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Homework Help: Cross correlation

  1. Sep 1, 2007 #1
    1. The problem statement, all variables and given/known data
    A signal x(t) is transmitted and received back as y(t) and sampled in the receiver, so we get a DT signal
    y[n] = ax[n-D] + w[n], where w[n] is noise

    baiscally i need to explain how we can measure the time delay by computing crosscorrelation Ryx(l).

    My undestanding is:
    cross-correlation measures how similar the signals are, so if we ccompute cross correlation of a signal with its reflected version, we will get shifted peaks, and the amount of shifting is the delay

    Is this correct?
  2. jcsd
  3. Sep 10, 2008 #2
    Can you please solve it?
  4. Jan 22, 2012 #3
    I realize this is a super old thread. But I was about to ask the exact same question. So I figure I would try bumping it up.

    My understanding is very similar to EvLer's. I have a transmitted pulse x(t) and the received pulse is x(t). These are received by a receive and processed to determine the time delay. The distance from the reflecting object is the time delay.

    Can anyone provide a little more information to make things clearer or confirm what is above in post or Evler's?

    Thanks in advance!
  5. Jan 23, 2012 #4

    I like Serena

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    Homework Helper

    Hey Evo8! :smile:

    I can confirm what is in Evler's post.

    The cross correlation of x and y has a peak at position D.
    Cross correlation can typically be computed with a transform (DFT or other).
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