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BPS is a GPS alternative that nobody's heard of

jeffgeerling.com

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Re: BPS is a GPS alternative that nobody's heard of

#51

Post by eMPee584 »

gblargg wrote: post #30
kristopolous wrote: post #24

Earlier quoted context omitted.

I'm fighting through a cold so granted my reading comprehension is way down but at least in my diminished state I was reading through that and was baffled ... I'm sure the average reader who deals with broadcast signal electronics knows what's going on here but I just walked away from it confused. It looks like terrestrial broadcasters sending out time codes for triangulation?

I was amazed to not even find a Wikipedia article about BPS.

quick, call in wiki support & take cover!

Re: BPS is a GPS alternative that nobody's heard of

#52

Post by cameldrv »

zinekeller wrote: post #47
typewithrhythm wrote: post #45

Earlier quoted context omitted.

You can't really beat a jammer, sure you can compete for power output, but there is no real stopping it. Aircraft and military positioning concepts are evolving towards more map and dead reckoning, lessening the benefit of GPS jamming.

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.

Re: BPS is a GPS alternative that nobody's heard of

#53

Post by dieselerator »

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.

Re: BPS is a GPS alternative that nobody's heard of

#54

Post by plextoria »

typewithrhythm wrote: post #45
lxgr wrote: post #21

High-power, and ideally authenticated, alternatives to space-based GNSS are desperately needed, given the sharp uptick in jamming and spoofing incidents in many places. In a true "end of history" moment, the US and other NATO members discontinued both of their ground-based systems (which are inherently harder to jam due to their much higher transmission power, since transmitters are not power limited) – Omega in the…

You can't really beat a jammer, sure you can compete for power output, but there is no real stopping it. Aircraft and military positioning concepts are evolving towards more map and dead reckoning, lessening the benefit of GPS jamming.

Correct me if I’m wrong, but wouldn’t a jammer be very easy to disable kinetically?

A missile would simply have to follow the jammer’s signal.

Re: BPS is a GPS alternative that nobody's heard of

#56

Post by fnordpiglet »

The_Double wrote: post #40
geerlingguy wrote: post #3

Note that this blog post (and the associated video) were a quick off-the-cuff thing while I was on the NAB show floor—I have been talking to a few of those involved in the testing at NIST, Sinclair, and Avateq (among others), and will hopefully have a lot more in a follow-up. Right now it's in the experimental stage, with only 6 towers total deployed (only 5 were operational during NAB, and only one in Nevada... so t…

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.

Re: BPS is a GPS alternative that nobody's heard of

#57

Post by fpoling »

typewithrhythm wrote: post #45
lxgr wrote: post #21

High-power, and ideally authenticated, alternatives to space-based GNSS are desperately needed, given the sharp uptick in jamming and spoofing incidents in many places. In a true "end of history" moment, the US and other NATO members discontinued both of their ground-based systems (which are inherently harder to jam due to their much higher transmission power, since transmitters are not power limited) – Omega in the…

You can't really beat a jammer, sure you can compete for power output, but there is no real stopping it. Aircraft and military positioning concepts are evolving towards more map and dead reckoning, lessening the benefit of GPS jamming.

Plus aircrafs can use Earth gravity map. Sensors became accurate enough to detect minuscule changes in gravity strength to position aircraft to few hundred meters.

Re: BPS is a GPS alternative that nobody's heard of

#58

Post by t0mas88 »

cameldrv wrote: post #52
zinekeller wrote: post #47

Earlier quoted context omitted.

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.

Dead reckoning based on heading and time alone, but if you have a good INS it's not affected by wind only by accuracy of the gyroscopes/sensors.

Current systems drift by about 0.5 miles per hour. And that's normal commercial grade systems, I'm sure the military has an option for better systems if they need them.

Re: BPS is a GPS alternative that nobody's heard of

#59

Post by [deleted] »

cameldrv wrote: post #52
zinekeller wrote: post #47

Earlier quoted context omitted.

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.

[deleted]

Re: BPS is a GPS alternative that nobody's heard of

#60

Post by TeMPOraL »

Alive-in-2025 wrote: post #49
1970-01-01 wrote: post #34

Earlier quoted context omitted.

Same feeling here. ATSC 3.0 with DRM and persistent Internet requirements tells me this is going to be the downfall of OTA television. I can see ATSC 4.0 being a discounted ISP subscription paired with some OTA location checks via BPS.

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 confusion in the offer structure, you can sell people on anything. Half the time you can just offer sportsball access and people will switch.

It's how previous versions of broadcaster overreach happened, and why Smart TVs succeed despite their shortcomings.

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