Abstract: Disclosed is a method for signaling the presence of a potential obstacle, such as a pedestrian (P) to a vehicle driver (V), in particular a machine driver, wherein each obstacle (P) is provided with a transmitter (Em) capable of outputting a presence signal of the obstacle, and including two at least substantially orthogonal transmitting antennas (A1, A2) and power supply device (1-5) suitable for outputting in-phase quadrature signals to the antennas, and each vehicle (V) is provided with a receiver (Re) including two at least substantially orthogonal receiving antennas (Ax, Ay).