Patent ID: 7640122

Claim:
A method for increasing the signal to noise ratio of the signal waveforms generated by an apparatus for optically sensing a remote object in relative motion along the line of sight of said apparatus, comprising the steps of: (a) providing said apparatus for optically sensing said object, said apparatus including means for (a1) sending a predetermined number N.sub.S of optical pulses towards said object, (a2) receiving a number N.sub.S of optical signals reflected by said object, (a3) converting said number N.sub.S of optical signals into a number N.sub.S of digital signal waveforms S.sub.k, k=1, 2, 3, . . . , N.sub.S, each of the said digital signal waveforms being formed of data sampled at a predetermined number N.sub.p of range values R.sub.i, i=1, 2, 3, . . . , N.sub.p, and (a4) numerically processing said digital signal waveforms, (b) selecting a set of range shift parameter values RSP.sub.j, j=1, 2, 3, . . . , N.sub.R, (c) performing a range shift of each said waveform S.sub.k by the value (k−1).times.RSP.sub.j, (d) generating a waveform SA.sub.j by computing the average of the N.sub.S said waveforms S.sub.k range shifted according to step (c), (e) finding the peak signal amplitude comprised in the averaged signal waveform SA.sub.j, (f) repeating steps (c) to (e) for the N.sub.R values of said range shift parameter RSP.sub.j as selected in step (b), (g) finding the values of said range shift parameter that give averaged signal waveforms having peak signal amplitudes exceeding a predetermined threshold, (h) combining the averaged signal waveforms determined in step (g) and updating a previously measured signal waveform having the maximum peak signal amplitude with said waveform combination.