Band V (meaning Band 5) is the name of a radio frequency range within the ultra high frequency part of the electromagnetic spectrum.It is not to be confused with the V band in the extremely high frequency part of the spectrum.
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around twenty thousand times per second to around three hundred billion times per second. This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range.
Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter. Radio waves with frequencies above the UHF band fall into the super-high frequency (SHF) or microwave frequency range. Lower frequency signals fall into the VHF or lower bands. UHF radio waves propagate mainly by line of sight; they are blocked by hills and large buildings although the transmission through building walls is strong enough for indoor reception. They are used for television broadcasting, cell phones, satellite communication including GPS, personal radio services including Wi-Fi and Bluetooth, walkie-talkies, cordless phones, and numerous other applications.
The electromagnetic spectrum is the range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies.
Sources differ on the exact frequency range of UHF Band V. For example, the Broadcast engineer's reference book MHz and the DVB Worldwide website refers to the range as 585 to 806 MHz. Band V is primarily used for analogue and digital (DVB-T & ATSC) television broadcasting, as well as radio microphones and services intended for mobile devices such as DVB-H. With the close-down of analog television services most countries have auctioned off frequencies from 694 MHz and up to 4G cellular network providers.and the BBC define the range as 614 to 854 MHz. The IPTV India Forum define the range as 582 to 806
The British Broadcasting Corporation (BBC) is a British public service broadcaster. Its headquarters are at Broadcasting House in Westminster, London, and it is the world's oldest national broadcasting organisation and the largest broadcaster in the world by number of employees. It employs over 20,950 staff in total, 16,672 of whom are in public sector broadcasting. The total number of staff is 35,402 when part-time, flexible, and fixed-contract staff are included.
DVB-T is an abbreviation for "Digital Video Broadcasting — Terrestrial"; it is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in the UK in 1998. This system transmits compressed digital audio, digital video and other data in an MPEG transport stream, using coded orthogonal frequency-division multiplexing modulation. It is also the format widely used worldwide for Electronic News Gathering for transmission of video and audio from a mobile newsgathering vehicle to a central receive point.
Television (TV), sometimes shortened to tele or telly, is a telecommunication medium used for transmitting moving images in monochrome, or in colour, and in two or three dimensions and sound. The term can refer to a television set, a television program, or the medium of television transmission. Television is a mass medium for advertising, entertainment and news.
In Australia UHF channel allocations are 7 MHz wide. Band V includes channels 36 to 69, with base frequencies of 585.5 MHz to 816.5 MHz. More details are available on the television frequencies page.
Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands. It is the largest country in Oceania and the world's sixth-largest country by total area. The neighbouring countries are Papua New Guinea, Indonesia and East Timor to the north; the Solomon Islands and Vanuatu to the north-east; and New Zealand to the south-east. The population of 25 million is highly urbanised and heavily concentrated on the eastern seaboard. Australia's capital is Canberra, and its largest city is Sydney. The country's other major metropolitan areas are Melbourne, Brisbane, Perth and Adelaide.
Television frequency allocation has evolved since the start of television in Australia in 1956, and later in New Zealand in 1960. There was no coordination between the national spectrum management authorities in either country to establish the frequency allocations. The management of the spectrum in both countries is largely the product of their economical and political situation. New Zealand didn't start to develop television service until 1965 due to World War 2 and its economic harm in the country's economy.
In New Zealand UHF channel allocations are 8 MHz wide. Band V includes digital channels 36 to 49, with base frequencies of 594.0 MHz to 698.0 MHz. More details are available on the television frequencies page.
New Zealand is a sovereign island country in the southwestern Pacific Ocean. The country geographically comprises two main landmasses—the North Island, and the South Island —and around 600 smaller islands. New Zealand is situated some 2,000 kilometres (1,200 mi) east of Australia across the Tasman Sea and roughly 1,000 kilometres (600 mi) south of the Pacific island areas of New Caledonia, Fiji, and Tonga. Because of its remoteness, it was one of the last lands to be settled by humans. During its long period of isolation, New Zealand developed a distinct biodiversity of animal, fungal, and plant life. The country's varied topography and its sharp mountain peaks, such as the Southern Alps, owe much to the tectonic uplift of land and volcanic eruptions. New Zealand's capital city is Wellington, while its most populous city is Auckland.
