[Starlink] Starlink filings for D-Band via Tonga

Thu Dec 21 04:45:27 EST 2023

There is no overlap between 117.975-137 MHz and 123 - 130GHz.

D-Band will work much better for links on aircraft flying above
clouds, less attenuation.

> Date: Tue, 19 Dec 2023 18:27:19 +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: <cd0f2602-9ce6-4b8e-94e4-481493e7a3c2 at gmail.com>
> Content-Type: text/plain; charset=UTF-8; format=flowed
>
> Today I learn that 117.975-137 MHz is considered at ITU for aviation and
> satellite [*].
>
> Note that range overlaps with 'ESSAFI's 123 - 130GHz.
>
> Maybe it is for that purpose - in-flight entertainment(?) that starlink
> requested the D-band frequencies, and not for sat-sat nor sat-gnd.
>
> Alex
>
> [*]
>
> "Allocation of new frequencies to the aviation industry for aeronautical
> mobile satellite services (117.975-137 MHz). The new service will
> enhance bi-directional communication via non-GSO satellite systems for
> pilots and air traffic controllers everywhere, especially over oceanic
> and remote areas."
>
> text quote from this URL at ITU:
>
> https://www.itu.int/en/mediacentre/Pages/PR-2023-12-15-WRC23-closing-ceremony.aspx?utm_source=ITU+News+Newsletter&utm_campaign=c66517f297-EMAIL_CAMPAIGN_19_12_2023_ITU-NEWSLETTER&utm_medium=email&utm_term=0_-2f420cccc6-%5BLIST_EMAIL_ID%5D&ct=t(EMAIL_CAMPAIGN_19_12_2023_ITU-NEWSLETTER_INT)&mc_cid=c66517f297&mc_eid=3ca8d7193e
>
> Le 06/12/2023 à 13:02, Alexandre Petrescu via Starlink a écrit :
>> In another context someone pointed me to spacex saying 'D-band' in
>> april 2023 in this "NTIA Docket No. 230308-0068 / Docket
>> NTIA-2023-0003"
>> https://www.ntia.gov/sites/default/files/publications/spacex.pdf
>>
>> From that text, I understand it would, or could, be for sat-to-gnd.
>>
>> Le 23/11/2023 à 14:40, Alexandre Petrescu via Starlink a écrit :
>>>
>>> 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/
>>>>> ****************************************************************