The satellite dish above can be considered reflective properties of parabolas. The signals that are received are directly sent to the focus, which are then correctly reflected to a receiver (signals are sent out parallel to the axis). These signals are then interpreted and are transmitted as channels on our TV. The same principle applies to radio frequencies too. Parabolic mirrors and heaters also work on the same principle.
Nice find with the article. It points to an array of examples. To get the equation of the parabola in the satellite dish, just rotate it, so that the focus is pointing straight up. By the way, these kinds of dishes can be as large as 1000 ft across. My parents have an old one in their backyard that is about 8 ft across. Here is a link to photo and article of the largest one on record, in Arecibo, Puerto Rico:
http://users.telenet.be/cr43155/articlesa1.html