How the Dish Network and DirecTV Satellite systems work

Satellite is similar to over-the-air broadcasts that have been in use since the beginning of broadcast television, in that they are both line of sight technologies.  Over-the-air broadcast uses a big land based antenna to broadcast its signal to households.  At the household people use smaller antenna to receive the signal.  Radio signals sent out by the TV station’s antenna get weaker the further away you are from it; trees and small buildings don’t really get in the way of the signal, but big objects like a mountain will block or weaken the signal so much that it is unusable.

Dish Network and DirecTV satellite systems are basically an improved version of over-the-air broadcast television with a taller antenna, as satellites orbit the earth about 22,000 miles (35,000 KM) above the surface.  The orbit pattern is call geosynchronous, which means the satellite moves at the same speed and direction as the earth’s spin.  Thus its position is always fixed relative to any location on earth just like an old land based antenna.  With the broadcast coming from that much higher downward, obstacles are all but eliminated, so the line of sight is always clean.  The antenna that is used by each household (the satellite dish) is also much more efficient.

The other improvement is that all the broadcasts come from one location (the satellite), so you can point the receiving antenna (the satellite dish) directly at the broadcast antenna (the DirecTV or Dish Network satellite).  Under the old over-the-air system, you couldn’t use a directional antenna, since each broadcast antenna could be in different directions relative to your house (omni-directional). Compared to an omni-directional antenna, a directional antenna has an extended range of signal reception.

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