So here is a trace, it’s not jumping around but i’ve found an MLAT position in the json while view1090-fa shows it as a synthetic MLAT message.
cpr-debugging/A0D98D-with-mlat-input at master · wiedehopf/cpr-debugging · GitHub
now: 910.0 seen_pos: 6.5 mlat: [track baro_rate] lon:-122.219497 lat:37.716111
*92a0d98d900544b99ac421a5eefc;
CRC: 000000
This is a synthetic MLAT message.
DF:18 AA:A0D98D CF:2 ME:900544B99AC421
Extended Squitter (Non-Transponder) Airborne position (barometric altitude) (18)
ICAO Address: A0D98D (TIS-B)
Baro altitude: -100 ft
CPR type: Airborne
CPR odd flag: odd
CPR latitude: 37.71611 (23757)
CPR longitude: -122.21950 (50209)
CPR decoding: local
NIC: 8
Rc: 0.186 km / 0.1 NM
To create these traces i’ve used view1090-fa and pointed it at the dump1090-fa out with forward-mlat enabled and used show-only to avoid the noise of the other planes.
In the webinterface i was logging the data it got from the aircraft json for the same plane.
New line is written whenever the position in the json changes.
This is the same trace without any MLAT input:
cpr-debugging/A0D98D-no-mlat-input at master · wiedehopf/cpr-debugging · GitHub
Note that the position changing to undefined also shows some problem.
The position goes to undefined while the dump1090-fa without the MLAT data decodes the position just fine.
Or rather the position is decoded in both cases but the dump1090-fa with the MLAT input doesn’t use the position in the json?