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Comment by EthanHeilman | Hacker News Reader

Yes, but it is more difficult than jamming a typical radio antenna because the starlink uses a directed beam rather than a omnidirectional radio broadcast. This either requires enormous amounts of power, targeting the satellite itself with a directed radio beam, or getting between the satellite and the ground station by bouncing a signal off the ionosphere.

The above is for jamming directed beams in general. It is likely that starlink has a number of other jamming countermeasures.

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Bouncing signals off of the ionosphere is most definitely not an option here. The bandwidth of the signals that Starlink needs in order to provide service are far wider than the range of frequencies that bounce off any layer of the ionosphere. If you could get a 10GHz signal to bounce off of the F layer, you'd have a lot of very excited amateur radio operators who would start using that instead of the moon as their reflector.

Thanks for your comment, I know the ionosphere is used in Electronic Warfare but I didn't realize it was so limited in frequency.

Is there really is no way to reflect signals off the ionosphere out of phase so after reflecting they interfere into a higher frequency?

Just to add more details.

Beamforming is essentially yet another way to achieve gain, just like one does with a directional antenna. The Starlink terminal achieves a gain of roughly 33 dB, which means it talks (and also listens) in the peak direction at power levels that are around 2000x higher than what one would achieve with isotropic antennas. 2000x sounds like a lot, but it is actually not impossible to reach. Consumer electronics sends at most a few Watts of RF power, but serious jammers of the type used by militaries can run kilowatts. If you consider the peak power used for brief moments of time then you can get as high as megawatts - the famous AWACS aircraft briefly flash half a continent at somewhere around 1 MW, with average TX power of ~single digit kilowatt.

This assumes you're jamming very close to the dish. The trouble with jamming is you have to deal with the inverse square law so you really can't deny very much area. If they have a fleet of hundreds of high power modern directional jammers they could degrade this or other networks, but they're just not going to have that kind of sophistication.

Oh, I was thinking of jamming the receivers of the satellites. Should have written it explicitly, it is indeed not clear.

Either way, you'd need to jam several with quite a bit of power

Possible, yes, but the Iranian government almost certainly isn't capable of doing so, much less across the entire country.

Even Russians don't seem to be able to jam Starlink on the Ukrainian battlefields.

China, maybe.

Huge idiot here with an honest question: with starlink, could a rogue actor just point a bunch of high-powered lasers at the satellites and brick them?

Cheaper to launch a barrel of metal trash to the Starlink orbits. Or a few barrels. Iran has rockets for that.

There are 9400 active Starlink satellites & they can be launched 28 at a time on a partially reusable rocket. The orbit they operate on is largely self cleaning due to being quite low. The satellites operate in many planes and bands + form a mesh network with laster interconnects.

Sure, if you want to try that and bankrupt Iran even more via its militarry rocket program, you can do that and maybe destray a handfull satellites, provided you can actually hit them and the rocket/s does not fail. And you might even get a nice casus belli as a free extra.

you might be able to hit one but it'd be pretty impressive, like firing a bullet and hitting someone in another country impressive

I'm not a rocket scientist, but I guess even a single lunch in the retrograde direction should be enough. You lunch a box of ball bearings with a plastic explosive to spread them out, and then just wait. The cloud will pass over Iran every 12h or and will stay in orbit for quite a few weeks, since the orbit is even higher than ISS reboosting once a month, and balls are highly aerodynamic compared to the Starlink flat sails. The cloud won't be very big, but it will repeatedly swipe through quite a lot intersecting prograde orbits. I guess the chance would be quite high. Iran can also split payload into smaller boxes and "deploy" then in sequence while the second stage is firing, then detonate them, to spread out even more.

In short, likely no(unless the satellites are really sensitive). Otherwise lasers would have negated the fear of ICBMs long ago.

Because the atmosphere absorbs a lot of energy of the laser beam and focusing the laser beam to such a distant target is not easy. So you cannot just use some high powered lasers, as it would be just a bright spot at most. It would be different, if the laser would be space based, but that is out of reach of Iran's capabilities. They might have anti satellite rockets, but using them against US property in space would create other problems for them.

Multibeam too, right?

>targeting the satellite itself with a directed radio beam

And good luck targeting enough Starlink satellites...

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