[Starlink] Starlink filings for D-Band via Tonga

Alexandre Petrescu alexandre.petrescu at gmail.com
Thu Nov 23 08:40:02 EST 2023


Le 17/11/2023 à 23:56, Ulrich Speidel via Starlink a écrit :
>
> Right. Word from the Tongan government's MEIDECC is that it's D band 
> as per the filing and that the reports on W band are wrong.
>
Can MEIDECC point me to the precise place at the ITU filing that says 
it's D band?  Thank you!

I could not find the word 'D-band' or 'D band' in the 'ESIAFI 
application file  ("'ESIAFI II API-A(1).mdb"  at ITU 
https://www.itu.int/ITU-R/space/asreceived/Publication/DisplayPublication/53068)

People nominate bands in various ways.  As an example of a potential 
confusion, there is this other wikipedia image that shows the freqs in 
question (123-ish, 170-ish GHz) being called 'EHF' by ITU and 'W' by 
IEEE.  Further to the confusion, the diagram says that the EU, NATO and 
US ECM (not sure what  is ECM) call 'D' band something around 2 GHz or 
so, which is much lower than this 123-ish, 170-ish GHz. 
https://en.wikipedia.org/wiki/Radio_spectrum#/media/File:Frq_Band_Comparison.png

I will look later at maybe joining that ITU group to ask it there as well.

