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Comment by angry_octet | Hacker News Reader

This article is really glossing over the fact that non-military jamming now occurs all the time, courtesy of truckers and criminals. Actual GPS jamming is only done rarely on special military ranges with significant separation from civilian traffic, or very rare wide-area trials (days when I would not have flown anywhere near the area in the NOTAM).

One thing is true: GA and Amati pilots rely too heavily in GPS. If they can't fly with DR+VOR in VFR then maybe they shouldn't fly through an area with GPS interference...

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Try explaining that to the FAA. They've been shutting down more VORs and airways every year.

The FAA is guilty of cost focused magical thinking. They had some idea that anti-jam techniques would migrate to civilian platforms, but that is delusional, especially as the number of GPS enabled in flight devices has exploded. Maybe for special certified devices for ADS-B. But it is extremely sensitive tech, and anything smarter than a noise jammer can be difficult to deal with.

I think they plan on having jamming surveillance nodes set up near airports. But of course, detecting isn't fixing. How long did that (imaginary?) drone take out Heathrow airport for?

It's not that awful of a problem. Simply making the antenna directional enough is a solution, such as using a phased array coupled with an IMU to tell if the signal is coming from a known satellite location.

It depends on how severe and consistent the jamming is. If the receiver has a good lock (and a good clock) and a basic IMU then jamming on the last few minutes of approach might not cause too much drift -- but it could certainly spook a pilot into diverting.

As to mitigation, it is all expensive (in terms of antenna construction and processing) and GA is price sensitive. Airports with urban buildup get multi-path interference in the GPS signal and jamming signals, and it becomes complicated to computationally null the jamming signals. Chirp jammers are now as cheap as basic noise jammers.

Anyway, it's not so easy, look at any current research paper on anti-jam. Imagine if 500 MAGA/Antifa types plugged in PPDs over a city wide area and kept them mobile? It would be chaos.

Why are truckers causing GPS jamming?

Logging software uses GPS. If they jam it they can go off route or otherwise not have big brother watching them. I imagine it's becoming somewhat less prevalent though, as it's widely known they do it, enforcement has ratcheted up, and it's obvious when trucks just drop off the face of the earth all the time. It's not like 15 years ago when cell networks were much more sparse.

At a guess, I'd say the way they drive is tightly controlled by hiring companies via GPS logs (eg too many / not enough breaks, no driving over / under speed).

Driver fatigue rules often require mandatory rest stops. I. The past this was achieved by writing the rest break in a log book and taking some more uppers. Pesky GPS trackers showed that the break wasn't being done.

It's also traditional to take a load to a yard and rip out the good stuff and reseal it. Chain of custody in shipping is pretty weak. So much more painful if being GPS tracked.

Delivery drivers get rewarded for making all their runs on time, and getting streaks of on time runs, but this is often impossible. So they hand off some deliveries to third parties. But that is very painful if your vehicle is being tracked. GPS is often wonky in urban areas so hard to know for sure if a driver is fuzzing some runs.

As fleet management software gets smarter it will become pointless. But there is a disincentive to fixing log forgery -- cheaper freight. Deaths are externalized costs.

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