3 ms·
I wonder how iridium actually handles the tracking (or if it’s just slow enough and lack of attenuation in free space just lets them blast it). And if they hav
by Scoundreller 3y ago
I wonder how iridium actually handles the tracking (or if it’s just slow enough and lack of attenuation in free space just lets them blast it).
And if they have zones where they don’t go to adjacent orbits, but instead go up or down within their orbit for the handover between orbits.
- lxgr 3y agoSupposedly they use steering, since the horizontal azimuth to adjacent-plane satellites varies from 0 to 65 degrees across an orbit: https://apps.dtic.mil/sti/tr/pdf/ADA348174.pdf https://apps.dtic.mil/sti/tr/pdf/ADA348174.pdf
- Scoundreller 3y agoIt doesn’t get into it too much on pages 14 and 15, but it indeed suggests that they probably exclusively use the “intra-orbital” links closer to the poles to get data to a satellite where the inter-orbital links are more practical. I believe Iridium had way more downlinks than they used to pre-bankruptcy. I guess volume constraints were less of an issue, so ok to hop around more in space.
- lxgr 3y agoThis has more details: https://fcc.report/IBFS/SAT-MOD-20131227-00148/1031348.pdf https://fcc.report/IBFS/SAT-MOD-20131227-00148/1031348.pdf Apparently it only happens above/below 68 degrees latitude, so the next satellite with a working inter-orbital-plane connection is at most one hop ahead or behind. https://spaceflight101.com/spacecraft/iridium-next/ https://spaceflight101.com/spacecraft/iridium-next/ has some more photos and diagrams; seems like they're really mechanically steered even on the NEXT constellation.