I'm copying 'V3' with Eb/N0 = +2.0 dB. Reference phase: -30 0 -30 0 Carrier S/N: 10.86 dB in 34.0 uHz Lower noise last night, an average nighttime noise level. -- Paul Nicholson --
It actually keeps the decode with the best path metric. The other options (best rank, best BER) don't perform so well on average. The log file doesn't show the path metric though, I'll fix that for
I found the mistake. Had the wrong date in the vtread command. Doh! Decoded '73' with Eb/N0 = +9.7 dB, constant reference phase. Carrier S/N: 21.12 dB in 34.0 uHz -- Paul Nicholson --
Copied 'DF6NM DK7FC K' Eb/N0 = +1.0 dB and the reference phase pattern -150 -150 180 180 Carrier S/N: 19.42 dB in 37.2 uHz That's 6 of 6 messages decoded. -- Paul Nicholson --
The distance may actually be too short. For medium ranges, say 100km to 500km the phase and amplitude can vary wildly due to the number of competing modes (or rays if you prefer the ray model). When
Indeed, four terminators to cope with. Half the message will have daytime phase and half night time phase and a mess in between. No chance of a decode if day and night phase differs by more than 90
An interesting and challenging long-term experiment would be to watch for whistler mode propagation. Needs a beacon sending a pseudo-random test pattern (which could be an EbNaut message or just a bl
20 hours now, and I ran LWPC which predicts only a 35 degree phase change between day and night. If that works out, then I won't need to do any elaborate diurnal phase compensation, it is well withi
Well worth a try and can be easily tested in simulation. The phase search costs some coding gain because of the increased opportunity for a false decode to overcome the real decode. The squared signa
I was impatient, with still 5549.6 seconds left to go I decoded the message easily, 'CQ CQ DREAMERS BAND DE DK7FC IN JN49IK PSE KK' Carrier S/N: 25.03 dB in 10.3 uHz Eb/N0 = 0.1dB with constant refer
After the full message duration had elapsed, Eb/N0 came to +1.6 dB, Phase: 180 180 150 150 Carrier S/N: 24.96 dB in 10.3 uH Were the last 3 hours corrupted? Without signal, the decoder pads with zero
Error map from Stefan's long transmission, http://abelian.org/vlf/tmp/160429a.gif Each red line indicates a bit error. I can use this recording to try the suggestion by Markus to apply some sort of g
Amateur radio DX at ULF, that would be a result for any dreamer wouldn't it? You've proved that propagation will allow 24hrs at 8.27kHz, and we expect most lower frequencies will be at least as stabl
Copied 'VLFDX' Reference phase: constant Eb/N0: +5.4 dB BER: 26.8 % Carrier: S/N: 19.77 dB in 9.8 uHz Error map: http://abelian.org/vlf/tmp/160502a.gif I am seeing the expected 6dB signal reduction a
A good decode there Markus, close to the limit at 77% of Shannon capacity. Ran LWPC for the path DK7FC to DF6NM and it predicts only 11 degree phase change between day and night. And DK7FC to DF6NM a
No decode so far but that's no surprise. I need to find the right settings for this frequency: calibrating the E and H rx phase and finding the best pre-blanker filter settings. The filter settings
EbNaut partly achieves its close-to-the-limit capability by discarding anything that uses energy to make the signal detectable. With little activity and every transmission an experiment in the unknow
Stefan, Your 200mA carrier comes through well here at 6.47 kHz, nice signal at 0.14 fT during the night. Daytime is 0.04 fT or below and might be a bit of a struggle. I don't need any more carrier. F
I'm getting '73+55' at Eb/N0 = -0.3dB with phase pattern 30 60 30 60 Carrier S/N: 15.25 dB in 19.5 uHz Still working on the first message, noise in the E/W loop was very high that night. Looks like w
