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Tower Array
A tower array is an arrangement of multiple radio towers which are mast radiators in a phased array. They were originally developed as ground-based tracking radars. Tower arrays can consist of free-standing or guyed towers or a mix of them. Tower arrays are used to constitute a directional antenna of a mediumwave or longwave radio station. The number of towers in a tower array can vary. In many arrays all towers have the same height, but there are also arrays of towers of different height. The arrangement can vary. For directional antennas with fixed radiation pattern, linear arrangements are preferred, while for switchable directional patterns (usually for daytime groundwave versus nighttime skywave), square arrangements are chosen. Examples Tower arrays with guyed masts * Longwave transmitter Europe 1 * Transmitter Weisskirchen * Beidweiler Longwave Transmitter * Transmitter Wachenbrunn * Transmitter Ismaning (VoA-Station) Tower arrays with free standing towers * Junglinster L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Masts And Towers
Radio masts and towers are typically tall structures designed to support antennas for telecommunications and broadcasting, including television. There are two main types: guyed and self-supporting structures. They are among the tallest human-made structures. Masts are often named after the broadcasting organizations that originally built them or currently use them. In the case of a mast radiator or radiating tower, the whole mast or tower is itself the transmitting antenna. Terminology The terms "mast" and "tower" are often used interchangeably. However, in structural engineering terms, a tower is a self-supporting or cantilevered structure, while a mast is held up by stays or guys. Broadcast engineers in the UK use the same terminology. A mast is a ground-based or rooftop structure that supports antennas at a height where they can satisfactorily send or receive radio waves. Typical masts are of steel lattice or tubular steel construction. Masts themselves play no part in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmitter Wachenbrunn
The Wachenbrunn transmitter was a large broadcasting facility for medium wave in Wachenbrunn near Themar, Thuringia, Germany, established in the 1950s. Until 1993 the main transmitter of this facility, the medium wave transmitter for 882 kHz was run with 250 kilowatts. In that year the transmission power of this transmitter, which was formerly used for transmitting the " Voice of DDR" and since the beginning of the 1990s for "MDR info" was reduced to 20 kilowatts. History Since 1988 the transmitter Wachenbrunn has also been the site of a medium wave transmitter of the Russian foreign radio service Voice of Russia (formerly Radio Moskau) on 1323 kHz. This transmitter is similar to the transmitter of "MDR info" run by Deutsche Telekom. In the afternoon and evening, a programme of the Voice of Russia was transmitted in German. With a power of 1000 kW, this transmitter was the third strongest in Germany. It used a directional aerial consisting of four 125.1 metre (407& ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communication Towers
Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inquiry studying them. There are many disagreements about its precise definition. John Peters argues that the difficulty of defining communication emerges from the fact that communication is both a universal phenomenon and a specific discipline of institutional academic study. One definitional strategy involves limiting what can be included in the category of communication (for example, requiring a "conscious intent" to persuade). By this logic, one possible definition of communication is the act of developing meaning among entities or groups through the use of sufficiently mutually understood signs, symbols, and semiotic conventions. An important distinction is between verbal communication, which happens through the use of a language, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications Infrastructure
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as coded drumbea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications Equipment
Telecommunications equipment (also telecoms equipment or communications equipment) are hardware which are used for the purposes of telecommunications. Since the 1990s the boundary between telecoms equipment and IT hardware has become blurred as a result of the growth of the internet and its increasing role in the transfer of telecoms data. Types Telecommunications equipment can be broadly broken down into the following categories: *Public switching equipment **Analogue switches **Digital switches ***Voice over IP switches ***Virtual reality (VR) *Transmission equipment **Transmission lines ***Optical fiber ***Local loops **Base transceiver stations **Free-space optical communication ***Laser communication in space **Multiplexers **Communications satellites *Customer premises equipment (CPE) ** Customer office terminal **Private switches **Local area networks (LANs) **Modems **Mobile phones ** Landline telephones **Answering machines **Teleprinters **Fax machines **Pagers ** Router ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcast Engineering
