Noise addition DICK type microwave radiometer and calibration method thereof

The invention relates to the technical field of microwave radiometers, and discloses a noise addition DICK type microwave radiometer which comprises a measuring switch, a directional coupler, a dicke switch, a square law detector, a low-frequency amplifier, a synchronous integrator, a synchronous detector, an integrator and a square wave generator. The measuring switch is arranged at the signal input end of the directional coupler and is used for controlling whether additional noise is input to the directional coupler or not; the signal output end of the directional coupler is connected to the dicke switch; the square law detector is arranged at the signal output end passing through the dicke switch, and the square law detector is used for outputting voltage. According to the novel system of the noise addition comparison type radiometer provided by the invention, the measurement result of the radiometer is not influenced by the gain change of the system and is also not influenced by the equivalent noise tempe