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Comment by BelleOfTheBall | Hacker News Reader

What a fascinating way to fight a totalitarian crackdown. The article doesn't seem to talk about its feasibility against the government though. Is there no way they could stop it, bar actually damaging people's satellite dishes?

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They resort to jamming at times: https://ir.usembassy.gov/the-iranian-regime-continues-jammin... https://www.wsj.com/articles/SB10001424052970203501304577088...

can satellite dishes be redesigned such that they don't just have a directional peak in sensitivity, but also a controlled suitably low maximum sensitivity in other directions?

or is jamming typically done from drones / airplanes to jam a slanted conical region below them?

when they physically remove dishes, do they discover them typically visually (so they just need to be hidden in a RF transparent box say plastic) or do they already use direction finding on local oscillators?

You could design a receive only satellite dish with side shielding, even up to the point of making it technically equivalent to an ETSI class 4 antenna for licensed microwave systems, but it would look considerably different (like a drum with tall walls) and would cost a great deal more.

https://aviatnetworks.com/tag/class-4-antennas/

https://www.commscope.com/blog/2015/the-benefits-of-class-4-...

in general this is a very cost sensitive market if you go to a big city in pakistan, afghanistan or iran and look at the $100 satellite dishes with LNBs all over the roofs.

Those are $20 dishes and $3 LNBs. The dishes are just stamped sheet metal. The LNBs are highly integrated; mostly passives and a really cheap RF ICs.

That is a good point. I was being overly generous by far on the actual dish cost, and including the cost of cabling and a basic receiver set top box. But building a jam resistant rx only dish would still have significant economic challenges.

It would be hard to jam one channel on a satellite and not jam other channels. They multiplex about 10 tv channels per transponder on Ku band.

Assuming they encode it like a tv channel, it would be multiplexed on one transponder with roughly 9 other tv channels. So if the government tried to jam or block it, they would zap a bunch of legit television.

I don't know if the uplink is in Iran. If so, it would be trivial to shut it down.

Edit: Apparently the uplink is in the UAE.

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