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Satellite TV and two way Internet by Satellite both come from Geostationary satellites so that you can use a fixed dish. GPS, ISS (International Space Station), Iridium (Sat phones) use LEO (Low Earth Orbit), this means they may pass overhead in as little as 20 minutes and can only be used with an Active Tracking Dish/Aerial or Omnidirectional Aerial. Satellite, like other Wireless systems, use different bands. L-Band is about 1.4GHz (1400MHz) and used by portable systems such as World Space. C-Band is about 4GHz and traditionally used to feed Cable Systems. The beam is usually large (which means lower power density at receive site) and a Dish needs to be twice the diameter at 1/2 the frequency so has to be typically 3.7m diameter. Most TV DTH (Direct To Home) and low cost "Satellite Broadband" (Two Way Internet by Satellite) uses Ku band (from under K band) about 10.7Ghz to 12.5GHz. Newer systems have up to four times bandwidth and 70 beams instead of one or two beams, giving over all
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