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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 invo

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 timing, not navigation yet). The ultimate plan—which is probably dependent on how well ATSC 3.0 rolls out (which has plenty of hurdles[1])—is to encourage broadcasters to add on the necessary timing equipment to their transmitter sites, to build a mesh network for timing. That would allow the system to be 100% independent of GPS (time transfer could be done via dark fiber and/or ground-satellite-ground directly to some 'master' sites). The advantages for BPS are coverage (somewhat) inside buildings, the ability to have line of sight nearly everywhere in populated areas, and resilience to jamming you can't get with GPS (a 100 kW transmitter signal 10 miles away is a lot harder to defeat than a weak GPS signal hundreds of miles away in the sky). The demo on the show floor was also using eLoran to distribute time from a site in Nevada to the transmitter facility on Black Mountain outside Vegas, showing a way to be fully GPS-independent (though the current eLoran timing was sourced from GPS). [1] ATSC 3.0, as it is being rolled out in the US, doesn't even add on 4K (just 1080p HDR), and tacks on 'features' like 'show replay' (where you tap a button and an app can stream a show you're watching on OTA TV through the Internet... amazing! /s), DRM (at stations' discretion, ugh), and 'personalized ad injection' (no doubt requiring you to connect your TV to the Internet so advertisers can get your precise location too...). Because ATSC 3.0 requires new hardware, consumers have to be motivated to buy new TVs or converter boxes—I don't see anything that motivates me to do so. I feel like it may be a lot like the (forever ongoing) HD Radio rollout.

