Hello friends,
my comments to the discussion WSPR vs. CW:
(1) Modes only can be compared at a specified data rate.
Of course, CW is "better" than every thinkable digital
mode if we allow it to be slowed down until something
can be identified on the screen. What really counts is
the duration of a random QSO.
(2) Modes only can be compared at a specified error rate.
Try to communicate completely unknown messages! The
symbol error rate of CW at it's ultimate snr is
relatively high. Getting confidence in a callsign
needs a low symbol error rate, i.e. a good snr.
(3) I am working on a digital mode for minimal QSOs.
In simulations with Gaussian noise and Rayleigh fading
it is 1 dB above the Shannon limit. On-off-keying as
used by CW by principle cannot reach that.
Wishing the best for 2009,
73 de Klaus, DJ5HG
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