We are giving away all the secrets. The only secrets in SDR DSP are how
to make a complex filter and how to overlap-NNN based convolution of an
FIR. All the rest is glue logic.
;-)
Bob
Charles Swiger wrote:
On Fri, 2006-03-10 at 11:40 -0500, Bob McGwier N4HY wrote:
I missed this question for 3 days.
it took 3 days to hit the list
Yes we do. And here is how it works
It makes a real, low pass filter with cutoff
(H-L)/2
and then spins the coefficients to the correct frequency using a complex
sinusoid.
It is used in a few places in usrp_wfm_rcv_pll.py
Oh - found it - cool. There it is in blksimpl/wfm_rcv_pll.py:
stereo_carrier_filter_coeffs = gr.firdes.complex_band_pass(20.0,
can make this beautiful response:
http://webpages.charter.net/cswiger/filter_response.jpg
Voila, single-sideband.
BTW I recently fixed a broken decimation rate (11 -> 16) in Mike's
examples apps/hf_radio - now is sounds much better.
tks
--Chuck
--
Robert W. McGwier, Ph.D.
Center for Communications Research
805 Bunn Drive
Princeton, NJ 08540
(609)-924-4600
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
