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GPS has been getting better over time. The newest iteration of the system supports a directional spot beam for military users with +20dB gain for theater-level jamming resistance.
A +20dB gain means that the jammer is going to need roughly 100x its current power output to maintain the same effectiveness. An adversary ramping their transmitter by this much would turn into a blazing hot target in terms of electronic warfare. There are entire classes of weapons designed to lock directly onto signals like this. The AGM-88 is an example.
A part of why GPS is such a weak point is that existing receivers out there are pretty basic. Including receivers in things like JDAMs and other PGKs.
This is even worse in Ukraine, where a lot of "precision munitions" are cobbled together from civilian parts and duct tape, jammers are cheap and plentiful, and anti-radiation missiles are unicorns.
>> precision munitions" are cobbled together from civilian parts and duct tape
Like the M982 Excalibur by Raytheon which is pretty much useless now in Ukraine.
Thats a problem for the Ukrainians, not the Pentagon. As far as jdams (some of) the ones in ukr have "home-on-jam" capabilities so no harm needed.
The Frank LoBiondo Coast Guard Authorization Act of 2018 had with-in it the provision National Timing Resilience and Security Act of 2018:
* https://rntfnd.org/wp-content/uploads/National-Timing-Resili...
A roadmap was published in 2021:
* https://www.transportation.gov/pnt/national-timing-resilienc...
And also from 2021, NATIONAL R&D PLAN FOR POSITIONING, NAVIGATION, AND TIMING RESILIENCE:
* https://bidenwhitehouse.archives.gov/wp-content/uploads/2021...
The simplest solution is to simply to resurrect the Loran infrastructure that the US (and others) run until the 2000s. The Koreans have been running eLoran for a while, and the UK and France are teaming up as well:
* https://insidegnss.com/uk-and-france-renew-ties-resilient-pn...
* https://rntfnd.org/2025/11/12/s-korea-leads-meeting-with-u-k...
Chinas has had a completely built out network (including fibre networks for high-precision timing) for over a year:
* https://rntfnd.org/2024/10/03/china-completes-national-elora...
This is not rocket surgery: a working system that can giver you continent-wide coverage can be up and running a few years, with little technical risk (there's already kit available).
Throwing some money at the problem and instructing the DOT/DHS/whomever to issue an RFI/RFP would go a long way to moving the ball forward.
Something like LORAN would be useful for operations near friendly nations and/or relatively uncontested areas.
They don't particularly help with striking Chinese assets. Which is what the DoD funding is primarily about.
> They don't particularly help with striking Chinese assets. Which is what the DoD funding is primarily about.
Why not use China's own Loran (and BeiDou) system against them?
I was with a friend visiting O'hare approach control outside Chicago. As with our previous visit to the Regional air traffic control, I was there mostly to give my friend a ride. However, on this visit I asked a question when the opportunity arose
"What would you do if GPS went out, permanently?"
The whole room collectively didn't want to think about it. There doesn't appear to be a plan. We've collectively put all our eggs in one basket.
I think air traffic is probably the most resilient group - I’m surprised no one answered!
IFR was designed long before GPS and for the most part, GPS has been shoehorned into the “old” system. VORs around the country are still “primary” for navigations; airways are still primarily defined around VOR radials; and approach plates to large airports have plenty of non-GPS precision approaches. (Some smaller GA-only airfields that recently got IFR approaches might be WAAS/GPS only).
Losing GPS might increase workload for some sectors (en route sectors who won’t be able to clear aircraft direct to waypoints) but not likely TRACON who are vectoring aircraft on pre-defined approach plates.
If you pick a random commercial flight on your favourite flight tracker and check it’s route, 99% of the waypoints on it are defined as VOR intersections, not GPS coordinates. (The remaining 1% are likely en-route waypoints and not in the departure/approach area).
Also, the instrument proficiency requirements for pilots require multiple approach types to be logged every 6 months so they are definitely capable of non-GPS approaches.
I remember reading something about defunding some satellites, so I went looking. All I could find is articles about the US not providing backup satellites.
https://www.npr.org/2024/09/27/nx-s1-5127737/losing-gps-woul...
https://www.nbcnewyork.com/news/business/money-report/losing...
Its about countering adversarial GPS spoofing, not a lack of satellites.
Why was that not a consideration from the start? Surely it is expected that any system with military applications will face jamming and spoofing?
I wonder if this changes the old adage, now that the missile knows where it is at all times. [0]
How does GPS stand up to the more recent European and Chinese systems?
Same type of system, same advantages, same vulnerabilities. Slightly different coverage densities.
GPS isn't poorly designed - it's well designed within its design constraints, which those systems share.
Sometimes it's important to step back and reserve that these green field systems are merely trading blows with something originally designed in the 80s which carries all that baggage to 2026.
I was under the impression that thr US Military doesn't use GPS; that it was a civilian thing and that they had something more precise and secure.
The US Military does use GPS, but ordinary civilians don't have access to high accuracy data. Commercial vendors can license for higher accuracy, but its a hybrid civilian/military system with higher quality data for military use cases.
I think that was previously the case, but not anymore. I can get within a couple meters accuracy on my phone, which is plenty good enough for weapons guidance.
GPS was built by the US military. Its existence was first revealed in Desert Storm back in 1990 when the US military used it to drive tanks into the desert, then come out where and when they wanted. The Iraqis were quite surprised, since they knew that desert, and knew that they would get lost if they tried to do the same maneuver.
