To provide a microwave frequency converter to be used for a radar receiver capable of receiving signals from a far distance up to an extremely near distance.

A pulse-modulated microwave signal (RF signal) inputted to a limiter 20 is branched to a branching circuit 23 before applying the RF signal to an RF amplifier 22 and the direct RF signal is applied to the RF amplifier 22 and amplified. The branched RF signal attenuated by ten and several dB to twenty and several dB as compared with the direct RF signal is applied to a single balance mixer 24. An output from the RF amplifier 22 is applied to a double balance mixer 25. An output from a local oscillator 26 is applied to the local oscillation terminals of both the mixers 24, 25. IF outputs from the mixer 25 are synthesized by an IF output synthesizer 27 and the synthesized output is applied to an IF amplifier 29. An IF output from the mixer 24 is directly applied to an IF amplifier 31. Outputs from both the IF amplifiers 29, 31 are detected and added by a detection/addition circuit 32 and an added result is outputted from the circuit 32 to display an image on a radar display device.