Training oriented along the path of sar satellites

The invention relates to a signal processing method and guiding various instruments comprising means (1) forming synthetic aperture radar for observing a target (6), the instrument having at least one pair formed of a transmitter and a receiver, characterized in that the repeated addition, corrected for AIR path differences to the target, in complex mode of samples from a plurality of pairs each differing by their transmitter and / or receiver, all additions being made on pairs whose midpoint is located substantially in a local coordinate system tied to the target and at the time of the corrected addition, on the same section (13) path substantially corresponding to the length of the synthetic antenna formed by the radar (1).