Abstract: According to this method for transmitting a digital signal by a base station equipped with a multi-element antenna to a mobile, in the presence of interference sources and background noise, at least one frequency transposition operator is calculated which approximately transforms one reception calibration table into one transmission or reception calibration table; statistical data are calculated on the basis of the signals received by the various elements, originating from the mobile and the interference sources; for this mobile, an optimum set of spatial weightings is calculated on the basis of the statistical data, the frequency transposition operator, and a criterion for reinforcing the useful signal and reducing the interference sources; the digital signal is weighted on the basis of the optimum set of weightings, then it is transmitted.

Abstract: The invention relates to a device for locating noise emitters with an antenna comprising passive sensors. In a preferred variant, the antenna consists of N acoustic buoys each comprising a pair of hydrophone dipoles exhibiting a double-eight directivity diagram. Each buoy comprises a compass providing a signal K.sub.n representing the heading relative to magnetic North. The pairs of signals (a.sub.1 -b.sub.1 to a.sub.N -b.sub.N) are subjected to a rotation by the angle K.sub.n. The signals are next digitized and the number P of noise emitters estimated. The locating of these noise emitters can be performed according to two variants (8, 9).