What is a spherical dish antenna required for satellite tv reception?

The parabolic antenna is really not an antenna at all - but a collector/reflector, which catches and concentrates RF (radio frequency) into a tiny antenna mounted above the dish, pointed into the dish. Since satellites transmit at very high frequencies (microwave), the actual antenna can be shorter than one inch. To strenghen the signal and make aiming the antenna at the satellite easier, the parabolic reflector picks up a wider area of RF.