Electronic – Time of flight difference in hardware


I have an ultrasonic emitter, and two ultrasonic receivers. When the emitter emits a pulse, the receivers get the signal at different times. I am only interested in the difference between the two reception times.

At first, I was thinking of using a microprocessor, measuring individual arrival times, and then taking the difference. Taking two absolute measures when only a difference is required feels somewhat unnecessary, and may add inaccuracies.

Is there a way to measure pulse time differences in hardware, i.e. analogically? Would this be advisable?

Best Answer

Use a so called TDC, e.g. the acam-gp21: http://www.acam-usa.com/GP21.html. It even has an example for ultrasonic measurement in the manual.