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    Hi Jeon,<br>
    <br>
    is this the mail you were referring to on discuss-gnuradio? I'm
    including it in my reply, because that seems sensible.<br>
    <br>
    What you're looking at looks very much like a synchronization
    problem.<br>
    Manchester tells me we have a reliable rate of transitions, so
    that's handy :) <br>
    I'd go for oversampling (if that's possible) by a factor of let's
    say 4 or 5 of your symbol rate, and implementing a sensible filter
    for the signal; then, throw the Mueller & Müller clock sync
    (Look into the [Synchronizers] categorie in GRC) at the problem :)<br>
    <br>
    Best regards,<br>
    Marcus<br>
    <br>
    <div class="moz-cite-prefix">On 02/20/2015 03:02 PM, Jeon via
      USRP-users wrote:<br>
    </div>
    <blockquote
cite="mid:CACfn7v5bvzBj2_EDLF+w3naoXaXHnKvb2DQ4a8A4-9Na-oXygQ@mail.gmail.com"
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                          <div>I am trying to make something which:<br>
                            <br>
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                          * finds some synchronization timing position<br>
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                        * throws away what comes before sync code<br>
                      </div>
                      * passes what comes after sync code<br>
                      <br>
                    </div>
                    a sync code is '010110' (FYI, It is encoded with
                    Manchester code, so the decoded code is 001)<br>
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                  I have tried:<br>
                  <br>
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                * digital_correlate_access_code_bb with access code
                010110<br>
                * fir_filter_xxx with taps of [0,1,0,1,1,0]<br>
                * interp_fir_filter_xxx with taps of [0,1,0,1,1,0],<br>
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              where values of threshold, decimation and interpolation I
              cannot assure<br>
              <br>
            </div>
            But, I cannot see value 3 which is expected<br>
            if there is perfect timing synchronization for a given
            sample stream ......0101011001......<br>
            <br>
          </div>
          <div>Am I using wrong blocks, or somewhat misconfigured
            threshodl, decimation and interpolation values?<br>
            <br>
          </div>
          <div>If you have an idea for it, please give me some advice.<br>
          </div>
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          Regards,<br>
        </div>
        Jeon.</div>
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