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The article isn't very clear but this seems to be standard fixed IoT device using a mobile SIM card is able to communicate via Starlink's mobile support.

Not sure why this is news. Starlink is known to be rolling out mobile support to certain regions. Due to spectrum licencing this is working with local telcos not a Starlink retailed service.

Does this type of satellite link provide the operator with the ability to derive fine grained location data the way the terrestrial cell network does? If not, would using such a network provide a significant increase in end user privacy?

I assume no. Regular Starlink beams are 15 miles wide. I don't know if DTC uses the same size or wider beams.

Yes but its not just about the beam. Signal timing can be used for more precise location. Even with one sat receiving the signal. Because they move so fast, much faster than the user could possibly move. So it basically could triangulate with itself as the other receivers. And there's also Doppler like the other poster mentioned.

I don't know if they actually do this, I guess not. And it would not be simple to do. But I'm sure it can be done. There's enough information available.

Starlink by the nature of how it works, knows exactly where receivers are. Perhaps even more accurately than GPS.

Are you sure? I know the dish needs to know where the satellite is, but that doesn't mean the satellite needs to know where the dish is...

The satellites do beam forming to target the dishes. For this, the dishes communicate their location, calculated from the satellite signals in essentially the same manner as GPS, to the satellites.

I don't think that's how it works. The beams appear to be fixed and thus they wouldn't need to know terminal locations.

They definitely appear to use beamforming internally. It appears that the satellite uses knowledge of receiver location (or at least receiver density) to select beamforming codebooks.

It's less likely they use this in their mobile coverage, but for their own terminals this is absolutely a thing.

https://people.engineering.osu.edu/media/document/2022-10-12...

They definitely do beamforming, but it's for tracking the stationary service cells as they pass overhead. You can see them represented in the illustrations in that paper.

Riffing a little bit after skimming this paper that was published a few years ago: https://radionavlab.ae.utexas.edu/wp-content/uploads/starlin.... Apologies for the acronyms, I'm going to do my best to remember to define them.

The SVs (space segment/satellites) in LEO (low-earth orbit) are going to be moving across the sky quite quickly relative to each GT (ground terminal). This is going to be inducing a pretty significant Doppler shift on the signals. Most of the linked paper is focusing on doing ground-based positioning, using the Starlink constellation as a GNSS-type source and talks specifically about how the Doppler shift at the ground is significant enough that not only does the carrier frequency need to track the Doppler shift but also that the baseband signal will be compressed/dilated.

For the SV, though, the same effect is going to happen. The GT is going to be transmitting back to the SV and the SV's going to need to do Doppler compensation in order to successfully decode the OFDM (orthogonal frequency-division multiplexing) signals from the GT. Throughout a pass, each GT is going to have a different Doppler signature based on its position on the ground relative to the SV. The SVs also need to know their positions in orbit with a high degree of accuracy, especially if they've turned on the SV-to-SV laser-based communication (not sure on that). By taking the SV's known trajectory and the per-GT Doppler measurements and making a couple of assumptions (e.g. GTs are stationary), I'm 99% sure you could solve a maximum-likelihood position for each of the GTs. I think you could do it with a single SV but if you have multiple SVs collaborating on it I suspect you could get a quite accurate solution very quickly.

Edit: one other thought I had while writing that up. If they designed the constellation to work this way, I also think it would be possible for the GTs to pre-compensate for the Doppler shift before transmitting, but I don't think I've ever heard of anyone actually doing that. The tradeoff there is GT transmit complexity vs SV receive complexity. I would love if someone pointed out an example of a system that actually does this, but I've only ever worked with systems that just use something like a PLL/Costas loop to track the Doppler shift without needing to estimate it directly. If they did do pre-correction it would definitely make it harder for the SVs to estimate the GT positions. It would make the GTs significantly more complex though and I would seriously doubt that Starlink would go through that effort to make the GTs more expensive and eliminate the ability to identify where they are on the ground.

I don't think pre-compensation would help here. There's multiple SVs in range at any given time so it's just correlating a shifting frequency signal instead of a fixed signal. Provided sufficient difference in the skew between SVs that should be quite trivial.

Anyway thanks. That definitely answers my question. If anything I'd expect GT location data to be more accurate than the terrestrial cell network, at least if the operator bothers to derive it.

They're not fixed, the sats move around the whole earth in around an hour or two so what the beams 'see' changes constantly.

Are you sure the dishes don't just have GPS on them? I have no idea either way, it just sounds like a GPS receiver would be simpler.

The user terminals use both; there’s a switch to enable the user terminal to ignore GPS if it’s inaccurate (for example in conflict areas where it is often spoofed or denied).

A good GPS receiver is quite complex. But it happens to be a commodity that has been well-optimized over the years.

Fair enough.

Would you care to elaborate? I thought GPS required diffing extremely high resolution clock signals. Meanwhile 5G has beam steering.

