This invention relates to a method for detection of a position of a wave front in a signal received by a detector. This method includes converting the signal into a digital signal, defining a working group of N successive samples in the digital signal, and processing at least some of the samples in the working group. Energy of the signal is calculated from the processed samples in the working group in terms of the root mean square over a sliding window, the window including an optimum number Lopt of samples (Lopt is less than N). Also included is detecting the position of the wave front corresponding to the position of the sample for which the energy of the signal exceeds a threshold D that depends on the value of the energy of the signal previously at the wave front, for the first time.