I created 3 new test audio files with Morse code at different signal-to-noise ratios.
See the new visualizations using Morlet wavelet transformation with Morse code at -9dB and -12dB SNR level in the original signals
in here: http://ag1le.blogspot.com/2012/06/ultimate-morse-code-decoder.html
Morlet wavelets seem to provide pretty good time AND frequency resolution at the same time.
This has been a problem with traditional short time windowed Fast Fourier Transformations (SFFT).
With SFFT you can get good accuracy in either frequency OR time domain, but not in both simultaneously.
for more scientific explanation.
I other words this means that wavelet transformation could enable much improved real time CW decoding even for very noisy signals.
What would you do if you could get 12 dB signal-to-noise gain without investing over $5000 to a large multiband Yagi and a tower?
Would you work CW stations that are barely audible or below noise level if this feature would be available in software like FLDIGI?