| 摘要 |
PURPOSE: To make the antenna multicoupler small in size and light in weight and to obtain high performance (low loss) for the multicoupler. CONSTITUTION: An antenna changeover circuit 4 comprising diodes D1, D2 and aλ/4 phase shift circuit 41 is provided among an antenna terminal ant, a transmission filter 2 and a reception filter 3, and a control signal received from a control terminal CONT is used to select the connection between an antenna ANT and the transmission filter 2 or select the connection between the antenna ANT and the reception filter 3. The intrusion of a transmission signal to a receiver side or the intrusion of a reception signal to a transmitter side is prevented through the selection of the connection between the antenna ANT and the transmission filter 2 or the reception filter 3 so as to relax the attenuation characteristic at a cut-off frequency of both the filters and high power resistance of the reception filter.
|
