System for characterizing motion of an individual, notably a human individual

System (1) for characterizing motion of at least one individual forming a target, comprising a radar emitting pulses of electromagnetic signals towards the target and receiving echoed pulses, output as radar data, preprocessing means (11) receiving radar data as input and outputting a spectrogram representing time variations of the Doppler spectrum of the radar data, characterizing means (13) configured for outputting a state vector of the target, the system being characterized in that said state vector comprises at least one target gait classification variable determining one target gait among a set of determined gait models, and a set of motion parameters, the characterizing means comprising a particle filter (15) estimating said state vector from said spectrogram, on the basis of one known individual model among a set of known individual models as a function of said target gait classification variable value, and radar means model.