In the UK, Band V allocations for television are 8 MHz wide, traditionally consisting of 30 channels from UHF 39 to 68 inclusive. There is also a channel 69, but in the UK, this is allocated to radio microphones. Semi-wideband aerials of the group E type cover this entire band. However, aerials of types group B and group C/D will cover the lower and upper halves of Band V respectively with higher gain than a group E.
The following table shows TV channel allocations in Band V in the UK.
The Office of Communications, commonly known as Ofcom, is the UK government-approved regulatory and competition authority for the broadcasting, telecommunications and postal industries of the United Kingdom.
Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF).
Amateur television (ATV) is the transmission of broadcast quality video and audio over the wide range of frequencies of radio waves allocated for radio amateur (Ham) use. ATV is used for non-commercial experimentation, pleasure, and public service events. Ham TV stations were on the air in many cities before commercial television stations came on the air. Various transmission standards are used, these include the broadcast transmission standards of NTSC in North America and Japan, and PAL or SECAM elsewhere, utilizing the full refresh rates of those standards. ATV includes the study of building of such transmitters and receivers, and the study of radio propagation of signals travelling between transmitting and receiving stations.
The radio spectrum is the part of the electromagnetic spectrum with frequencies from 30 Hertz to 300 GHz. Electromagnetic waves in this frequency range, called radio waves, are extremely widely used in modern technology, particularly in telecommunication. To prevent interference between different users, the generation and transmission of radio waves is strictly regulated by national laws, coordinated by an international body, the International Telecommunication Union (ITU).
The following tables show the frequencies assigned to broadcast television channels in various regions of the world, along with the ITU letter designator for the system used. The frequencies shown are for the analogue video and audio carriers. The channel itself occupies several megahertz of bandwidth. For example, North American channel 2 occupies the spectrum from 54 to 60 MHz. See Broadcast television systems for a table of signal characteristics, including bandwidth, by ITU letter designator.
In North American broadcast television frequencies, channel 1 is a former broadcast (over-the-air) television channel. During the experimental era of TV operation, Channel 1 was moved around the lower VHF spectrum repeatedly, with the entire band displaced upward at one point due to an early 40 MHz allocation for the FM broadcast band.
Digital terrestrial television in the United Kingdom encompasses over 100 television, radio and interactive services broadcast via the United Kingdom's terrestrial television network and receivable with a standard television set. The majority of digital terrestrial television (DTT) services, including the five former analogue channels, are broadcast free-to-air, and a further selection of encrypted pay TV services are also available.
The Wenvoe transmitting station is a facility for broadcasting and telecommunications situated close to the village of Wenvoe in the Vale of Glamorgan, Wales, in the UK. It comprises a 260.7-metre (855 ft) guyed mast with antennas attached at various heights. The mast plus the Main UHF (TV) antenna on top gives a height of 260.7 metres (869 ft). The average height above sea level is 392 metres for the television antennas. It is owned and operated by Arqiva. The mast sways 10 feet, or 4 meters, which is quite high for a mast this size.
A spectrum auction is a process whereby a government uses an auction system to sell the rights (licenses) to transmit signals over specific bands of the electromagnetic spectrum and to assign scarce spectrum resources. Depending on the specific auction format used, a spectrum auction can last from a single day to several months from the opening bid to the final winning bid. With a well-designed auction, resources are allocated efficiently to the parties that value them the most, the government securing revenue in the process. Spectrum auctions are a step toward market-based spectrum management and privatization of public airwaves, and are a way for governments to allocate scarce resources. Alternatives to auctions include administrative licensing, such as the comparative hearings conducted historically, or lotteries.
