The wonders of satellite dishes

Super Bowl XXX is one for the books, and it'll be a few months yet before the pitch that opens baseball season is thrown. There is still golf and hoops, but what's a couch potato to do when there are only a handful of sports channels to surf? It's time to dish up some satellite television. Elmer's off to Tube Town for an electronics upgrade faster than you can say "surround sound" when he muses, "I wonder how those tiny satellite dishes pick up 150 channels?" While he maxes out his credit card, let's get an SwRI Whizard to explain the wonders of satellite-to-home television.

"You can't blame Elmer for wanting the latest in home entertainment - it's pretty snazzy stuff. But he's not the only guy on the block who's interested. In fact, it's estimated that over the next five years, direct broadcast satellite equipment will be installed in 10 to 15 million homes in the U.S. alone.

"Satellite television is not new - those large dishes that typically occupy half the backyard have been around for several years now. However, those systems require the dish antenna to be repositioned toward different satellites. Additionally, the signals being transmitted don't use the new digital processing techniques nor do they offer the number of channels available with the new systems, so there's no way Elmer's going to get the variety he desires.

"So how does direct broadcast satellite television work? A satellite television service located on the ground collects broadcast channel information and transmits a signal to one of several satellites in geosynchronous orbit high above the Earth. A satellite in geosynchronous orbit moves at a rate identical to the Earth's rotation, so it is always at the same location. Back on Earth, Elmer's home-based, mini satellite dish intercepts the geosynchronous satellite's signal that includes hundreds of television channels. Using the new receiver equipment, which is connected to his standard television, Elmer then selects the channel of interest, and he's in business.

"As Elmer heads in to make his purchase, he should be aware that he has several options from which to choose. He must decide on a type of service, the style of hardware, and a host of equipment features. He should also be aware that most of the new systems are incompatible with each other and cannot receive programming from more than one service provider. So once Elmer invests in a certain brand of equipment, it will require a substantial investment on his part to switch services, should he become bored with his present selection."

Thanks to this month's Whizard, Pike Castles, director of the Surveillance Engineering Department in the SwRI Electromagnetics Division. Castles specializes in developing satellite-based tracking and combat identification systems for worldwide use.

The Lighter Side SwRI Home

March 25, 2013