SMATV is Single Master Antenna Television (or Satellite Master Antenna Television),[1] The purpose of SMATV is for supplying and controlling the number and type of channels to multiple televisions.[2] Not only TV channels but FM channels as well. It provides Reception of DBS TV/FM channels for hotels, motels, dormitories, schools, hospitals and commercial properties with multiple tenants. Using a master antenna system video signals, audio signals and decoder signals can also be distributed.
It consists of single outdoor unit or antenna feeding to number of indoor units.[3] The channels accessible are independent of other users. For maintaining a good signal-to-noise ratio at all the indoor units served, a larger antenna is required, typically 2 metres (6.6 ft) to 3 metres (9.8 ft) in diameter.
A SMATV headend is used to receive and rebroadcast satellite television channels throughout a property from a single satellite feed.[4]
The system consists of a master antenna and a matching transformer to match the balanced antenna with unbalanced cable and amplifiers.[5] Most antennas have an impedance of around 300 Ω. To convert it to 75 Ω, a matching transformer (orbalun) is used. For trunk line isolation, a resistive inductive device known as a splitter is used. The amplifier output is fed to the splitter through coaxial trunk lines.[6]
There are several methods of distribution that are often used in a SMATV headend. These include:
There are two main approaches for distribution of digital TV signals in SMATV installations:
In the United States, the satellite carriers providing the satellite TV signal for SMATV headend systems are:
