There is described a method of associating a pulsed signal to a corresponding reference pulse shape. The method generally has accessing reference data having a plurality of reference pulse shapes, each reference pulse shape having a sparse array of average coefficients; receiving a pulsed signal having an array of amplitude values, including generating a sparse array of instantaneous coefficients based on said pulsed signal for example using a discrete wavelet transform; calculating a plurality of first distances between said instantaneous coefficients of said sparse array and the average coefficients of each one of said reference pulse shapes, said first distances having a first minimal distance identifying a closer one of the reference pulse shapes; and upon determining that said first minimal distance is below a first distance threshold, associating said sparse array of instantaneous coefficients to the closer one of the reference pulse shapes.