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0 pointsmrb2y ago0 comments

FTA: "in some cases, the links can also be maintained for weeks at a time"

I think there is a lot of variance. The article also states about 266,141 “laser acquisitions” per day, which, if every laser link stayed up for the exact same amount of time, with 9000 lasers, means the average link remains established for a little less than an hour: 9000 (lasers) / 266141 (daily acquisitions) * 24 * 60 = 49 minutes

So some links may stay established for weeks, but some only for a few minutes?

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jandrese2y ago

I would guess that the links between satellites on the same orbit stay for weeks, but the ones that cross between orbits have to constantly re-established.

schiffern2y ago

Correct.

I believe Starlink (like Iridium) doesn't even try to establish connections "across the seam," ie the one place the satellites in the adjacent plane are coming head on at orbital speed.

This make side-linking easier because the relative velocity is comparatively low, but in general you unavoidably still need to switch side-link satellites (on one side) twice per orbit. Hence 49 minutes: this average must be calculated per connection not per second, so the front/back links (plus random noise) count less, so it only drags the average from 45 minutes up to 49 minutes.

try_the_bass2y ago

I believe Starlink (like Iridium) doesn't even try to establish connections "across the seam," ie the one place the satellites in the adjacent plane are coming head on at orbital speed.

The slide showing the multiple possible paths traffic can take seems to disagree with this statement?

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