustic wave filter. The outermost arm on the antenna terminal side is a series arm SAW resonator 45b and the transmission-side filter is characterized in that the electric power tolerance to a reflected wave from the output side of a transmit signal is equal to or larger than that to electric power application from the input terminal side.
KAWASAKI TETSUO
SATOU HIROKI
SAKURAGAWA TORU
MURAKAMI KOZO
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