Noise reduction is a difficult problem and hearing aid manufacturers
have been trying to solve it for the last couple of decades.
One important point to note is that noise reduction is normally aimed at
reducing subjective noise and therefore reducing fatigue. Generally
what you are doing is actually recognising signal, then suppressing
those frequencies that are not conveying the signal. The noise on the
same frequencies as important parts of the signal still gets through.
You cannot remove noise unless you have first identified the signal, so
you cannot remove the noise that is masking an unknown signal.
The simplest noise reduction is a narrow band CW filter! The ultimate
noise reduction for CW would be to decode the signal, and regenerate it,
but that is currently only possible for signals that are already clean
an well formed.
Decode and recreate might be the ultimate solution for hearing aids, as
well.
--
David Woolley
Owner K2 06123
On 06/02/16 03:35, drewko wrote:
I'm glad that noise solutions are being investigated. I think advances
in NR/NB would be of more importance to many hams than close-in dynamic
range, however useful the improvement in those attention-getting figures
are. On a day to day basis noise is the top culprit for many of us.
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com
