Re: [Starlink] Starship's 4th flight test was magnificent

[Ulrich Speidel <u.speidel@auckland.ac.nz>]

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On 10/06/2024 2:38 pm, David Lang via Starlink wrote:
>
> the V2 were about 8-10x the capacity of the V1.5 (the ones they could 
> launch 50-60 per flight), the v2 mini they have been launching 
> (~22/flight) are about midway between the two. No recent word on the 
> V2s, but Tim Dodd did another starbase visit with Elon before the 
> flight, so watch for that to show up soon.

I think it'd be useful we could agree on what we mean by "capacity" 
before we start throwing numbers around, especially relative ones. For 
Starlink, I can think of the following capacities (yes, plural):

  * User up-/downlink capacity from/to a single user. (How many bits/s
    can I throw at a Dishy?)
  * Downlink capacity to all users in a single cell (under the proviso
    that we don't have any users in adjacent cells that need / want
    service - think small island in the middle of the Pacific).
  * Overall user downlink capacity from a single satellite to multiple
    cells. (Can't deploy co-frequency beams with identical polarisation
    to the same cell if you have multiple such beams on your bird, but
    can do so if we can aim them at different cells)
  * Gateway uplink capacity (to users served directly by the satellite
    or indirectly via ISLs)
  * Gateway downlink (from users served directly by the satellite or
    indirectly via ISLs)
  * Dto. per gateway (see co-frequency beam issue)
  * Processing capacity: Number of bits / s that a satellite can pump
    between its receive beams / incoming ISLs and transmit beams /
    outgoing ISLs.

It's getting late and I probably forgot one or two ;-)


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Dr. Ulrich Speidel

School of Computer Science

Room 303S.594 (City Campus)
Ph: (+64-9)-373-7599 ext. 85282

The University of Auckland
ulrich@cs.auckland.ac.nz
http://www.cs.auckland.ac.nz/~ulrich/
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