Hi Raydel,
try Keep N in M (keep 1 in N) for the "sampling".
However, if you correctly employ a PLL, your phase will be static; if it's not, 
than the PLL is not doing it's job well.

Greetings,
Marcus

On 10/22/2013 05:21 PM, Raydel Abreu (CM2ESP) wrote:
Hello all,

I am new to GNU Radio and I am still learning the basic. I have a quick question. What 
blocks and which way can I use in order to "sample" and know the phase of a 
tuned carrier at regular intervals.

General idea: Let's suppose there is a carrier, after applying proper tuning 
(Freq Xlating FIR Filter, etc), I apply a PLL module (not sure which: PLL 
Carrier Tracking or PLL Ref Out) in order to remove possible drift from the 
receiver and output a steady carrier. How can I sample at regular interval that 
corrected carrier phase. Assuming that intervals are really equals I guess 
every time I should obtain the same phase value.

I will really appreciate any help in this matter, perhaps someone could point 
me in the right direction.

My purpose is to observe ionospheric phase scintillation from a geostationary 
satellite beacon, which outputs a steady carrier. Frequency drifting should be 
related to RTL-SDR dongle and part of phase changes related to ionospheric 
irregularities.

I attempted something similar with SpectrumLab and an analogue receiver but due 
to receiver drifting and sound card poor sampling stability the phase result 
was a phase rotation of several degrees by measured interval. Perhaps GNU Radio 
and the PLL functions it has could help to overcome the frequency drift in the 
measured carrier.

Thanks in advance,

Raydel.


_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

Reply via email to