Forum: GNU Radio carrier-tracking on FSK

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0c03bff8ade87b38c3f5bd7f11a387b4?d=identicon&s=25 George Barrinuevo (Guest)
on 2007-04-20 04:17
(Received via mailing list)

I just created my first 2-level FSK demodulator and
would like to add carrier-tracking to find the carrier
frequency.  Since some RF signals are offset by about
5kHz.  I need a way to zero in on the frequency to
compensate for the offset.  Is there a block that
performs this function?  Or, can someone point me in
the right direction?


George Barrinuevo
0c03bff8ade87b38c3f5bd7f11a387b4?d=identicon&s=25 George Barrinuevo (Guest)
on 2007-04-20 08:44
(Received via mailing list)
I found it.  This is what I found on FM/FSK

        audio_rate = 20000;
        alpha = 5 * 0.25 * math.pi / (audio_rate);
        beta = alpha * alpha / 4.0
        max_freq = -2.0*math.pi*18970/audio_rate;
        min_freq = -2.0*math.pi*19030/audio_rate;

        stereo_carrier_pll_recovery =


There is also gr_pll_refout_cc and gr_pll_freqdet_cf.


--- George Barrinuevo <> wrote:

> the right direction?

George Barrinuevo
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