A lot of us will use satellite communications without thinking much about the satellite itself. It’s tempting to imagine that up there in orbit is a communications hub and distribution node of breathtaking complexity and ingenuity, but it might come as a surprise to some people that most communications satellites are simple transponders. They listen on one frequency band, and shift what they hear to another upon which they rebroadcast it.
This simplicity is not without weakness, for example the phenomenon of satellite hijacking has a history stretching back decades. In the 1980s for example there were stories abroad of …read more http://pje.fyi/Ps1jzt