Re: [Starlink] [LibreQoS] Starlink cell capacity (was; tarana strikes back)

[Jim Forster <jrforster@mac.com>]

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> On Sep 25, 2023, at 4:11 AM, David Lang via LibreQoS <libreqos@lists.bufferbloat.net> wrote:
> 
>>>> 
>>>> https://www.taranawireless.com/a-comparison-of-next-generation-fwa-vs-leo-satellite/ <https://www.taranawireless.com/a-comparison-of-next-generation-fwa-vs-leo-satellite/>
>>>> 
>>>> Can anyone question these Starlink numbers for cell size, etc?
> 
> I think they have the cell size reasonably accuarate (for now), But if the cell sizes were of fixed size and unable to be re-used, once there were enough satellites to provide global coverage, adding more would not provide any value. But even their first phase includes many times the number they needed to provide global coverage, so the assumptions around the capacity being fixed by the initial cell size and a single satellite covering it cannot be correct.
> 
> I question the assumption that there will only be a single satellite serving the cell at a time. With directional antennas (including phased arrays) you can aim both your uplink and downlink.
> 
> Even without having multiple satellites covering a single cell, you can shrink the cells by having the ground stations further from the center of the cell aim at different parts of the sky.

This is all true (as much as I understand),  Worth noting as well, is that with LEOs if one satellite is maxed out serving a cell, then getting a second satellite to help with that cell mean adding *lots* more satellites. If adjacent cells had very different loads then I guess nearby unloaeded satellites could help out their busy neighbors.  But areas with busy cells close together would mean doubling the number of satellites and therefore platform Capex.  Whereas terrestrial towers can be densified in busy areas.  


  — Jim




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