Abstract: A computer-implemented method includes receiving a series of measurements of distances generated, from a plurality of different positions each time, by a detection system operating by: transmitting a wave; receiving waves reflected by the environment; determining the distances by calculating differences between the wave transmission time and the time of reception of the reflected waves; generating, based on the series of distance measurements, a synthetic image representing the distances from the environment relative to a reference position; for each focal distance of a plurality of focal distances: generating, from the series of distance measurements or the synthetic image, a synthetic image that is focused at the focal distance, by applying compensation for penumbra effects; and detecting the presence of an object in the focused synthetic image.

Abstract: A synthetic aperture sonar moving along a first axis comprises an emitting device configured to emit, in each ping, at least one acoustic pulse toward an observed zone in a set of sectors comprising at least one sector. The sonar comprises a first physical receiving antenna extending along the first axis allowing measurements of backscattered signals to be acquired and a processing device configured to form, over R pings, for each sector, synthetic aperture beams from measurements of signals backscattered by the observed zone and generated by acoustic pulses emitted in the sector. The sonar comprises at least one gyrometer. The processing device is configured to correct for variations in the movement of the first receiving antenna during the formation of the synthetic aperture beams of the set of sectors by carrying out an autocalibration by intercorrelation of the successive pings.

Abstract: A synthetic aperture sonar moving along a first axis comprises an emitting device configured to emit, in each ping, at least one acoustic pulse toward an observed zone in a set of sectors comprising at least one sector. The sonar comprises a first physical receiving antenna extending along the first axis allowing measurements of backscattered signals to be acquired and a processing device configured to form, over R pings, for each sector, synthetic aperture beams from measurements of signals backscattered by the observed zone and generated by acoustic pulses emitted in the sector. The sonar comprises at least one gyrometer. The processing device is configured to correct for variations in the movement of the first receiving antenna during the formation of the synthetic aperture beams of the set of sectors by carrying out an autocalibration by intercorrelation of the successive pings.