Parts of the GPS signal are encrypted to be only useful for the military. The result is that civilian systems an average 4.9 meters of accuracy, while the military is precise to something like a meter instead. But that extra accuracy doesn't help if the signal is jammed.
It was revealed earlier than 1990. In 1983 it was publicly announced that it would be made available for civilian use. Hard to do that without its existence being revealed.
They use a different coding scheme on the same physical signal. It is resistant to spoofing but far from immune to jamming.
It was developed by and for the military and is still managed by the military. Those are not normal qualities of civilian only systems.
Paywalled
From another thread:
no paywall: https://www.wsj.com/tech/the-pentagon-cant-trust-gps-anymore...
And we can't trust the Pentago anymore, so the circle is completed (see the recent "Ukraine deal" which is basically just a sell-out toward the USA allying with Russia).
But was that "deal" even produced in the Pentagon? We can't trust the current White House anymore, but this was known since late 2024.
One study said the English language in the plan was likely written by a Russian native.
Written by The Kremlin, Jared Kushner and a Florida property developer (in that order).
You only stopped trusting the government in 2024?
Can you explain why you think that deal is selling out? It seems reasonable from the point of view of the United States given they don’t want to pour more money into a conflict they don’t really care too much about. Surely there are some lessons learnt from the “war on terror”
Rewarding aggression from Russia won’t save money (or lives) in the long run.
Abandoning Ukraine will only save money if the US also abandons NATO. After this the Baltic states are next.
US is not pouring money into the conflict. They are barely helping. Besides some intel and letting EU countries buy US made weapons for Ukraine.
For not caring to much, they try to take a lot of influence in a conflict that's not theirs
With this "deal" written by russians USA shows the whole world that their security assurance worth nothing. Also shows that NATO is dead.
This deal is an invite for president Xi to take back Taiwan and whatever territory he wants.
It’s selling out the Ukranians, they didn’t get a say in the deal and Putin gets to keep his gains and at home the threat of him being overthrown is lessened. In return Ukraine gets to give up territory and reduce their readiness for the next round of war after giving Putin the chance to build up and regroup.
The US isn’t pouring money into Ukraine. Under the PURL agreement this year it has switched to selling weapons at a mark up that is being paid for by NATO allies. So this plan is not only screwing our own defense industry in the short term, it is doing so in the long term by showing any agreement with the US can’t be trusted and if you agree to buy weapons from the US you may find your supply cut off randomly as you need them.
It's betraying the Bucharest assurances they made to protect Ukraine in exchange for giving up nuclear arms. So fuck that.
The "deal" is a laundry list of Putin's wants. Russia gets everything it wants and Ukraine loses everything it needs.
- Ukraine gives up everything they've lost thus far.
- Ukraine must surrender additional territory.
- Ukraine has to cull its military strength.
- It sets up Ukraine to fail to be able to defend itself when the next war begins and does nothing to prevent Russia from restarting the war.
- Russia sanctions end, Russia is invited back to the international stage without reprocussuons or restitution
- It rather grossly calls on America to invest significant money and resources in Russia's tech industry as restitution.
I've heard analysts say that Trump wants this so he can say he ended both the Israel/Palestine conflict as well as the Russia/Ukraine conflict. It's a total abdication by the loser of their sovereignty all for a feather in Trump's crown.
Ukraine has been given an ultimatum to accept this deal by Thanksgiving (a US holiday) or lose all American support. Including advanced warning of Russian attacks from US intelligence. We wouldn't tell them the Russians are coming. A total and complete shut down of US support such that Ukraine is completely blinded.
But if we could actually ally with Russia against China that would be a massive strategic win. Russia is:
1. A massive nuclear power
2. On the border of China
3. Willing to take risks for geopolitical gain that the Europeans would never dream of
4. A natural enemy of China since China claims (unofficially) large areas of Siberia including Vladivostok (their only major port on the Pacific).
If Russia were an ally, that would put our alliance to the north, east, and south of China. More importantly it would put the threat of a land based attack on the table which is currently not the case.
Russia is also a failing state with a crumbling economy and a demographic disaster unfolding, that is having issues pushing further than 50kms from its borders in a land war with the poorest European nation. They would only be a liability in a conflict against China.
What is this, a game of risk? Ignoring the multitude of issues with a Russia+US alliance (I don't think current leadership would ever trust each other), China would absolutely not be okay with the US on its doorstep.
Russia and China aren't exactly good friends, but this is a "the enemy of my enemy is my friend" situation. The US is not popular with either of them.
Russia will never fight against China. Moreover, Russia can already be considered a Chinese province.
Fabulously complicated and only producible with exotic emitters, sensors, and high frequency ICs.
Probably as easily jammed or forced into calibration state with a directed low frequency em pulse generator.
High tech garbage. We will not fare any better than Ukraine relying on tech like this.
Fortunately someone recently posted a real technological wonder - the F-14 cpu, old timers were messing with multithreaded compute while I was muddling along learning pong line by line from a hobbyist magazine.
Probably right. But,
> We will not fare any better than Ukraine relying on tech like this.
Ukraine is faring amazing well, aren’t they?
Russia controls a fraction of the territory, has suffered a million casualties, and lost many many armored vehicles and combat aircraft.