Abstract: A synthetic aperture radar (SAR) processes radar has a transmit aperture and a receive aperture that is of a different size from the transmit aperture. The receive aperture is separated from the transmit aperture and is divided into a number of receive sub-apertures arranged in the elevation and azimuth directions. Circuitry is used to process the received radar signal coherently by phase shifting each receive sub-aperture signal by a time and/or frequency variant phase value and by summing the resulting signals from receive sub-apertures arrayed along the elevation direction, whereby the time and/or frequency variant phase value is generated in such a way that the radar echo signal is maximized in the summed signal as the radar transmit signal runs over the earth's surface.

Abstract: The invention relates to a side-looking SAR system, comprising