词条 | Radio communication station |
释义 |
A radio communication station is a set of equipment necessary to carry on communication via radio waves. Generally, it is a receiver or transmitter or transceiver, an antenna, and some smaller additional equipment necessary to operate them. They play a vital role in communication technology as they are heavily relied on to transfer data and information across the world.[1] More broadly, the definition of a radio station includes the aforementioned equipment and a building in which it is installed. Such a station may include several "radio stations" defined above (i.e. several sets of receivers or transmitters installed in one building but functioning independently, and several antennas installed on a field next to the building). This definition of a radio station is more often referred to as a transmitter site, transmitter station, transmission facility or transmitting station. An example of this definition is Bethany Relay Station of the Voice of America which had seven broadcast transmitters and could broadcast up to seven independent programs (even produced by different broadcasters) simultaneously, as well as several communications transmitters and receivers. ITU definitionThe International Telecommunications Union, defines a radio (communication) station as - «one or more transmitters or receivers or a combination of transmitters and receivers, including the accessory equipment, necessary at one location for carrying on a radio communication service, or the radio astronomy service. Each station shall be classified by the service in which it operates permanently or temporarily».[2] Equipment
These are the most used/important devices and items for most radio stations. AntennasA microphone is used to capture the input of sound waves created by people speaking into the device. The sounds are then turned into electrical energy; this energy then flows along a metal antenna. As the electrons in the electric current move back and forth up the antenna, the current creates an invisible electromagnetic radiation in the form of radio waves. The waves travel at the speed of light, taking the radio program (voices recorded) with them.[4] TransceiverA compound of both a transmitter and a receiver is called a transceiver, they are combined and share common circuitry or a single housing. Technically transceivers must combine a significant amount of the transmitter and receiver handling the circuitry. Radio frequency listPossible Frequency allocations, allotments & assignments
References1. ^{{Cite web|title = What is ICT (information and communications technology - or technologies)? - Definition from WhatIs.com|url = http://searchcio.techtarget.com/definition/ICT-information-and-communications-technology-or-technologies|website = SearchCIO|accessdate = 2015-11-04}} {{Radio station ITU}}{{Authority control}}2. ^{{Cite web|title = Radio Regulations, Articles, Edition of 2012|url = http://www.itu.int/dms_pub/itu-s/oth/02/02/S02020000244501PDFE.PDF|website = ITU}} 3. ^{{Cite web|title = Equipment for a Radio Station {{!}} Complete List {{!}} Radio Broadcasting|url = http://familypsalms.com/equipment/|website = familypsalms.com|accessdate = 2015-11-04}} 4. ^{{Cite web|title = How do antennas and transmitters work? - Explain that Stuff|url = http://www.explainthatstuff.com/antennas.html|website = www.explainthatstuff.com|accessdate = 2015-11-03}} 5. ^{{Cite web|url=http://www.arrl.org/frequency-allocations|title=Frequency Allocations|website=www.arrl.org|language=en|access-date=2017-07-09}} 6. ^{{Cite web|title = How the Radio Spectrum Works|url = http://electronics.howstuffworks.com/radio-spectrum1.htm|website = HowStuffWorks|accessdate = 2015-11-04}} 3 : Radio stations and systems ITU|Radio|Radio stations |
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