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by amiruci2 2096 days ago
They resort to jamming at times: https://ir.usembassy.gov/the-iranian-regime-continues-jammin... https://www.wsj.com/articles/SB10001424052970203501304577088...
2 comments

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.
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.