Elon said they could use the sats to make a GPS like service in the future, it’s just not a priority right now.

It it actually using starlink or the old swarm.space system that supported 'off the shelf' antenna

Swarm used pretty big antennas (due to a much lower wavelength) on the ground segment. It was pretty impractical. And that frequency, starlink sats are not capable of it.

Swarm's network was very incomplete, there were hours of no coverage at all. I think that they just bought it to remove a potential competitor.

Good question, I imagine its using m2m 4g if its "off the shelf"

monitor beehives in remote areas

The European honey bee is not a native species in New Zealand or Australia. Well meaning naive people think hosting bees is a great idea. The reality is it robs the native insect population of a food source.

It's more complex than that. That's like saying planting a garden robs the local ecosystem. Maybe! Maybe not!

Native pollinators have different life cycles and different plants they evolved to get food from. Honeybees, likewise, will only visit some flowering plants. That may increase competition for scarce resources, or it may not.

You are correct that honeybees are non-native, and that honeybees do draw a few lbs of nectar and pollen every day from the environment (up to a 3 mile radius from their hive), but it's unclear how much of that nectar and pollen is surplus from the plants or removed such that local bees experience pressure.

Planting a garden does rob the local ecosystem. Even purely native gardens lack the diversity, in particular mycodiversity, of undisturbed areas. While long term native planting can move an area back toward endemic biodiversity, it is rarely or never achieved (I'm not aware of any well-cited claims to the contrary).

It is similarly naive to view the introduction of a species through the lens of pollen quantity being 'surplus' or 'enough'. The presence of rival pollinators affects native insects whether or not there is a shortage of food - for example by discouraging presence, by occupying nesting sites, by altering endemic predation webs, and similar.

Weird. I tore up my lawn and replaced with wildflowers, native perennials, deep mulch from local leaf litter, and a small vegetable plot. I don't think I robbed the local ecosystem in the slightest. In fact, I'm fairly confident I did the opposite. But you seem convinced it's axiomatic that planting a garden robs the local ecosystem...

So you won’t even be able to isolate devices to your home network anymore, they will be phoning home by satellite

That's already possible, it's just expensive. Remember when the kindles[1] used to have the option for built-in 2G/3G connectivity "for life" to download books from Amazon that you never had to sign up for or maintain or pay for. Until networks dropped support for 2G and 3G in 2021.

[1] https://www.amazon.com/gp/help/customer/display.html?nodeId=...

I've explicitly bought all my Kindles with that feature. Amazon cheaped out a few years ago and it barely works on my 3rd Gen Oasis, which uses LTE

For small amounts of data transmit only you can do LoRawan with The Things Network for free.

Network map:

https://ttnmapper.org/heatmap/

So that started out as unlimited. After people abused it to tether it got dropped to like 50mb of non amazon traffic a month.

I think more worrying is devices mesh networking with devices owned by your neighbors.

Exactly, like Amazon sidewalk. They market it as an easy configuration feature but it can also be used for tracking and telemetry. So your smart TV can call home even when you don't connect your own WiFi.

I'm sure this costs money to use, just like regular cell service would for the same theoretical IoT device. That's probably the main barrier to having its own network.

Phoning home with a few packets here and there via the cell network is quite cheap. An adversary, pardon I mean OEM, doesn't need to upload 4k video to gain value here.

I mean, if you're looking to spy on or attack someone with wealth it's probably well worth it for some organizations.

I'm pretty sure it doesn't work indoors.

Regular companies are gonna need SCIFs.

It won't work very well indoors anyway. If at all.

Amazon sidewalk is a much bigger threat in this regard. I'm really glad we don't have this in Europe.

Never mind corporations, your next 'smart TV' will need a SCIF.

Arguably all your IoT devices already do. There were multiple startups advertising "routing at the edge" or some other such bullshit maybe ~5 years ago. I have no idea what happened with those ventures but these days multiple ISPs offer the general public roaming WiFi access via the APs of their customers so I think it's safe to say that ship has long since sailed.

Come to think of it how cheap are LoRaWAN radios these days? That's another option.

My custom home, if I ever build one myself, is going to be a faraday cage.

Future homes will have built in Faraday cages.

If you've got stucco siding and radiant insulation in your attic, you've got the home of the future.

Stucco is not conductive? So it wouldn't work as a signal blocker

Stucco itself is not conductive, but it's usually applied on a base of metal mesh (similar to chicken wire, but apparently actual chicken wire isn't appropriate). Some projects use fiberglass mesh as the lath, and some may use traditional wood lath, but my understanding is the majority of stucco for house construction uses metal wire mesh for the lath.

Awesome insight.

If anyone walks past your house with a device in the same bluetooth p2p network as your device this is already true (Amazon sidewalk). This could give them a more uninterrupted connection though.

I think these e.g. Verizon guest wifi:s might be used to try to spy on us too.

More scrap parts for Russian drones.