We have Dish Network, and the dish itself is on the corner of the roof. Fortunately it's only one story up, and I can reach it from the deck.
We purchased a cover for the dish and receiver arm (properly called the feedhorn and Low Noise Block Converter, or LBNF). It does keep most of the snow off of the dish itself, but then snow sometimes builds up on the cover, and I have to sweep it off.
I bought a three section extendable paint pole, and a large ball-shaped cobweb duster (sometimes sold as a Webster) and screwed the duster onto the pole. I usually have to sweep the snow from the cover once or twice per storm, if the snow is wet and heavy.
Hope this helps!
Peace