A Transmission System at a Radio Station Uses.
or transmission facility is an installation used for transmitting radio frequency signals for wireless communication, broadcasting, microwave link, mobile phone or other purposes.
Choice of location
The location may be called to fit the coverage area
and for VHF-UHF-applications line of sight considerations. For lower frequencies a location with good ground conductivity is required. In case of microwave link bondage, stations should be in observable ranges of each other. (come across Globe bulge) Computer programmes for the terrain profile and abacs are used in addition to on site observations. Abstention of industrial noise is also taken into consideration. Some other parameter may be the government regulations apropos public wellness requiring a minimum distance to human habitation. The distance depends on the power and the frequency of the transmitting indicate. Low power stations may be in cities; higher ability stations are ever in rural areas. Near of the stations (especially high frequency stations) are located at high altitudes. And then, both the minimum distance regulations and the line of sight criteria are met.
Buildings and antenna masts
Stations may be housed in several buildings or a single building. In some cases the station is nothing but a small-scale container.
They all take masts or towers to install antenna systems. In well-nigh cases, the mast is a passive structure to support the antennas. Only in low frequency stations (such equally AM radio), the mast itself may be the active antenna element. In such cases, the mast is isolated from the ground.(Run across
Monopole antenna). If the mast itself is an active antenna chemical element, the ground tin exist covered by a mesh of wires or metal elements to create a reflecting ground. Most of the stations too accept facility to receive microwave signals from a microwave link or a telecommunication satellite, (TVRO or RRO).
Most stations use mains electricity, only they also have standby generators or solar free energy panels in case of failure.
If the voltage of the mains fluctuates, a high power voltage regulator may exist used.
Like all industrial sites, the buildings, the antenna masts, the generators, and the transmitting equipment of the stations should exist grounded for personal safe against electric shocks. On the masts and roofs, lightning rods should be used. For transmitter stations working on frequencies beneath 30 MHz a good grounding is required for good function and sometimes excessive grounding systems are used. In most cases, it is desirable to connect the rods to each other to form a simple Faraday muzzle. But in high altitude stations, the ground is commonly rocky and finding an appropriate signal for the grounding jitney may exist impossible. In such cases, very long grounding connectors may be used to discover a good ground at lower altitudes.
Transmitters may be operated by government (civil or military machine) or individual manufacture. Many stations are unattended and controlled past remote control equipment. Where operating personnel are required, personnel work on shifts and transportation may too be a parameter of station blueprint. In such cases, accommodation, catering and health problems besides play a role in station direction. Especially in loftier distance stations, snowmobiles must exist used during winter.
Virtually AM radio transmitters are loftier-power equipment. Because of the relatively low frequency they use, they don’t demand to exist located in high places. They may broadcast in LW (long wave), MW (medium wave) or SW (short wave). Since SW stations are assigned for very long altitude communication (via reflections from atmospheric layers) they are usually employed for multi-language international services and there may be many SW transmitters in the same station.
Boob tube and FM (frequency modulated ) radio transmitter stations too as transposer stations are about ever built on top of hills. A single station may take many transmitters both for TV and FM. In rare cases, each transmitter has an antenna system. Only in stations where many transmitters are used, this is not e’er possible, so the outputs of transmitters transmitting in the aforementioned frequency band are combined by a diplexer and practical to a unmarried antenna system. (i.e. VHF ane, VHF 2, VHF 3, UHF). If two or more antenna systems have to be used, college frequency antennas are mounted college on the antenna mast. (The sequence of antenna systems on a typical Idiot box-FM station may exist from lesser to superlative; VHF-2, VHF-3 and UHF.) Microwave stations are also high distance stations. Although high altitude is desirable likewise in GSM, the operators may employ low power intracity stations for areas of loftier population density.
References and notes
European Broadcasting Union:Technical Monogram No.3104-1965 Site selection (Edited by RK.H.Kaltbeitzer),Chapter I, Brussels
European Broadcasting Wedlock:Technical Monogram No.3108-1967 High Altitude VHF and UHF Broadcast Stations (Edited by R.Busi),Chapter III, Brussels
A Transmission System at a Radio Station Uses