Broadcast engineering is the field of electrical engineering, and now to some extent computer engineering and information technology, which deals with radio and television broadcasting. Audio engineering and RF engineering are also essential parts of broadcast engineering, being their own subsets of electrical engineering. Broadcast engineering involves both the Television studio, studio and transmitter aspects (the entire airchain), as well as remote broadcasts. Every Broadcast network, station has a broadcast engineer, though one may now serve an entire station group in a city. In small media markets the engineer may work on a contract basis for one or more stations as needed. Duties Modern duties of a broadcast engineer include maintaining broadcast automation systems for the studio and automatic transmission systems for the transmitter physical plant, plant. There are also important duties regarding Radio masts and towers, radio towers, which must be Preventive maintenanc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directional Array
An antenna array (or array antenna) is a set of multiple connected antennas which work together as a single antenna, to transmit or receive radio waves. The individual antennas (called ''elements'') are usually connected to a single receiver or transmitter by feedlines that feed the power to the elements in a specific phase relationship. The radio waves radiated by each individual antenna combine and superpose, adding together ( interfering constructively) to enhance the power radiated in desired directions, and cancelling ( interfering destructively) to reduce the power radiated in other directions. Similarly, when used for receiving, the separate radio frequency currents from the individual antennas combine in the receiver with the correct phase relationship to enhance signals received from the desired directions and cancel signals from undesired directions. More sophisticated array antennas may have multiple transmitter or receiver modules, each connected to a separate ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medium Wave
Medium wave (MW) is the part of the medium frequency (MF) radio band used mainly for AM radio broadcasting. The spectrum provides about 120 channels with more limited sound quality than FM stations on the FM broadcast band. During the daytime, reception is usually limited to more local stations, though this is dependent on the signal conditions and quality of radio receiver used. Improved signal propagation at night allows the reception of much longer distance signals (within a range of about 2,000 km or 1,200 miles). This can cause increased interference because on most channels multiple transmitters operate simultaneously worldwide. In addition, amplitude modulation (AM) is often more prone to interference by various electronic devices, especially power supplies and computers. Strong transmitters cover larger areas than on the FM broadcast band but require more energy and longer antennas. Digital modes are possible but have not reached momentum yet. MW was the main radio ban ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longwave
In radio, longwave, long wave or long-wave, and commonly abbreviated LW, refers to parts of the radio spectrum with wavelengths longer than what was originally called the medium-wave broadcasting band. The term is historic, dating from the early 20th century, when the radio spectrum was considered to consist of longwave (LW), medium-wave (MW), and short-wave (SW) radio bands. Most modern radio systems and devices use wavelengths which would then have been considered 'ultra-short'. In contemporary usage, the term ''longwave'' is not defined precisely, and its intended meaning varies. It may be used for radio wavelengths longer than 1,000 m i.e. frequencies up to 300 kilohertz (kHz), including the International Telecommunication Union's (ITU's) low frequency (LF, 30–300 kHz) and very low frequency (VLF, 3–30 kHz) bands. Sometimes the upper limit is taken to be higher than 300 kHz, but not above the start of the medium wave broadcast band at 520&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directional Antenna
A directional antenna or beam antenna is an antenna which radiates or receives greater power in specific directions allowing increased performance and reduced interference from unwanted sources. Directional antennas provide increased performance over dipole antennas—or omnidirectional antennas in general—when greater concentration of radiation in a certain direction is desired. A high-gain antenna (HGA) is a directional antenna with a focused, narrow radiowave beam width, permitting more precise targeting of the radio signals. Most commonly referred to during space missions, these antennas are also in use all over Earth, most successfully in flat, open areas where there are no mountains to disrupt radiowaves. By contrast, a low-gain antenna (LGA) is an omnidirectional antenna with a broad radiowave beam width, that allows the signal to propagate reasonably well even in mountainous regions and is thus more reliable regardless of terrain. Low-gain antennas are often used in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orfordness Transmitting Station
The Orfordness transmitting station was a major radio broadcasting facility at Orford Ness on the Suffolk coast in the United Kingdom able to broadcast to much of Europe. It closed in May 2012 after more than 30 years of service. In 2017 Radio Caroline started broadcasting from the site, though not with the same intended coverage of an audience in Europe as the original station. The station was designed to transmit powerful medium wave ( AM) signals to much of Europe on two frequencies, 648 and 1296 kHz. Built by the British government, the facility passed through various owners after privatisation in 1997. From 2010, it was owned by a large engineering and defence services company, the Babcock International Group. The current owner of the site is a telecommunications company called Cobra Mist Limited, set up in 2015. Over the years, the Orfordness station carried a variety of radio services. It was best known, particularly in the UK, for transmitting the BBC World Service ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
