摘要 |
An amplifier comprises a power amplifier for amplifying an unmodulated high-frequency input signal, a first branching device which is provided at an input terminal side of the power amplifier and extracts a signal, a second branching device which is provided at an output terminal side of the power amplifier and extracts a signal, a mixer for mixing a signal from the first branching device and a signal from the second branching device, a low-pass filter for removing a frequency band component of the input signal from an output signal of the mixer, a high-pass filter for removing a DC component from an output signal of the low-pass filter, and a wave detector for extracting a signal. |