Abstract: The invention relates to sonar transmission means and in particular to transmission means for achieving omnidirectional acoustic transmission. The invention relates to a method for achieving omnidirectional transmission using of a towed linear antenna of length L greater than the wavelength ? of the signal transmitted. The antenna has a plurality of P projectors. The spacing between projectors is substantially less than ?/2. The method according to the invention includes applying, to each projector, a transmit signal coming from a common transmit signal. The common signal is assigned a delay, the expression for which follows a law containing a non-linear term as a function of the position of the projector in the antenna. Application of this law allows the angular aperture of the transmission pattern to be modulated.