I've just updated simple_fm_rcv to implement a simple Automatic Fine Tuning function.

This function measures DC offset on the output of the demodulator block, and uses that to drive a parameter of the freq-xlating filter block that's on the input. It seems to work OK in my simple tests this evening. This is a piece that typically wouldn't be required if using UHD hardware, but the RTL-SDR radios have, ahem, less-than-ideal master oscillators, so I wanted to see if AFT would be
  possible.

So, in effect, I've implemented a feedback loop within the flow-graph. But it's via a polled value, so it doesn't violate the rules.

--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org



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

Reply via email to