An AMTI radar system utilizes a three-aperture interferometric antenna having substantially identical beamwidths on each of the three receiving channels. A switching network connected to first the left and center aperture and then the center and right aperture alternates during each pulse repetition interval to couple the radar returns from the three receive apertures to two processing channels. Conventional motion compensation is performed on the data sets of radar returns in each of the two channels. The data sets in each channel are then delayed by one pulse repetition interval and combined with corresponding undelayed data sets. During alternate pulse repetition interval in each channel, valid data sets are gated to an array storage. Fast Fourier transforms are then taken to transform the data sets in each channel into the frequency domain, so that separate range doppler maps of the radar returns can be formed in an array storage unit. In other words, one doppler map is from the left and center apertures while the other range doppler map is from the center and right apertures. A detection and validation processing is performed to provide accurate moving target information in range, doppler, angle and amplitude.