HI,
Thanks for sharing experience!
Question to FT8 and "noise" relations - In usual case everything in
passband is noise except signal of interest.
So with only one FT8 signal and white noise in passband S/N can be
increased narrowing passband till it matches signal width. EME guys know
that JT65 -16 dB signals are audible.
But if there are many other FT8 signals (which are "noise" since are out
of interest for me) then energy from all these 59++ signals are
integrated as noise and my 57 signal became "very deep in the noise".
If to narrow bandwidth in this case we get rid of QRMing 59++ signals
(and proportional part of band white noise) - they are not integrated
and our signal gets "above noise".
Is this right or there is some magic excluding other FT8 signals from
S/N calculations? Still very doubt in FT8 ability to be decoded 10dB
below CW. -3 dB at best.
73
Arunas LY2IJ
2018-12-20 05:57, Joe Subich, W4TV rašė:
>> Is the definition of "noise floor" being changed for FT8?
> WSJT-X (and WSJT before that) defines noise as the integrated value
> of noise (noise power) across the 2500 Hz (approximately based on
> the receiver filter) receive bandwidth.
>
> 73,
>
> ... Joe, W4TV
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