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How to derive impulse response from characteristic impedance

  1. Jan 29, 2012 #1
    i have a coax cable that will be used in data transmission. i have measured the open and short impedance and then characteristic impedance(Zo) for the cable. Eventually I will have a transmitter with Z_source in one end of the cable and receiver with Z_load at the other end of the cable. Is it possible to derive impulse response as a function of Zo,Z_source and Z_load?
  2. jcsd
  3. Jan 29, 2012 #2
    Unless the bit rate width is much longer than the coax line, it is not adviceable to to mismatch the source, line and termination impedance. Reflection will create a step change on the logic level and cause error.

    In digital communication, you don't deal with standing wave and those, either you have it or you don't.
  4. Jan 29, 2012 #3
    They all will be matched but i want to analyze the effects of mismatches on BER using impulse response to see how much mismatch is tolerable.
  5. Jan 29, 2012 #4
    To do that, you have to know the threshold of the input of the receiver first, that is the most important thing. Then look up the transmission line reflection on step function. Usually only the first reflection step is the biggest and is proportion to the line and termination mismatch.
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