Abstract: A method for detecting series of substantially periodic bursts of substantially sinusoidal signals, in particular, but not exclusively, series of bursts of signals transmitted recurrently (by pingers for example), this method making it possible to ensure the quick and reliable detection of such signals in the presence of significant interference noise. This method includes slightly delayed processing of received signals, spectral analysis and time integration, and presentation of the results in the form of a two-dimensional image of the successive recurrences of the bursts according to time slots of the received signals.

Abstract: A method for detecting series of substantially periodic bursts of substantially sinusoidal signals, in particular, but not exclusively, series of bursts of signals transmitted recurrently (by pingers for example), this method making it possible to ensure the quick and reliable detection of such signals in the presence of significant interference noise. This method includes slightly delayed processing of received signals, spectral analysis and time integration, and presentation of the results in the form of a two-dimensional image of the successive recurrences of the bursts according to time slots of the received signals.

Abstract: The sounder according to the invention comprises two transmit-receive antennas (1, 10) whose respective axes are off-target toward the front, in the direction of movement of the platform, these axes being symmetrical relative to a straight line (3) passing through their intersection and parallel to the axis of travel of the platform, the transmit frequency of the first antenna, equal to the receive frequency of the second being different from the transmit frequency of the second, the latter frequency being equal to the receive frequency of the first.

Abstract: The sounder according to the invention comprises two transmit-receive antennas (1, 10) whose respective axes are off-target toward the front, in the direction of movement of the platform, these axes being symmetrical relative to a straight line (3) passing through their intersection and parallel to the axis of travel of the platform, the transmit frequency of the first antenna, equal to the receive frequency of the second being different from the transmit frequency of the second, the latter frequency being equal to the receive frequency of the first.