Satellite name doesn't match with Celestrak TLE data about iridium-toolkit

[schneider42]

The SV number in the Ring Alert messages is a 7 bit field. Originally it simply contained the IRIDIUM XY number of Block 1 SVs.

With the introduction of Iridium Next, this field became to small (66 * 2 < 2**7), so Iridium started to reuse numbers of (de-activated / de-orbited) Block 1 SVs. This means that the SV number in the Ring Alert message does not equal the IRIDIUM XYZ number anymore.

We haven't looked into this anymore but it should be trivial to create a table which provides a mapping from SV number in the Ring Alert to "IRIDIUM XYZ" designation. Wanna try? ;)

[Sec42]

I just pushed code to do this in 2e3d1aa.

You will need to install the python3 skyfield module and have TLE data in tracking/iridium-NEXT.txt - which you can fetch/update that by running cd tracking && ./update-tracking

Pipe some parsed IRA into reassembler.py -m satmap and it should output a mapping for those based on TLE data.

Please note that the TLE data and your received IRA frames need to be the same age. If they differ by more then a couple of days, accuracy of the mapping may be reduced.