Channel 37 is a purposefully unused ultra-high frequency (UHF) television broadcasting television channel in the United States, Canada and Mexico. The frequency range allocated to this channel is important for radio astronomy, so broadcasting is not licensed.
A wireless microphone, or cordless microphone, is a microphone without a physical cable connecting it directly to the sound recording or amplifying equipment with which it is associated. Also known as a radio microphone, it has a small, battery-powered radio transmitter in the microphone body, which transmits the audio signal from the microphone by radio waves to a nearby receiver unit, which recovers the audio. The other audio equipment is connected to the receiver unit by cable. In one type the transmitter is contained within the handheld microphone body. In another type, called a "lavalier microphone" or "lav", a small microphone clipped to the user's lapel is connected by wire to a transmitter unit concealed under his clothes. In a third type the transmitter is a headset, with a microphone on a boom extending in front of the user's mouth. Wireless microphones are widely used in the entertainment industry, television broadcasting, and public speaking to allow public speakers, interviewers, performers, and entertainers to move about freely while using a microphone without requiring a cable attached to the microphone.
The Oxford transmitting station is a broadcasting and telecommunications facility, situated on land 129.5 metres (425 ft) above Ordnance Datum to the north east of the city of Oxford, in Oxfordshire, England. It has a guyed steel lattice mast which is 154.4 metres (507 ft) in height to the top of the main steel structure. The UHF television antenna, which consist of a vertical array of transmitting panels, is mounted above the steel structure. The total height of the mast to the top of this UHF antenna is 165.7 metres (544 ft). It is owned and operated by Arqiva.
Band III is the name of the range of radio frequencies within the very high frequency (VHF) part of the electromagnetic spectrum from 174 to 240 megahertz (MHz). It is primarily used for radio and television broadcasting. It is also called high-band VHF, in contrast to Bands I and II.
In telecommunications, white spaces refer to frequencies allocated to a broadcasting service but not used locally.
The United States 700 MHz FCC wireless spectrum auction, officially known as Auction 73, was started by the Federal Communications Commission (FCC) on January 24, 2008 for the rights to operate the 700 MHz radio frequency band in the United States. The details of process were the subject of debate among several telecommunications companies, including Verizon Wireless, AT&T Mobility, as well as the Internet company Google. Much of the debate swirled around the "open access" requirements set down by the Second Report and Order released by the FCC determining the process and rules for the auction. All bidding was required by law to commence by January 28.
Band IV is the name of a radio frequency range within the ultra high frequency part of the electromagnetic spectrum.
The digital dividend refers to the radio spectrum which is released in the process of digital television transition. When television broadcasters switch from analog TV to digital-only platforms, part of the electromagnetic spectrum that has been used for broadcasting will be freed-up because digital television needs less spectrum than analog television. One reason is that new digital video compression technology can transmit numerous digital subchannels using the same amount of spectrum used to transmit one analog TV channel. However, the primary reason is that digital transmissions require much less of a guard band on either side, since they are not nearly as prone to RF interference from adjacent channels. Because of this, there is no longer any need to leave empty channels to protect stations from each other, in turn allowing stations to be repacked into fewer channels, leaving more contiguous spectrum to be allocated for other wireless services.
The Pan-American television frequencies are different for terrestrial and cable television systems. Terrestrial television channels are divided into two bands: the VHF band which comprises channels 2 through 13 and occupies frequencies between 54 through 216 MHz, and the UHF band, which comprises channels 14 through 83 and occupies frequencies between 470 and 890 MHz. These bands are different enough in frequency that they often require separate antennas to receive, and separate tuning controls on the television set. The VHF band is further divided into two frequency ranges: VHF low band between 54 and 88 MHz, containing channels 2 through 6, and VHF high band between 174 and 216 MHz, containing channels 7 through 13. The wide spacing between these frequency bands is responsible for the complicated design of rooftop TV antennas. The UHF band has higher noise and greater attenuation, so higher gain antennas are often required for UHF.
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