From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from oxalide-smtp-out.extra.cea.fr (oxalide-smtp-out.extra.cea.fr [132.168.224.13]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id E0E673B2A4 for ; Thu, 21 Dec 2023 05:25:03 -0500 (EST) Received: from pisaure.intra.cea.fr (pisaure.intra.cea.fr [132.166.88.21]) by oxalide-sys.extra.cea.fr (8.14.7/8.14.7/CEAnet-Internet-out-4.0) with ESMTP id 3BLAP2Me051434 for ; Thu, 21 Dec 2023 11:25:02 +0100 Received: from pisaure.intra.cea.fr (localhost [127.0.0.1]) by localhost (Postfix) with SMTP id 3B2842068E0 for ; Thu, 21 Dec 2023 11:25:02 +0100 (CET) Received: from muguet1-smtp-out.intra.cea.fr (muguet1-smtp-out.intra.cea.fr [132.166.192.12]) by pisaure.intra.cea.fr (Postfix) with ESMTP id 341DF2068A7 for ; Thu, 21 Dec 2023 11:25:02 +0100 (CET) Received: from [10.11.241.150] ([10.11.241.150]) by muguet1-sys.intra.cea.fr (8.14.7/8.14.7/CEAnet-Internet-out-4.0) with ESMTP id 3BLAP2bP029139 for ; Thu, 21 Dec 2023 11:25:02 +0100 Message-ID: <24bd3828-253c-492c-9bbc-371823812862@gmail.com> Date: Thu, 21 Dec 2023 11:25:01 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: fr To: starlink@lists.bufferbloat.net References: From: Alexandre Petrescu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CEA-Virus: SOPHOS_SAVI_ERROR_OLD_VIRUS_DATA Subject: Re: [Starlink] Starlink filings for D-Band via Tonga X-BeenThere: starlink@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Starlink has bufferbloat. Bad." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Dec 2023 10:25:04 -0000 overlap: sorry! it is indeed MHz and not GHz, I overlooked that. But the 117-137 _MHz_ bands are already used from ground to planes; the modernisations I have seen of it relate to automating the status voice bulletins, and maybe the use of IP over airbands.  Putting that on LEO sats, hmm, looks newer.  I am not an expert in that band. D-band better for airplanes above clouds: I agree with the theory. Alex Le 21/12/2023 à 10:45, David Fernández via Starlink a écrit : > 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 >> To: starlink@lists.bufferbloat.net >> Subject: Re: [Starlink] Starlink filings for D-Band via Tonga >> Message-ID: >> 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 >>>>>>>> To: starlink@lists.bufferbloat.net >>>>>>>> Subject: Re: [Starlink] Starlink filings for D-Band via Tonga >>>>>>>> Message-ID: <805d52ce-b517-49b9-a053-8306cd20b8aa@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@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@auckland.ac.nz http://www.cs.auckland.ac.nz/~ulrich/ >>>>>> **************************************************************** > _______________________________________________ > Starlink mailing list > Starlink@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/starlink