Riccardo wrote:
> f = 8270.0033187866 Hz
> Start time: 20:00:00 UTC
> Symbol period: 60 s
> Characters: 2 (repeated)
> CRC bits: 10
> Coding 16K21A
After four repeats the results are now:
Todmorden 1413km
----------------
17/18th Eb/N0 +4.0 dB, -31.5 dB in 1Hz, phase -117.5 deg *decoded*;
18/19th Eb/N0 +6.0 dB, -29.5 dB in 1Hz, phase +8.7 deg *decoded*;
19/20th Eb/N0 +7.6 dB, -27.9 dB in 1Hz, phase -35.7 deg *decoded*;
20/21st Eb/N0 +4.6 dB, -30.9 dB in 1Hz, phase -164.7 deg *decoded*;
Bielefeld 845km
---------------
17/18th Eb/N0 -3.1 dB, -38.6 dB in 1Hz, phase -27.7 deg;
18/19th Eb/N0 +0.2 dB, -35.3 dB in 1Hz, phase +111.2 deg *decoded*;
19/20th Eb/N0 +1.4 dB, -34.1 dB in 1Hz, phase +56.5 deg *decoded*;
20/21st Eb/N0 +2.4 dB, -33.0 dB in 1Hz, phase -80.9 deg *decoded*;
Cumiana 371km
-------------
17/18th Eb/N0 +1.1 dB, -34.4 dB in 1Hz, phase +139.2 deg *decoded*;
18/19th Eb/N0 +0.9 dB, -34.6 dB in 1Hz, phase -96.4 deg *decoded*;
19/20th Eb/N0 -8.3 dB, -43.8 dB in 1Hz (rx timing fault)
20/21st Eb/N0 -5.4 dB, -40.9 dB in 1Hz (rx timing fault)
Warsaw 1035km
-------------
17/18th Eb/N0 -5.8 dB, -41.3 dB in 1Hz, phase -28.3 deg;
18/19th Eb/N0 -3.1 dB, -38.6 dB in 1Hz, phase +88.7 deg;
19/20th Eb/N0 -1.8 dB, -37.3 dB in 1Hz, phase +97.1 deg;
20/21st Eb/N0 -10.8 dB, -46.3 dB in 1Hz
Getting reliable decodes at Bielefeld. Cumiana not timing the
signal very well, many thousand timing breaks each day
since something went wrong at 2017-12-19 06:42.
> A new transmission scheduled this night, trying a true
> "stacked decode" in Warsaw:
For unknown reason a poor S/N at Warsaw 20/21st.
Stacking 18/19th + 19/20th produces a false decode at +1.6 dB,
beating the correct decode at +0.5 dB. Pure bad luck there.
Phase shifts from 18/19th to 19/20th:
Todmorden: -44.4
Bielefeld: -54.7
Warsaw: +8.4
Phase shifts from 19/20th to 20/21st:
Todmorden: -129.0
Bielefeld: -137.3
Still something is changing the phase from one night to the next.
--
Paul Nicholson
--
|
