Re: satellite phone
i think the satellite communication, there is international gate way, this international gate way is dish in the earth surface work as a transmitter and reciver and each gate way can cover spicific area, so if you wanna make a call, you willbe connected to the GSM network but on spicial channels, and after that your date will move to the gate way and transfer to the satellite, and in the gate way the modulation and demodulation .
about the sim cards it cant be used in the normal phones
regards