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They resort to jamming at times: https://ir.usembassy.gov/the-iranian-regime-continues-jamming-foreign-mediums/ https://ir.usembassy.gov/the-iranian-regime-con

They resort to jamming at times: https://ir.usembassy.gov/the-iranian-regime-continues-jamming-foreign-mediums/ https://ir.usembassy.gov/the-iranian-regime-continues-jammin... https://www.wsj.com/articles/SB10001424052970203501304577088380199787036 https://www.wsj.com/articles/SB10001424052970203501304577088...

DoctorOetker 6y ago
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?
- walrus01 6y ago
  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://aviatnetworks.com/tag/class-4-antennas/ https://www.commscope.com/blog/2015/the-benefits-of-class-4-microwave-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.
  - syedkarim 6y ago
    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.
    - walrus01 6y ago
      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.
tyingq 6y ago
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.

DoctorOetker 6y ago

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?

walrus01 6y ago
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://aviatnetworks.com/tag/class-4-antennas/ https://www.commscope.com/blog/2015/the-benefits-of-class-4-microwave-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.
- syedkarim 6y ago
  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.
  - walrus01 6y ago
    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.

tyingq 6y ago

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.