toast0 2y ago
I bought an atsc 3 tuner, and the experience turned me off of OTA tv. Since then, things managed to get worse as when I was poking around, DRM wasn't in use, but now it is. I was hoping to get better fidelity between the roughly 2x bitrate per channel, and the video codec update. And probably overly optimistically was hoping the 1080p feed source was progressive so there wouldn't be a deinterlacing step. Otoh, local broadcasters use an audio codec I can't easily use, integration with mythtv is poor, and there's no sign anything is going to get better soon. Maybe if I had a tv with an atsc 3 tuner, live tv would be an option, but I'm not buying a tv for that. ATSC 1.0 took a while before gathering momentum, so maybe that's going to be the same here, and in another few years, it might make sense to consider a transition. OTOH, maybe the writing is on the wall and OTA broadcasting will die on this hill. I was an OTA enthusiast, but between ATSC 3 being terrible, and the reallocation of spectrum that means cellular base stations sometimes overwhelm my pre-amp, it's not much fun anymore. (I have a filter post-pre-amp but it'd be better if I got on the roof to put it pre-pre-amp, but roofs are scary) Maybe I'm just getting curmudgeonly though.
The_Double 2y ago
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.
- fnordpiglet 2y ago
  The the transmitters are of fixed terrestrial locations.
  - namibj 2y ago
    The satellites are on known positions too, once you know the time.
  - michaelt 2y ago
    So you set your clock up by telling it its own location, so it can offset for the signal's flight time?
    - rocqua 2y ago
      No, you tell it the location of multiple towers it receives signals from, then it can compute the unique solution x, y, z, t
      - brookst 2y ago
        But the comment several levels up said they were demoing time with a single tower.
        mcculley 2y ago
        You can get time with a single tower, but not location.
        brookst 2y ago
throw0101d 2y ago
> The demo on the show floor was also using eLoran to distribute time from a site in Nevada to the transmitter facility on Black Mountain outside Vegas, showing a way to be fully GPS-independent (though the current eLoran timing was sourced from GPS). There's been a consistent call by many people that there needs to be a diversity of options for navigation and timing: * https://rntfnd.org/2025/02/04/pnt-gps-critical-issue-for-new-administration-and-congress/ https://rntfnd.org/2025/02/04/pnt-gps-critical-issue-for-new... China has GNSS (BeiDou, plus plans for LEO), plus terrestrial navigation (eLoran), plus a fibre-based network for accurate timing: * https://rntfnd.org/2024/10/03/china-completes-national-eloran-network-the-paper/ https://rntfnd.org/2024/10/03/china-completes-national-elora... * https://rntfnd.org/2024/03/01/patton-read-their-book-chinas-pnt-projects-and-ambitions/ https://rntfnd.org/2024/03/01/patton-read-their-book-chinas-... * https://rntfnd.org/2024/11/29/china-announces-plan-to-further-shade-gps-dominate-global-pnt/ https://rntfnd.org/2024/11/29/china-announces-plan-to-furthe... Russia has a Loran-equivalent: * https://en.wikipedia.org/wiki/CHAYKA https://en.wikipedia.org/wiki/CHAYKA
- mschuster91 2y ago
  Well... and there's the electricity grid which can be used for timing needs accurate enough to a single second, and in Europe there's DCF77 [1] which can not just be used as a 2*10^-12 seconds-accurate timing standard but also a frequency standard. [1] https://de.wikipedia.org/wiki/DCF77 https://de.wikipedia.org/wiki/DCF77
ksec 2y ago
Why is US ATSC 3.0 so bad? It is nearly a decade since it was South Korea have it deployed and operational. The standard itself is no longer "next gen". Brazil's TV 3.0, also uses ATSC 3.0 is so much better in every aspect. Even if someone mandate it as requirement for TV sold next year all the tech inside are at least 10 years old ( HEVC ? ) . Not to mention the roll out time. Do Americans only watch Cables and Netflix? And not Free to Air TV? Which is what I belief what most of the worst still do to a larger extend other than Internet streaming. They might as well look into the standards before putting a mandate into it.
- extra88 2y ago
  Only "18% of U.S. TV households had at least one TV set enabled to receive free, broadcast programming." https://www.nielsen.com/insights/2024/beyond-big-data-the-audience-watching-over-the-air/ https://www.nielsen.com/insights/2024/beyond-big-data-the-au...
  - ksec 2y ago
    Wow. Thanks. So when an Americans say they are watching TV, I assume that mostly meant watching Netflix or Cables?
    - p_ing 2y ago
      Cable is losing subscribers, too. https://evoca.tv/cord-cutting-statistics/ https://evoca.tv/cord-cutting-statistics/
      - ksec 2y ago
        Thank You. I guess I will submit this as an operate entry. Mind blowing figures.
    - extra88 2y ago
      Yes. Satellite dishes also provide service like cable does, a number of "basic" channels included plus options for "premium" channels that cost extra. The basic channels include the broadcast networks for one's geographic area. They're not that popular but there are similar bundles available over the Internet, YouTube TV is one. All the national broadcast networks have Internet options, Hulu has shows from multiple networks, Paramount+ has CBS. Both also have shows made for cable & satellite channels and Internet-only programming. There's a lot more than Netflix too, Amazon Prime, AppleTV+, Disney+, Max, and many others. Live sports kept people signed up to cable & satellite for a long time, I think now there are Internet options (and probably exclusives, I don't watch sports). This is from 2022: https://www.nielsen.com/insights/2022/broadband-only-tv-homes-amplify-sports-viewership/ https://www.nielsen.com/insights/2022/broadband-only-tv-home...
lsaferite 2y ago
Did you actually mention what BPS actually stands for in the article? I read the whole thing and don't recall reading that. Yes, I'm capable of searching and finding the information myself, but in an article about something something esoteric like this, explaining the acronym would be useful. Edit: Broadcast Positioning System for anyone that didn't figure it out.

toast0 2y ago

I bought an atsc 3 tuner, and the experience turned me off of OTA tv. Since then, things managed to get worse as when I was poking around, DRM wasn't in use, but now it is. I was hoping to get better fidelity between the roughly 2x bitrate per channel, and the video codec update. And probably overly optimistically was hoping the 1080p feed source was progressive so there wouldn't be a deinterlacing step. Otoh, local broadcasters use an audio codec I can't easily use, integration with mythtv is poor, and there's no sign anything is going to get better soon. Maybe if I had a tv with an atsc 3 tuner, live tv would be an option, but I'm not buying a tv for that. ATSC 1.0 took a while before gathering momentum, so maybe that's going to be the same here, and in another few years, it might make sense to consider a transition. OTOH, maybe the writing is on the wall and OTA broadcasting will die on this hill. I was an OTA enthusiast, but between ATSC 3 being terrible, and the reallocation of spectrum that means cellular base stations sometimes overwhelm my pre-amp, it's not much fun anymore. (I have a filter post-pre-amp but it'd be better if I got on the roof to put it pre-pre-amp, but roofs are scary) Maybe I'm just getting curmudgeonly though.

