ultrasonic distance measurement using phase shift detection
How doe sa typical sonar work? -> you send a tone burst with a frequency of 40Khz using ultrasonic tyransceivers. The problem is that this method is not very accurate because you will always 'lose' a couple of samples (startup of the transmitter and receiver). You can use a different technique to measure distances with a very high accuracy using an other technique known as phase-shift measurement. In stead of sending a short burst and measuring the time between sending and receiving, you send a constant stream (sine wave at 40Khz) and you measure the phase difference between the outgoing and incoming signal. Obviously you can do only relative measurements, and not absolute.
How doe sa typical sonar work? -> you send a tone burst with a frequency of 40Khz using ultrasonic tyransceivers. The problem is that this method is not very accurate because you will always 'lose' a couple of samples (startup of the transmitter and receiver). You can use a different technique to measure distances with a very high accuracy using an other technique known as phase-shift measurement. In stead of sending a short burst and measuring the time between sending and receiving, you send a constant stream (sine wave at 40Khz) and you measure the phase difference between the outgoing and incoming signal. Obviously you can do only relative measurements, and not absolute.