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> Lost interest when I read: > >The test location had a rocky desert topology with minimal foliage, and tests were conducted using LTE Band 41 (2,500 MHz).

Testing was conducted in other locations as well. One use-case being discussed doesn't exclude the others.

For example:

> The Metcalf location has flat terrain with thick deciduous trees covering the land.

Also...

> Ignoring all the other social/anticompetitive issues there is with Facebook proposing this, it stinks like a scam to get a tax writeoff or jump onto the same sort of FCC rural internet grant money Starlink is bilking taxpayers out of.

Facebook doesn't build and operate this kind of network. This project (and others such as efforts in middle mile fiber construction and funding cable consortiums) are largely intended to help regional carriers outside of the US past hurdles around capacity and density that limit their growth. Since it's not targeted at the US, the FCC's grants, spectrum allocation, and power limits are not relevant.

Cui bono?

Facebook's learned that just getting people connected to the internet in a content-agnostic way is sufficient for growth. This is why FB funds consortium fiber around and across Africa, funds internet exchanges, and makes free network planning tools available to carriers.

https://www.internetsociety.org/issues/ixps/facebook-ixp-par...

Disclaimer: I'm a Network PE at Facebook, in prod, not in connectivity labs where this project originated, and def not speaking for the company.

> Testing was conducted in other locations as well. One use-case being discussed doesn't exclude the others.

Except the comment you're responding to doesn't seem to take issue with the location. It goes on at some length about the problems with LTE Band 41.

How does pointing out that testing occurred in other locations address the problems with Band 41?

>Ignoring all the other social/anticompetitive issues there is with Facebook proposing this, it stinks like a scam to get a tax writeoff or jump onto the same sort of FCC rural internet grant money Starlink is bilking taxpayers out of. You can't scale a midband macro like this even using a dumb amount of spectrum. Oh totally forgot, there's an 'educational' use case for use of BRS (2500mhz) spectrum that I'll bet Facebook will also try to get their hands on.

Is it very clear that this pessimism/cynicism is warranted?

https://www.youtube.com/watch?v=XzXZdipxCuw

>Is it very clear that this pessimism/cynicism is warranted?

Yes, read some of my earlier comments regarding Starlink, DISH, and general telecom schemes. I'm not coming out of nowhere with this criticism.

With that being said I fully understand where their system is better than current MEO/GEO systems for low-latency rural deploys. I'm just not in the cult of Elon, physics/money/practicality have their limits.

I'd honestly be more excited with Starlink if they were primarily using it as a replacement for satellite backhaul on very remote cell sites. That way you don't need residential roof antennas and a ton of power to communicate with the network, just need your main power at the cell site. That's more practical for poor rural countries but isn't as big of a writeoff, doesn't look as sexy.

I could see Starlink-fed WISPs or cellular becoming something very real. Starlink CPE is very expensive and probably heavily subsidized. Plenty of villages where 0 can afford it, but collectively they could.

Starlink may as well take the money on the table if the constellation will fly overhead anyway.

This is the business model that Telesat trying to make work. While they are behind Starlink in terms of rollout, they are a credible manufacturer/provider for a service like this

https://www.canwisp.ca/resources/Conference%202020/Presentat...

I take all that to mean that Telesat hasn’t cracked the $$$ CPE nut like SpaceX has, or the SpaceX CPE subsidies are even bigger than I can imagine.

Small point, but the idea here is not using additional spectrum, the antenna design lends (in their analysis) up 29dB added link budget. For a more intuitive example, that's roughly the equivalent of pointing a satellite dish at your phone.

>This is why in urban areas it usually makes more sense to use cell network to save battery

Hmm. Rhen why does Apple recommend using WiFi for power saving?

“When you use your device to access data, a Wi‑Fi connection uses less power than a cellular network”

https://www.apple.com/batteries/maximizing-performance/

There's a lot of confounding factors, but in general: Cell network uses very little power when idle, but a lot when transmitting. Wifi on the other hand uses a medium amount of power when idle, and a medium amount when transmitting. (this is really generalized and there have been a lot of recent advancements to optimize power usage of both).

This is why general guidance for years was to use wifi when you are actually using your phone for browsing the internet, taking advantage of wifi's lower power efficiency when in use, but to turn off wifi when your phone is just in your pocket/idle to take advantage of cell network's better idle power efficiency.

However, the above is really only true for urban/suburban areas where you have good signal. If you are in an area with poor signal, your phone will use a lot of battery power via the cell network even when "idle" (because in reality even though your phone is "idle", the cell radio isn't actually idle, it's constantly struggling in the background to maintain the connection through the poor signal).

