-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi,
at least Window scaling differing between QT and WX is in fact a bit irritating... Cheers :) Marcus On 11/26/2014 12:07 PM, Sylvain Munaut wrote: > Hi, > >> Then: no, QT GUI does that, see [1] (generated by [2]). The tone >> at samp_rate / fft_length * 10 has a power of 0 dB; also, >> Gaussian noise with an amplitude of 1 has an average (picture is >> heavily averaged) power of -20 dB == 1/fft_length. Perfect! > > Oh, that's interesting. > > I didn't see that when I did the test here. Turns out it's the > window selection, if you select Rectangular, you have 0dB and it's > consistent between WX and Qt. > > If you select something else, then it's no longer 0dB and it > becomes inconsistent between the WX and Qt widgets. Now obviously > windowing will have some effect on the peak value, but: - I didn't > expect it to be this large, I expected more like a few tenth of dB, > not precisely 3 or 6dB. - I certainly don't see why Wx or Qt would > make a difference > > >> To the complex vs. real discussion: Picture [3] tells me that I >> see the noise at -23 dB; now, this will get extremely >> philosophical whether when observing a real signal this should be >> -20 dB instead. > > Yes, it's definitely more of a philosophical question than anything > else. Honestly I don't really care either way, I just though I'd > bring this up at the same time and see if there was a "convention" > that was expected. > > Cheers, > > Sylvain > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJUdbtlAAoJEAFxB7BbsDrLzggH/0AwVlFLkoGBdmwqRrrQkW17 YDoXMpk/RMKRwYECoXYw/mr4tDk2OqwwM2I9IfLQwb/tWc7YF5ocXipbtJMdb4tL yiaISddiEyspcT/7KAwNeRYXU61dFPCJBkp9+2TI/kGoH6qIDM4+fW5C3dkQqeaa SdVQMWySWNAmtYBoyxOyGem7UWamNOPw9cVCpcGV3xbmjw/IJGm9DZgHLJ5fwSUA Epzy+D+XGflfPQlpFoeuGw7zo21/PN6BP+OxFaL7eFk1YYgiYcXeS/kl1AENxQkE OnGy2y7lQOqCJe7SAGArARANp1x5926yXM4aS9keUUFsGqT/uoATvUis6i/O+8c= =TuxP -----END PGP SIGNATURE----- _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
