Unique criterion to estimate the performances of some laser diode range finders

The purpose of this paper is to present a general method to estimate the intrinsic performances of some laser range finders based on flight time measurement. Classically this flight time can be measured directly, or after a conversion into a phase shift, or into a beat frequency. We prose here a criterion based on signal processing notions, as matched filtering to get the best detection, and ambiguity function to estimate the quality of the detection. The concept of characteristic length is introduced and applied to the different kind of laser range finders, which suggest a new possibility for flight time measurement.