The_Double 2y ago

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.

fnordpiglet 2y ago
The the transmitters are of fixed terrestrial locations.
- namibj 2y ago
  The satellites are on known positions too, once you know the time.
- michaelt 2y ago
  So you set your clock up by telling it its own location, so it can offset for the signal's flight time?
  - rocqua 2y ago
    No, you tell it the location of multiple towers it receives signals from, then it can compute the unique solution x, y, z, t
    - brookst 2y ago
      But the comment several levels up said they were demoing time with a single tower.
      - mcculley 2y ago
        You can get time with a single tower, but not location.
        brookst 2y ago

throw0101d 2y ago

> The demo on the show floor was also using eLoran to distribute time from a site in Nevada to the transmitter facility on Black Mountain outside Vegas, showing a way to be fully GPS-independent (though the current eLoran timing was sourced from GPS). There's been a consistent call by many people that there needs to be a diversity of options for navigation and timing: * https://rntfnd.org/2025/02/04/pnt-gps-critical-issue-for-new-administration-and-congress/ https://rntfnd.org/2025/02/04/pnt-gps-critical-issue-for-new... China has GNSS (BeiDou, plus plans for LEO), plus terrestrial navigation (eLoran), plus a fibre-based network for accurate timing: * https://rntfnd.org/2024/10/03/china-completes-national-eloran-network-the-paper/ https://rntfnd.org/2024/10/03/china-completes-national-elora... * https://rntfnd.org/2024/03/01/patton-read-their-book-chinas-pnt-projects-and-ambitions/ https://rntfnd.org/2024/03/01/patton-read-their-book-chinas-... * https://rntfnd.org/2024/11/29/china-announces-plan-to-further-shade-gps-dominate-global-pnt/ https://rntfnd.org/2024/11/29/china-announces-plan-to-furthe... Russia has a Loran-equivalent: * https://en.wikipedia.org/wiki/CHAYKA https://en.wikipedia.org/wiki/CHAYKA

mschuster91 2y ago
Well... and there's the electricity grid which can be used for timing needs accurate enough to a single second, and in Europe there's DCF77 [1] which can not just be used as a 2*10^-12 seconds-accurate timing standard but also a frequency standard. [1] https://de.wikipedia.org/wiki/DCF77 https://de.wikipedia.org/wiki/DCF77

ksec 2y ago

Why is US ATSC 3.0 so bad? It is nearly a decade since it was South Korea have it deployed and operational. The standard itself is no longer "next gen". Brazil's TV 3.0, also uses ATSC 3.0 is so much better in every aspect. Even if someone mandate it as requirement for TV sold next year all the tech inside are at least 10 years old ( HEVC ? ) . Not to mention the roll out time. Do Americans only watch Cables and Netflix? And not Free to Air TV? Which is what I belief what most of the worst still do to a larger extend other than Internet streaming. They might as well look into the standards before putting a mandate into it.

extra88 2y ago
Only "18% of U.S. TV households had at least one TV set enabled to receive free, broadcast programming." https://www.nielsen.com/insights/2024/beyond-big-data-the-audience-watching-over-the-air/ https://www.nielsen.com/insights/2024/beyond-big-data-the-au...
- ksec 2y ago
  Wow. Thanks. So when an Americans say they are watching TV, I assume that mostly meant watching Netflix or Cables?
  - p_ing 2y ago
    Cable is losing subscribers, too. https://evoca.tv/cord-cutting-statistics/ https://evoca.tv/cord-cutting-statistics/
    - ksec 2y ago
      Thank You. I guess I will submit this as an operate entry. Mind blowing figures.
  - extra88 2y ago
    Yes. Satellite dishes also provide service like cable does, a number of "basic" channels included plus options for "premium" channels that cost extra. The basic channels include the broadcast networks for one's geographic area. They're not that popular but there are similar bundles available over the Internet, YouTube TV is one. All the national broadcast networks have Internet options, Hulu has shows from multiple networks, Paramount+ has CBS. Both also have shows made for cable & satellite channels and Internet-only programming. There's a lot more than Netflix too, Amazon Prime, AppleTV+, Disney+, Max, and many others. Live sports kept people signed up to cable & satellite for a long time, I think now there are Internet options (and probably exclusives, I don't watch sports). This is from 2022: https://www.nielsen.com/insights/2022/broadband-only-tv-homes-amplify-sports-viewership/ https://www.nielsen.com/insights/2022/broadband-only-tv-home...

lsaferite 2y ago

Did you actually mention what BPS actually stands for in the article? I read the whole thing and don't recall reading that. Yes, I'm capable of searching and finding the information myself, but in an article about something something esoteric like this, explaining the acronym would be useful. Edit: Broadcast Positioning System for anyone that didn't figure it out.