摘要 |
An attenuator includes a first 3 dB bridge, a second 3 dB bridge and an amplifying tube group, where the amplifying tube group includes a first amplifying tube and a second amplifying tube, a drain of the first amplifying tube is connected to a first output port of the first 3 dB bridge, a source of the first amplifying tube is connected to a first input port of the second 3 dB bridge, a drain of the second amplifying tube is connected to a second output port of the first 3 dB bridge, and a source of the second amplifying tube is connected to a second input port of the second 3 dB bridge; where gates of the first amplifying tube and the second amplifying tube are respectively connected to the same voltage source or different voltage sources having the same voltage. |