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That's essentially what he's doing. The patch antenna he's using have a null at the horizon, where ground-based jammers would be.
OK, thanks. That info wasn't in TFA, nor in the article it linked to.
https://olegkutkov.me/2023/11/07/connecting-external-gps-ant...
Surely, a satellite in orbit could easily jam Starlink boxes on the ground.
>> IMMUNE TO JAMMERS No. That is not a thing. At most, one can make equipment less susceptible to jamming. Jamming is not like hacking, it isn't a matter of whether an attack works or does not. It cannot be fixed via a patch. Pump out enough energy close enough to the target and even a hyper-directional antenna can be jammed. Have a look at military GPS jammers. They aren't the little dongles that you can buy online…
Atomic clock and hard coded GPS Location for the win?!
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Pre-agreed time? Don't the satellites pulse a "The current time is x" signal? With signals from 4 satellites one can triangulate oneself in 3D space, with 5 signals, in 4D! (3D + time). I once did the math and astounded myself that it worked.
If there is no agreed time then you don't know when the signals were sent and cannot make any sense out of the signal. They all have to send either in unison or according to a predetermined schedule. The synced clocks set that schedule.
It will get another signal from another satellite, which could have the timestamp before X, because it left earlier and took longer to get to your receiver.
As I said, if you do the math, with 5 signals you can then determine your location in 3D space, and time!
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> One of the downsides is that it jams the AESA radars of friendlies in the area, including the plane using the jammer itself. So you just lob in a heat seeker at the middle of the noise, and hope. Then again, if you have an airborne source of jamming, you know you have bigger problems following. How much effort do you spend trying to knock out the jamming vs preparing for what is inevitably following? Flying in jamm…
> So you just lob in a heat seeker at the middle of the noise, and hope. There's already another category of missile for that: https://en.wikipedia.org/wiki/Anti-radiation_missile
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That is not feasible at a cost any current nation state could afford. Due to the inverse square law, the power output requirements to achieve any noticeable jamming from geostationary orbit would be enormous . There have been limited tests of fission reactors in space but they are too complex to operate reliably unattended for long. So, satellites are going to limited to solar or RTG power.
Only if using old school ‘blanket the area’ monopole antennas or if the goal was to cover the entire potential area all at once -but that seems unlikely to be desirable most of the time. Phased arrays and beam steering would allow them to pick and choose the area at will with high resolution - or even specific targets like several hundred airliners at once. Notably, the same things that starlink needs for being able…
Look at this animation[1] for a moment (click the >> or >>> button to speed up) and think about what it would actually take to get "in front" of enough satellites to block out a given geographic region; even just a single city. There are hundreds of satellites in each orbital plane, rapidly cycling through and taking each others' place.
You obviously cannot have counter-satellites in a geosynchronous "position", and you also can't have satellites simply move between greatly different orbits (or phases of existing orbits) willy nilly; The delta-V requirements are just too great. This just isn't a feasible strategy.
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Given the wavelengths and distances involved there are severe physics limits to how much beams can be steered and focused. These aren't lasers. What you are proposing isn't practical at a cost any nation state can currently afford.
You seem really invested in ‘no one could afford it’, even at lower orbits. Which seems pretty hilarious considering how much is getting spent on all this tech, and how much of an arms race it clearly is. Especially considering how TS programs in general are usually a decade or two ahead tech wise anyway. [ https://www.defenseone.com/threats/2022/04/dia-warns-chinas-... ] If you think there aren’t surprises hiding in…
Are you skimming over this part? Of course enemy nation states have invested in jamming capability... just not on this front
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You seem really invested in ‘no one could afford it’, even at lower orbits. Which seems pretty hilarious considering how much is getting spent on all this tech, and how much of an arms race it clearly is. Especially considering how TS programs in general are usually a decade or two ahead tech wise anyway. [ https://www.defenseone.com/threats/2022/04/dia-warns-chinas-... ] If you think there aren’t surprises hiding in…
> there are severe physics limits to how much beams can be steered and focused. Are you skimming over this part? Of course enemy nation states have invested in jamming capability... just not on this front
While not responding to my other comments?