[CalFiber] Fiber Broadband Association study on the capacity limits of Starlink

Ernesto Falcon ernesto at eff.org
Fri Mar 5 11:39:48 PST 2021


My prediction as to why its 4,

Each spot beam takes up real estate on the satellite via an antennae, so that 4 limit is probably a physical space challenge (plus weight). Antenna lengths are controlled by the frequency you use to transmit, though a lot of smart engineering has made it where it doesn’t have to be a straight antenna like an old school radio. But they can’t just make smaller antennas because this is baked in physics, they have to figure out how to configure it where it can use the frequencies they are assigned in more clever ways like how smart phones wrap it around the handheld. And technological advancements will have to wait till a large part of the satellite fleet is retired as old ones are cycled out new ones every handful of years.

Satellite TV has this same challenge with local broadcast channels. Each satellite can only cover so many local markets because of the number of spot beams each can hold. They have to keep the old satellites going for years until they get decommissioned and replaced by a new satellite with new advancements in spot beam tech, so you have lags where you have satellite TV being transmitted in 2021 with 2016 tech. Unlike broadband, satellite TV advancements came with more efficient compression of TV stream distribution, so essentially using less data to achieve the same results, which meant fewer spot beams can cover more area with the same capacity. I don’t think that option is available for download/uploads.

Unrelated but interesting note about Starlink. One of my friends who is beta testing now sent me some updates. It’s a solid 100/15 mbps, which is great as a basic service. But the thing I didn’t account for but makes sense is his Internet goes out at set intervals for about 15 seconds. That’s the delay between one satellite passing over his connection then losing line of sight and the next satellite coming to pick up the connection. That’ll be fixed with more satellites to ensure there isn’t a break of line of sight, but basically non-live streaming Internet activity is a non-starter but Internet activities that can buffer work great. Just delivering consistent connectivity adds costs to Starlink via more rocket launches before we even get to increasing capacity.

From: Christopher Mitchell <christopher at ilsr.org>
Date: Friday, March 5, 2021 at 11:01 AM
To: Ernesto Falcon <ernesto at eff.org>
Cc: calfiber at lists.eff.org <calfiber at lists.eff.org>
Subject: Re: [CalFiber] Fiber Broadband Association study on the capacity limits of Starlink
Someone more technical than me can correct me but I think the spectrum limitation is per spot beam and they told me that they don't think they are limited to 4 spot beams per satellite. Each spot beam is 5 gbps I think. Currently they have 4 spot beams per satellite I think.

On Thu, Mar 4, 2021, 4:54 PM Ernesto Falcon <ernesto at eff.org<mailto:ernesto at eff.org>> wrote:
Other than more spectrum or more satellites, I am not sure there is another realistic way to have the kind of doubling of capacity in the satellite system to stay ahead of trends in consumption. We see that with cell towers now where its densification or more auctions. And the doubling of consumption every handful of years is a recorded trend that isn’t changed yet, so I don’t think the 20-30% estimate is bad assumption here on what to predict.


--
Ernesto Omar Falcon
Senior Legislative Counsel
Electronic Frontier Foundation
Office: 415 436 9333 ext. 182
Cell: 202 716 0770

From: Christopher Mitchell <christopher at ilsr.org<mailto:christopher at ilsr.org>>
Sent: Thursday, March 4, 2021 2:14 PM
To: Ernesto Falcon <ernesto at eff.org<mailto:ernesto at eff.org>>
Cc: calfiber at lists.eff.org<mailto:calfiber at lists.eff.org>
Subject: Re: [CalFiber] Fiber Broadband Association study on the capacity limits of Starlink

I mentioned this on the call I think some time ago... I don't think the assumptions are very credible. It may be that Starlink will have problems, but I don't think the Starlink folks expect to have the limitations that this analysis assumes, like the max capacity per satellite.

I'm not taking a position on whether Starlink should be subsidized and I damn sure hate the way it is subsidized today - it harms some rural folks much more than others.

Christopher Mitchell
Director, Community Broadband Networks
Institute for Local Self-Reliance

MuniNetworks.org<http://www.muninetworks.org/>
@communitynets
612-545-5185


On Thu, Mar 4, 2021 at 2:47 PM Ernesto Falcon <ernesto at eff.org<mailto:ernesto at eff.org>> wrote:
This just came across my desk and was filed at the FCC earlier.

It projects that by 2028 Starlink’s capacity will start to hit its limits when measured against 20-30% annual growth in consumption needs, which sounds right to me. It is this question of whether your network has the capacity to stay ahead of the demand curve for the long run is why I wrote this piece (https://www.eff.org/deeplinks/2020/06/why-slow-networks-really-cost-more-fiber) since often the slower capacity constrained providers will argue that they are cheaper than fiber so give them the tax money to build.

This is part of the larger fight over whether the federal government should be subsidizing Starlink at all.

--
Ernesto Omar Falcon
Senior Legislative Counsel
Electronic Frontier Foundation
Office: 415 436 9333 ext. 182
Cell: 202 716 0770

_______________________________________________
CalFiber mailing list
CalFiber at lists.eff.org<mailto:CalFiber at lists.eff.org>
https://lists.eff.org/mailman/listinfo/calfiber
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.eff.org/pipermail/calfiber/attachments/20210305/4fe53197/attachment-0001.html>


More information about the CalFiber mailing list