Alex

> Beyond that, they're not authorised to say anything except that yes, 
> it's a genuine filing.
>
> I don't think Tonga is a likely launch base (no large tracts of land 
> to launch a rocket from, except as some locals would probably tell 
> you, from the driveway of a certain royal residence). Who knows.
>
> I'd also say that SpaceX filings to the FCC at least have a track 
> history of being superseded by the next filing a few weeks later with 
> completely different parameters. Whether that's just rapid prototyping 
> at SpaceX or whether they're deliberately designed as a groundhog 
> version of April Fool's Day for the competition's lawyers to keep them 
> spend money on litigation while SpaceX spends on innovation is 
> anyone's guess. Similarly, having slept over it, the Tongan story 
> could be a SpaceX attempt at establishing a "flag of convenience" 
> operation, or it could simply be another of Elon's pranks to whip us 
> and the media all up into a frenzy to keep people talking about his 
> enterprises.
>
> On 17/11/2023 11:43 pm, Ulrich Speidel wrote:
>>
>> OK, so this seems to be related to a somewhat bigger development that 
>> Starlink is pushing through Tonga as the regulatory authority:
>>
>> https://www.reddit.com/r/spacex/comments/175ttvz/spacex_files_29988satellite_wband_network_using/
>> https://www.spaceintelreport.com/spacex-files-29988-satellite-w-band-network-using-kingdom-of-tonga-as-regulatory-home/
>>
>> ESIAFI 1 was bought by Tonga - it was the old COMSTAR 4 satellite and 
>> named after their women's rugby team.
>>
>> Quite why they've chosen Tonga as regulatory home - no idea. Maybe 
>> because they think Tonga owes them a favour. Currently trying to find 
>> out more - stay tuned.
>>
>> On 17/11/2023 6:29 am, David Fernández via Starlink wrote:
>>> Hi Alex,
>>>
>>> "A person on twitter seems to be saying this filing is precisely the
>>> filing that spacex did at FCC"
>>>
>>> Would you mind linking to that tweet, if it is public?
>>>
>>> Thank you.
>>>
>>> Regards,
>>>
>>> David
>>>
>>>
>>> > Date: Thu, 16 Nov 2023 14:27:03 +0100
>>> > From: Alexandre Petrescu <alexandre.petrescu at gmail.com>
>>> > To: starlink at lists.bufferbloat.net
>>> > Subject: Re: [Starlink] Starlink filings for D-Band via Tonga
>>> > Message-ID: <805d52ce-b517-49b9-a053-8306cd20b8aa at gmail.com>
>>> > Content-Type: text/plain; charset=UTF-8; format=flowed
>>> >
>>> > Towards clarification,
>>> >
>>> > The .mdb file of the ITU filing can be read with Excel (tab Data ->
>>> > leftmost button 'Access'). The .mdb is on the web page of the ITU
>>> > filing, at the bottom of the page.
>>> > 
>>> https://www.itu.int/ITU-R/space/asreceived/Publication/DisplayPublication/53068
>>> >
>>> > It might be that this 'ESIAFI II' is just a name because of some 
>>> reason.
>>> >
>>> > There are some interesting dates like '06/03/2023', '13/03/2023' and
>>> > '20/03/2023' and '6/10/2023'.
>>> >
>>> > There is much data about orbits, powers, beams that I dont know how to
>>> > interpret. I would need the precise description of the database 
>>> format,
>>> > but I dont know where to get it from.
>>> >
>>> > The frequencies are listed, as I interpret these fields: 123 GHz - 130
>>> > GHz centered on 126.5 GHz, 158.5-164 c 161.25 and 167-174.5 c 170.75.
>>> >
>>> > About D-band: I am not sure what is precisely a 'D band' and I think
>>> > that discussion about bands is very complicated. I know there is
>>> > wikipedia page about it, yes.
>>> >
>>> > A person on twitter seems to be saying this filing is precisely the
>>> > filing that spacex did at FCC; but comparing the numbers shows some
>>> > differences: total sats per plane differ at some altitudes like at 
>>> 525km
>>> > altitude: ITU says 3600 sats whereas FCC says 3360 sats. There can be
>>> > speculations as to why they differ as there can be errors of various
>>> > people including myself.
>>> >
>>> > The person on twitter tells that ITU filing is in this table, but 
>>> I dont
>>> > know how he generated it. Not sure whether he made some syntax error.
>>> >
>>> >> Altitude (km) Inclination (degrees) Satellites per Plane Planes
>>> >> Total Satellites
>>> >> 340 53 110 48 5280
>>> >> 345 46 110 48 5280
>>> >> 350 38 110 48 5280
>>> >> 360 96.9 120 30 3600
>>> >> 525 53 120 28 3600 [nota by me: FCC says 3360 and not 3600, see
>>> >> table below]
>>> >> 530 43 120 28 3600
>>> >> 535 33 120 28 3600
>>> >> 604 148 12 12 144
>>> >> 614 115.7 18 18 324
>>> >>
>>> >
>>> > I found this earlier FCC document has this table at this URL
>>> > https://docs.fcc.gov/public/attachments/FCC-22-91A1.pdf (not sure
>>> > whether it is the most authoritative, but at least the mathematics
>>> > 28*120 at altitude 525 does make sense to be 3360).
>>> >
>>> >> Altitude (km) Inclination (degrees) Orbital Planes sats/plane 
>>> Total sats
>>> >>
>>> >> 340 53 48 110 5280
>>> >>
>>> >> 345 46 48 110 5280
>>> >>
>>> >> 350 38 48 110 5280
>>> >>
>>> >> 360 96.9 30 120 3600
>>> >>
>>> >> 525 53 28 120 3360 [nota by me:
>>> >> 28*120 == 3360 indeed]
>>> >>
>>> >> 530 43 28 120 3360
>>> >>
>>> >> 535 33 28 120 3360
>>> >>
>>> >> 604 148 12 12 144
>>> >>
>>> >> 614 115.7 18 18 324
>>> >>
>>> >
>>> > Alex
>>> >
>>> >
>>> > Le 16/11/2023 à 10:30, Alexandre Petrescu via Starlink a écrit :
>>> >>
>>> >> Le 15/11/2023 à 16:48, David Fernández via Starlink a écrit :
>>> >>> I have got news about the recent filing by Starlink for the use of
>>> >>> frequencies in D-band:
>>> >>> 
>>> https://www.itu.int/ITU-R/space/asreceived/Publication/DisplayPublication/53068
>>> >>>
>>> >>>
>>> >>> This has been done via Tonga, not the USA, and is for both, 
>>> uplink and
>>> >>> downlink frequencies, although only downlink seems to be 
>>> allocated now
>>> >>> for satellite use.
>>> >>
>>> >> Thanks for the pointer.
>>> >>
>>> >> It is the first time I hear about this 'ESIAFI II' constellation. I
>>> >> understand it is a different thing than the starlink existing
>>> >> constellation.
>>> >>
>>> >> It adds to the list of plans of LEO Internet constellations 
>>> (starlink,
>>> >> kuiper, oneweb etc.)
>>> >>
>>> >> Alex
>>> >>
>>> >>>
>>> >>> Regards,
>>> >>>
>>> >>> David
>>> _______________________________________________
>>> Starlink mailing list
>>> Starlink at lists.bufferbloat.net
>>> https://lists.bufferbloat.net/listinfo/starlink
>> -- 
>> ****************************************************************
>> Dr. Ulrich Speidel
>>
>> School of Computer Science
>>
>> Room 303S.594 (City Campus)
>>
>> The University of Auckland
>> u.speidel at auckland.ac.nz  
>> http://www.cs.auckland.ac.nz/~ulrich/
>> ****************************************************************
>>
>>
>>
> -- 
> ****************************************************************
> Dr. Ulrich Speidel
>
> School of Computer Science
>
> Room 303S.594 (City Campus)
>
> The University of Auckland
> u.speidel at auckland.ac.nz  
> http://www.cs.auckland.ac.nz/~ulrich/
> ****************************************************************
>
>
>
>
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