System and method of time of flight detection

A method for determining a distance between a signal source and a receiver, based on a signal that is recovered from a probe signal transmitted at a predetermined time from the signal source and received and digitized at the receiver, the probe signal comprising a repeating pseudo-random noise (PRN) code signal, the PRN code signal comprising a sequence of sections, each section having a predetermined duration and having samples corresponding to one of a plurality of predetermined waveforms, the method comprising:

• (i) assigning each sample of the digitized recovered signal by an offset time value relative to the predetermined time;
• (ii) dividing the digitized recovered signal into sections, each section having the predetermined duration;
• (iii) aligning in time the sections of digitized recovered signal with the sections of the PRN code signal;
• (iv) associating each section of the digitized recovered signal with the predetermined waveform of the aligned section of the PRM code signal;
• (v) for each predetermined waveform, coherently summing the samples in the sections of the digitized recovered signal associated with the predetermined waveform, and computing a correlation value between the coherently summed samples with the predetermined waveform;
• (vi) summing the correlation values to provide a test correlation value associated with the offset time value;
• and
• (vii) repeating steps (i) through (vi) for different offset time values.