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Ultrasonic Sensors

  1. Dec 4, 2006 #1
    I have a question regarding ultrasonic sensors. Let's say for example I want to use a typical ultrasonic sensor, in this case lets say: http://www.jameco.com/webapp/wcs/st...toreId=10001&catalogId=10001&productId=136653

    in a circuit for distance detection. How would I hook it up for use?
    Or if someone could direct me to a resource or something that could help me understand how to place these things in circuits.

    Im fairly new to the sensor area in EE. Do I apply a voltage on one end, and expect as response voltage on the other? Thanks in advance guys.
  2. jcsd
  3. Dec 5, 2006 #2


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    Staff: Mentor

  4. Dec 5, 2006 #3
    Many thanks on the links, now perhaps a physicist can enlighten me, can the sounds waves at 40KHZ on a range sensor penetrate walls if operating within operational range? Or would the sound waves always be bounced off walls or windows and not get through to the other side?
  5. Dec 5, 2006 #4
    A proportion will reflect and a proportion will penetrate each density boundary. In general the higher the frequency the greater the reflection, but it is very material dependent.

    If you want to just detect surfaces then use a plain pulse and detect the first return.

    If you want to detect embedded objects or inclusions then use a coded pulse and detect each return time resolved through a matched filter. By estimating the speed of sound through the material you can calculate the depth of the density boundary.

    Another advantage of pulse encryption is that you can seriously overdrive the TX transducer getting much improved range, providing you follow the power derating curves in the spec sheet.
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