A radar receiver has plural antenna system processors each for performing coherent integration on the basis of correlation values between a reception signal and a transmission signal using correction amounts for phase variations corresponding to plural Doppler frequencies, plural correlation matrix generators for generating, for each of the plural different Doppler frequencies, correlation matrices which are pieces of phase difference information relating to an arrangement of reception antennas on the basis of sets of outputs of the coherent integration, respectively, an adder for adding together outputs of the plural correlation matrix generators, and an incoming direction estimator for estimating an incoming direction of reflection waves on the basis of outputs of the adder.