Just adding onto your comment, Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap. 2. The wifi chipsets they use are basically their own self-contained computers that can manage scanning at low-power without taxing the CPU. 3. At least for new HW, some of the 5G-NR stuff really isn't well optimized yet, not as bad as LTE originally was... but it's entirely possible the new modems for now are a little power hungry. Turning on wifi makes the cell chipset track less carriers, typically it'll just hug to one low-band carrier for status/push messages instead of as many as 5 or 6 carriers.

EDIT: Phones usually only transmit on one channel while receiving anywhere from 1-7 different channels at once, only the recent flagships transmit on 2 or 3 right now.

> Apple probably recommends use of wifi because: 1. They collect AP's for their mapping/location crap.

Nope. And the reason this is obvious is because turning off WiFi via the control center doesn’t actually turn off WiFi so collecting SSIDs wouldn’t be a problem either way.

This sounds like an appropriate test for equipment deployed into large areas of Africa, Central Asia and the Middle East where T-Mobile/Sprint don't operate.

I don't think the problem is the companies but the band itself, which follows physical laws. GP has experience with the limits of this band because it's used by Sprint/T-Mobile.

Sure, but perhaps it's an improvement on any existing coverage options or even a lack of any.

I just don't buy it.

One way to make a system like this work is heavily proxy and strip rich media out of the network (Globalstar sells a device called the SatFi that does this for their MEO constellation, Opera Mini used to do it for featurephones), so you can support quality of service in a remote population.

There's a financial incentive for Facebook to provide access to a specially crafted 'walled garden' that's designed for lower bandwidth scenarios. Facebook has tried this shit before in India without touting special network hardware and it was not well received: https://www.cnet.com/news/facebooks-free-basics-internet-ser...

Yup, this is exactly "Free Basics” reloaded. Fortunately their sat blew up in their face and then Jio erased any competitive advantage they might have had in India.

But given that way more Indians now have data, I'm not sure that it's much of a loss to Facebook, as they got the users.

They dont have buildings there? or no trees?

Are you excited for Starlink, or will line of sight be a problem for that?

So long as you don't live in a crater or have skyscrapers blocking your view line of sight should not be an issue for a majority of the population. Starlink wouldn't require a specific southern view of the sky like a GEO system does but it won't do well in 'urban canyons'. MEO consumer things you might be familiar with that experience reduced signal in the described conditions include GNSS (GPS) and SiriusXM.

Starlink is not meant for densly populated areas where 'urban canyons' as you called them would be found. The bandwidth of the simultaneously reachable satellites is basically constant everywhere, except at higher latitudes where satellites on different orbital planes get closer to each. So distributed users are preferred to lots of users in a single place, since the latter would have to share the bandwidth while the same number of distributed users would access via different satellites instead and would see an increased total bandwidth available.

Look at the graph on "population and satellite density per degree" in [0] to see why SpaceX has most likely chosen the inclination that they use.

[0] https://caseyhandmer.wordpress.com/2019/11/02/starlink-is-a-...

Sirius is now GEO, but has ground repeaters in problem areas.

GPS has the advantage of seeing multiple satellites and working with that by design since its one way. Despite that, Japan launched its own satellite to supplement GPS because it had so many issues. I think we’re spoiled by our phones that supplement GPS with cellular signals, wifi and inertial references.

The newest phones actually even do dual-frequency GPS using a newer signal (L5). It's accurate enough to do lane-keeping.

Existing systems also supplement GPS network data with russia's GLONASS, as well as sometimes WAAS if the satellite gets picked up (WAAS is GEO system to provide for additional accuracy, since it's further and requires a path facing south, it's not often picked up on phones)

>Inertial reference

Can we really do inertial reference with current phone hardware? I would imagine our usecases don't really even give inertial reference a nice playing field.

>Can we really do inertial reference with current phone hardware?

Yes, check the specs for any recent (past 3 years) qualcomm chipset, initia sensors will be included. You can play around with this sensor (and others) using the Phyphox app for ios and android.

Maybe my terminology isn’t ideal, but I figured my NAV apps can tell I’m doing things like a U-Turn based on G-forces. But maybe it’s just using its compass.

My old Garmin wouldn’t realize I did a u-turn until I have half way back down the street.

I'm excited about the quantum teleportation fermilab has been making progress with, but I don't know if line of sight will be a problem for that either.