| 摘要 |
A combiner circuit (300), for combining RF signals produced by a Doherty amplifier circuit (100), including a first channel (302), a second channel (304) and an output junction (319), the first channel including a first quarter wave transmission line (309) adapted to receive an RF signal continuously from a first amplifier of the amplifier circuit and to deliver an RF signal to the output junction, the second channel including a second quarter wave transmission line (315) adapted to receive from a second amplifier of the amplifier circuit an RF signal during a high power mode but not during a low power mode of the amplifier circuit and adapted to deliver an RF signal, when received, to the output junction; and a switching arrangement (313, 317) operable to isolate the second transmission line in the low power mode. Also described is an amplifier circuit (100) and an RF transmitter (500) including the combiner circuit. |
