Carrier of DJ8WX measured in about 80uHz bandwidth. S/N is 18.4dB in
this bandwidth.
http://abelian.org/vlf/tmp/151208a.gif
The magnetic flux density of 0.1fT corresponds to around
30nV/m electric field strength.
Uwe wrote (28th Nov)
> Coding 8k19a
> Characters 2
> Bits 368
> Duration 01:01:20.00
> Start 2015-11-28 17:00:00
> Rpt on hour
> (in between carrier only)
With the above S/N, this should decode at about Eb/N0 = +2.5dB
Uwe wrote (today)
> carrier on the air.
> the message starts at 18:00:00
At 18:00 I am still getting carrier. When I run this into
the decoder it struggles to decode, the noise has come up
since the S/N measurement. I add in the E-field to gain a
couple of dB and then the carrier decodes:
18:00:00 to 19:01:20
found rank 0: ** ps [ 2 30 30 30 30]
re-encode 131/368 ber 3.56e-01 Es/N0=-11.6 Eb/N0=3.3
(Carrier decodes to a string of * characters).
--
Paul Nicholson
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