Broadcasting chain
A broadcasting chain consists of various terrestrial broadcasting systems at different locations that broadcast a single radio program at the same time.
broadcast
The range of a single transmitter system is limited by various factors. The signals broadcast in the VHF radio and television range only have a quasi-optical range, i.e. they do not extend beyond the horizon and cannot easily reach deeper valleys as long as there is no (approximate) line of sight. In order to still be able to supply larger areas, such as individual federal states or entire states, with a radio program, additional transmitter systems are required at other locations. The entirety of all broadcasting systems that broadcast a program in this way is a broadcasting chain. One form of the transmitter chain is a single frequency network in which several transmitters broadcast the same program on one frequency without interfering with each other.
Transmitter chains are almost always necessary for nationwide coverage in the VHF and television areas. Historically, broadcasting chains also existed in medium wave broadcasting. Broadcast systems in the LW and SW range usually do not require a chain solution.
Broadcasting chains rarely consist of a number of equally strong broadcasters. As a rule, they are made up of basic network transmitters for large-scale coverage and filler transmitters to cover smaller areas not reached by large transmitters.
There are also transmitter chains with marine radio fires , the Decca navigation system , the LORAN navigation system, the disused OMEGA navigation system and the Russian Alpha navigation system , but here for the purpose of location determination.
literature
- Ingrid Mitterhummer: transmitter locations and frequencies . Ed .: Bayerischer Rundfunk (= tables, maps, numbers ). July 7, 2004, p. 14 ( fmtvdx.eu [PDF]).