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The article doesn't mention which satellites or which satellite provider is used. But Apple invested $450 million in Globalstar.

https://www.apple.com/newsroom/2022/11/emergency-sos-via-sat...

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This article from LeMonde seems to imply that they're using Globalstar:

> "To offer this new feature, Apple had to integrate a miniature antenna in its smartphone. It captures part of the signal of satellite constellations without relying on a satellite dish or a specific telephone handset. The iPhone manufacturer signed an agreement with Globalstar, one of the operators of low-altitude constellations, sets of satellites flying at about 500 kilometers from the Earth, in order to cover low-coverage areas of the globe. Specializing since 2007 in professional satellite messaging, Globalstar explained that it reached an agreement to launch 17 new satellites for 327 million dollars, 95% of which will be financed by Apple in exchange for 85% of their bandwidth."

https://www.lemonde.fr/en/economy/article/2022/09/13/apple-a...

The "85% of their bandwidth" part is super interesting. It implies usage for much more than occasional emergencies. Globalstar has ~12Mhz of global S-Band spectrum[0], which they describe as "3.7 Billion MHz-POP", a unit I'm not grokking.

But I am pretty sure that is a LOT more bandwidth than what will be used for highly compressed text messages in emergencies.

[0] https://www.globalstar.com/Globalstar/media/Globalstar/Downl...

A MHz-POP is just bandwidth times population covered by the Geographic Service Area (i.e., where the company is licensed to operate). For example, in the US, they would have 11.5 MHz x 330 M = 3.79 Billion MHz-POP.

Thank you! Doesn't that seem like a weird metric? I would think MHz/POP would make more sense. I guess the idea is to assume unlimited and independent channels to everyone as a first order?

I think multiplying by population serves as a way to normalize for link speed. Ten people who use a lot of spectrum are probably bigger customers than ten people who use a tiny sliver of spectrum, and thus constitute a bigger user base.

MHz-POP makes the most sense in cell networks, where an operator (AT&T, T-Mobile,...) wants to acquire a spectrum license in a particular region of the country. Evaluating the MHz-POP makes sense as the price they are willing to pay varies a lot depending on the population density in that region area. In general, cell networks can reuse spectrum more easily (deploy more towers, add more sectors), and they design their network deployment to hit whatever MHz/customer they are targeting (which mostly depends on the technology 3G/4G/5G).

In sat-networks, well, MHz-POP doesn't matter that much, because, generally, every operator is licensed to operate in the whole country. As you mentioned, what really matters is (a) the bandwidth of their license allocation (e.g., Globalstar is 11.5 MHz), and (b) how efficiently can they reuse spectrum:

* how many beams can they land (# satellite x # beams / satellite)?

* how much freedom do they have to chunk bandwidth and allocate it to individual beams based on demand?

* what type of satellite are they using, bent-pipe or regenerative payload?

* how big are these beams?

* can they allocate resources dynamically or is everything fixed?

* how much power does the satellite have? how big are the terminal antennas? what kind of link-budget can they close?

In the end, the MHz/customer they can achieve depends on the answer to all these questions.

I was really wondering what kind of satellite-based emergency SOS they were using -- mostly because I'd never heard of it until it was being shipped in a commercial product, which is something very rare to see.

So basically, they have their own infrastructure for their own proprietary 911 service with global coverage? It's really amazing that we live in a world where we can have such infrastructure, but at the same time, it's owned and controlled by a single corporation.

I notice there's multiple mentions of these satellites working with the "Find My" service, which keeps track of where a device is (in order to find it where it's lost). So I guess all this infrastructure also allows Apple to pinpoint down any user worldwide -- even if they're off-grid.

It's basically running on the same system as their current SPOT trackers in the S- and L-band. L-band up, S-band down.

Are you sure about that? I was under the impression that this was running on N53, which is towards the bottom of S band, both directions.

It's suppose to be on Globalstar's existing network which would be S-band and L-band but CDMA. It's not 5G-NR just yet though that's likely where they're headed.

I think Apple added n53 as part of this deal at Globalstar's request. Globalstar is trying to lease their spectrum terrestrially for small cell networks and network capacity solutions for the carriers.

https://www.globalstar.com/Globalstar/media/Globalstar/Downl... (PDF warning) Here's a presentation with some details.

https://fccid.io/BCG-E8140A

The "emission type" for the satellite service is 198KG1D and operates under FCC rule Part 25 (Satellite Communications). They run 400mW or so up on 1.6GHz L-band, and ~90mW downlink S-band.

https://fccid.io/L2V-PT3

A Spot Gen3 runs around 200mW on L-band only for both ways. There's a slightly different emissions type, but same satellites.

The ground stations had additional hardware added by Cobham to support Apple's use on L/S-band.

> So I guess all this infrastructure also allows Apple to pinpoint down any user worldwide -- even if they're off-grid.

Well, they could do that in the past - GPS works (almost) everywhere. They'd just have to wait with sending the data back.

Looks like it requires consciously deciding to share your location, and pointing your device where it tells you in the sky.

They’re not going to burn precious bandwidth on an always-active tracking thing.

>It's really amazing that we live in a world where we can have such infrastructure, but at the same time, it's owned and controlled by a single corporation.

I get this sentiment. Globalstar does have competitors at least. Iridium and Inmarsat offer comparable services though not as seamlessly integrated into a popular consumer device.

I do wonder what happens if you aren't paying for the service but have an emergency. I guess they just don't connect you at all? Is there an automatic charge for accessing it?

It's currently free (for the first two years after purchase of the device), and I suspect that while emergency SOS messaging will always remain free, they will add paid P2P messaging soon.

GPS has always been available to get location information even offline. What you usually don't get at the user end is a map of where you are because maps apps don't cache or download automatically. I've installed OSMAnd+ and downloaded a lot of maps to avoid that and I wish Google Maps or Apple Maps made it easier to download a large swath like you can with OSM. (you can even download POI to still be able to do some searching for places if you don't have an actual address)

As for infrastructure I think Verizon is doing something similar with Starlink and there are multiple possible satellite constellations that could be connected too Apple is just the first to include what I think has to be a new radio or radio component.

I believe it is T-Mobile and Starlink, though very early stage (just a press release[0] about "a vision to give customers a crucial additional layer of connectivity" that "aims to work" with existing phones, far as I can tell).

And yes, the Apple announcement is just the productization of a feature in the Qualcomm X65[1]. But I think this is a case where the technical implementation is the easiest part; I would be surprised of other X65 adopters also delivered satellite comms, at least unless/until it's obvious it's driving phone purchasing decisions.

[0] https://www.t-mobile.com/news/un-carrier/t-mobile-takes-cove...

[1] https://9to5mac.com/2022/09/18/iphone-14-satellite-connectiv...

I think it depends massively on how much it costs the company to provide. If it's just a chip and a bit more software I think companies will include it. It's not clear from the press reports if the money Apple spent on building up base stations for this are just for them or if the satellite providers could use them for other companies phones.

Knowing Qualcomm, there's probably a major royalty cost involved.

If Apple spends $450 million to enable the service [0], that's about $2 per phone sold in 2021 [1].

[0] https://www.cnbc.com/2022/11/10/apple-spending-450-million-w...

[1] https://www.bloomberg.com/news/articles/2022-08-11/apple-exp...

"Band n53" has been widely reported in the context of various iPhone satellite rumors, but I still believe that this was actually just bad reporting: Band n53 is essentially terrestrial LTE/5G usage of Globalstar's global spectrum rights in a band that was previously designated for ground-to-space usage.

Whatever the iPhone 14 is using to talk to the Globalstar satellites, I'd be extremely surprised if it looked anything like LTE or 5G at the physical or logical layer.

[1] https://investors.globalstar.com/news-releases/news-release-...

I remember reading that they are in fact using n53 2.4Ghz. Remember this is a fallback for areas without cell service, and a satellite signal is much weaker on the ground than any terrestrial signal.

Given that it's a two-way service, and Globalstar satellites use the 2480-2500 MHz range for downlink transmissions, it must be using 2.4 GHz, yes.

But my point is that this probably has very little to do with Globalstar's terrestrial band 53 efforts, other than possibly sharing some HF hardware in the new iPhones given that they support both that terrestrial LTE/5G band and satellite messaging.

> I wish Google Maps or Apple Maps made it easier to download a large swath like you can with OSM.

Google Maps on iOS let’s you choose squares on the planet and download offline maps.

Open the app, click your initial at the top right and you’ll see Offline Maps in the drop-down.

Driving directions only though. But you can search for POIs and it will navigate you there. Or you can look at the maps/streets.

I use it regularly in USA and Europe when I don’t have a data plan there. Or when I’m low/out of data in Canada because Canadian telecom sucks. Or when Rogers shits the bed.

I also have Kiwix with full copies of Wikipedia (about 85gb) and a few other resources. And a small solar panel so when doomsday hits…

Yeah I've used that in the past on Android and it's been very sketchy. The app will seemingly let the map expire and if I don't remember to check every time I go up to the mountains where I need it I'll usually get stuck without a working up to date map. It also doesn't seem to hold that many POI locations so I'm stuck just navigating to the right town and hoping I get signal eventually to find the actual place I'm going. OSMAnd+ however just keeps the data even if it's older so I'll always have at least some street data.

The maps used to expire after 30 days, but is now 365 days. I agree: it’s arbitrary and unnecessary.

It does background refresh but unsure how great it is. Right know my maps expire with different dates between July and November 2023, so I guess it’s keeping up to date enough.

Maybe it's better now I have haven't travelled much this year and after downloading the OSM data I haven't bothered with offline google maps because I have all the roads and more already.

With OSMAND you just dl provinces/states from a menu and it's done.

Anyone know performance wise between Garmin's use of Iridium and Globalstar?

Iridium has been around for soo long...I am getting constant outages from the status page. Kind of disconcerting at times.

Ah, I found the following article that somewhat explains the different technologies w/

"The main difference between Iridium and Globalstar is the relaying mechanism. Iridium requires relaying between satellites. Globalstar requires relaying between satellites and earth stations."

https://www.mobilsat.com/the-best-satellite-phone-globalstar...

in non-dollar terms:

Apple is paying for 95% of Globalstar's new satellites and plans to use 85% of their network capacity.

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