Domenico wrote:
> a little signal, but decoded also here
Excellent result. That's the sort of test I like to
see, where Eb/N0 = 0.7 dB and the program will have
had to search for the phase and it had to use some
list decoding. That's a proper weak signal test.
I guess it should stand another dB weaker.
The 21:30 just decoded here with Eb/N0 = -0.6 dB and
the phase pattern was -30 -60 -30 -60, might be
propagation or my timing system having a hiatus.
The symbol timing of the 21:00 looked good. I tried
some time shifts both ways and it didn't improve.
Markus wrote:
> It seems that non-existing symbols with null
> amplitude are not being counted as symbol
> errors, which severely biases the error rate.
Yes it looks like you're right, the zero symbols are
not counting as errors. They contribute neither positive
or negative to the accumulated log-likelihood of the
path metric. It's effectively an erasure code. I'll
alter the BER arithmetic tomorrow, it probably should
consider only the non-zero symbols. Might need some
thought.
Have to go out now but the rx continues recording.
--
Paul Nicholson
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