Re: LF: More EbNaut 137.777

[Andy Talbot <andy.g4jnt@gmail.com>]

The 0630 recording gave a decode too

found VO1NA
list rank 22
reference phase  150  150  150  150
carrier RMS 4.329e+002 noise RMS 4.617e+001
carrier S/N 19.44 dB in 976.6 uHz
carrier Es/N0 -7.65 dB
carrier Eb/N0 4.89 dB
info bit period 35.93 seconds
symbol error rate 176/512 = 34.375 %
Es/N0 from symbol errors -10.9 dB
Eb/N0 from symbol errors 1.4 dB
Shannon capacity 411.5 bits/hour
Shannon efficiency 24.4 %
symbols file C:\CohLFRx\151130_0629-symbols.csv
elapsed 52 seconds

Andy  G4JNT


On 30 November 2015 at 08:37, Andy Talbot <andy.g4jnt@gmail.com> wrote:
> I left it running overnight, and have tried a few capture files
> selected at random.   Some produce a garbage message, with symbol
> errors typically 200 or so out of 512 but this one at 0200 gave a
> correct decode immediately with just slightly fewer symbol errors at
> 187   All the contents of the .txt file shown below
>  (unless the one chance in  50 ^ 5 = 315 million threw the correct
> callsign up at random :-)
>
> One thing that puzzles me:
> The EbNaut documentation states there is an outer checksum for message
> validity.    Why does this allow the garbage decodes to get through -
> surely that must be failing the checksum.    Or are they the few out
> of millions of possible garbage decodes that pass the checksum
> criteria?
>
>
> Andy  G4JNT
>
>