| 摘要 |
PURPOSE:To eliminate an influence of a reflected wave from an input signal, by combining part of an output signal obtained by branching with the wave reflected at the input terminal with equal amplitude and different phases. CONSTITUTION:An input signal from signal input terminal 1 is partially reflected at the input terminal of amplifier 3 and the remainder is outputted from signal output terminal 2. A signal branched from the output signal by output-side directional coupler 8 is made out of phase with the reflected wave equal in amplitude to the reflected wave by phase shifter 7 and led to a signal input line by input-side directional coupler 9. Therefore, the reflected wave and combined wave are equal in amplitude and out of phase, and consequently the both cancel each other, so that since no output appears at input signal terminal 1, an influence of the reflected wave from the input terminal of amplifier 3 can completely be eliminated to improve input impedance. |
