71–80 of 179 posts
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Galileo. Controlled by the EU, and therefore a better choice than GPS, since the United States is no longer trustworthy.
Honestly how trustworthy was the US before? Are we supposed to be completely fine with PRISM and XKeyscore now?
This system should be shutdown. What if enemies use it to guide their rockets?
If it’s not intrinsic to FM, why not use existing cellular towers to do this? They’re everywhere, and phones already receive broadcast messages (like Amber Alerts) even without a SIM (I think) — so it feels like this could be done without needing new radios.
What makes this more accurate than cell tower triangulation today? Is the limitation in timing sync across towers, or something else in how cell networks are structured?
And for indoor use — how does this handle multipath? Reflections from walls or even atmospheric bounce seem like they’d throw off timing accuracy, similar to what messes with GPS in dense areas.
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How does it solve for time without location? With GPS location and time are one solution to an equation with 4 unknowns (x,y,z,t). Without location you won't know the time delay between you and the transmitter.
The the transmitters are of fixed terrestrial locations.
I hope it will still be possible to receive a BPS timing signal privately and anonymously with ATSC 3 like one can with GPS. ATSC 3 has the Dedicated Return Channel because marketers “““need””” to spy on every-fucking-thing we do: https://www.atsc.org/wp-content/uploads/2024/04/A323-2024-04... “Conventional linear TV services alone (albeit ultra-high-definition) may not be sufficient to sustain the terrestrial broadc…
Just like 5G, which provides unexpected connectivity for IoT devices. Search for "miot" or "mmtc"
OP is falling about the spec incorporating usage monitoring.
5G was designed with a very public and explicit goal for IoT of allowing many more devices to connect than 4G could, and more conveniently. Nothing unexpected or user-harming, and nothing new as 4G was already used for IoT.
If planning/designing a timing system like this using existing antenna, why wouldn't you choose to use cellular base stations? The cellular network reaches most places with overlapping coverage and carries network time. The lowest cellular frequencies are adjacent the upper broadcast TV channels. Aren't modern cellular receivers what we call software defined radios? They can choose which channels to receive.
They use precise timing to coordinate timed broadcast slots between base stations with overlapping coverage.
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The the transmitters are of fixed terrestrial locations.
So you set your clock up by telling it its own location, so it can offset for the signal's flight time?
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A university of Texas research group demonstrated more than ten years ago that they could spoof GPS in the vicinity of an automatically navigating UAV, and force it to land at a point of their choosing. This has been within the reach of garage hackers for a long time.
Now the UAV needs to track where the signal is coming from. “Hey, this isn’t coming from the sky, what gives”
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So atsc 3 won't work unless you have some continuous "i'm user xyz watching this channel at time x.y.z" going back to the broadcaster? Why would anyone use atsc 3? It's not free over the air, you can't spoof it?
It's not like anyone's gonna ask them. Networks will just label this as ${network name}'s HYPER NEXT GEN 10G TV EXPERIENCE (HNG TV), market the shit out of it, and offer free ESPN on it, tack on some Paramount HBO Supermax Plus for $0.99/year and throw in a half-decent Smart TV as a sign-on bonus, and adoption will skyrocket. TV networks in the US are a living proof that, with enough marketing spend and a pinch of co…
That kind of pumping makes me sad and sick.
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The reason that dead reckoning was inaccurate was because of clock and vector inaccuracies. Looking at the advances in clockpieces and gyroscopes (both of these has benefitted over the optical revolution) over the years, I am not shocked that dead reckoning is back in vogue.
Dead reckoning is also inaccurate due to unknown winds. Even if you take off with the best available forecast, it’s often wrong by 5mph+. After three hours your position is off by 15 miles. That’s not remotely good enough for most aviation purposes.