Satellite TV Reception

A television signal must be transmitted to a television receiver. The technicians at a television studio make use of a transmitter to produce a TV signal from separate audio and video signals. This TV signal is then carried by wire to be broadcast from an antenna.

This type of signal is an electromagnetic wave and travels at the speed of light. The strength of this wave however decreases with distance. In order to transmit signals much farther, fiberoptic cable, coaxial cable, microwaves and satellites are used. Our interest here is in satellite television.

Satellites carry TV signals between stations where cables or microwave towers cannot be constructed. This would include sending such signals across oceans. In space, satellites act like relay towers, for they receive coded TV signals from an Earth station, amplify them and then send them back to another Earth station.

Satellite TV systems use DBS or direct broadcast satellites to carry signals directly to the homes or offices of subscribers. This is where the famous dish comes into play. The dish shaped antenna used to measure as much as 10 feet across. Today the typical dish is no more than 18 inches across. Television signals reach a home TV set after they are sent to the dish, which is a form of receiving antenna, and are decoded by a receiver which converts the signals back into copies of the original light and sound waves.

In order to be effective, the dish must be aimed directly at the desired satellite. The satellite is in a geostationary orbit. Television reception by means of satellite also requires the use of this set top box for pay per view and premium programming.

DirecTV and digital satellite service may be covered in other articles but suffice to say the last few years have seen great leaps in technology and service. For now, let us continue with some more additions to our satellite TV glossary.

The antenna is an instrument which collects electromagnetic signals from a satellite. The collocation is the arrangement of several satellites near each other in orbit around Earth. This permits a single fixed receiving antenna to receive signals from all the satellites in question without tracking.

Terrestrial Interference is a satellite signal interruption caused by high power land based microwave links. It is also understood to be caused by signals originating from earth, usually microwave, which share a common downlink frequency. The transmitter is an electronic device made up of a modulator and oscillator that produce a radio or TV electromagnetic wave signal which is radiated into the atmosphere.

The satellite industry is complicated, but it is not really that much more complicated than cable is it now? When you think about it, everything has to be transmitted and received. One kind of signal sends out the transmission, the other kind of signal receives the transmission. In fact, the only reason satellite service seems more complicated is because it looks like there is another step involved. Instead of just sending the signal into our home from the cable studio, it must first go into space, then back to Earth, then back to space.