Radio spectrum
Encyclopedia
Radio spectrum refers to the part of the electromagnetic spectrum
corresponding to radio frequencies – that is, frequencies lower than around 300 GHz (or, equivalently, wavelengths longer than about 1 mm).
Different parts of the radio spectrum are used for different radio transmission technologies and applications. Radio spectrum is typically government regulated in developed countries and, in some cases, is sold or licensed to operators of private radio transmission systems (for example, cellular telephone operators or broadcast television stations). Ranges of allocated frequencies are often referred to by their provisioned use (for example, cellular spectrum or television spectrum).
of radio
communication frequencies
, in which channels
are usually used or set aside for the same purpose.
Above 300 GHz, the absorption of electromagnetic radiation
by Earth's atmosphere is so great that the atmosphere is effectively opaque, until it becomes transparent again in the near-infrared
and optical window frequency ranges.
To prevent interference and allow for efficient use of the radio spectrum, similar services are allocated in bands. For example, broadcasting, mobile radio, or navigation devices, will be allocated in non-overlapping ranges of frequencies.
Each of these bands has a basic bandplan
which dictates how it is to be used and shared, to avoid interference
and to set protocol
for the compatibility of transmitter
s and receiver
s.
As a matter of convention, bands are divided at wavelength
s of 10n metres, or frequencies of 3×10n hertz
. For example, 30 MHz or 10 m divides shortwave (lower and longer) from VHF (shorter and higher). These are the parts of the radio spectrum, and not its frequency allocation
.
Radio Regulations
. Article 2, provision No. 2.1 states that "the radio spectrum shall be subdivided into nine frequency bands, which shall be designated by progressive whole numbers in accordance with the following table".
The table originated with a recommendation of the IVth CCIR meeting, held in Bucharest in 1937, and was approved by the International Radio Conference held at Atlantic City in 1947. The idea to give each band a number, in which the number is the logarithm of the approximate geometric mean of the upper and lower band limits in Hz, originated with B.C. Fleming-Williams, who suggested it in a letter to the editor of Wireless Engineer in 1942. (For example, the approximate geometric mean of Band 7 is 10 MHz, or 107 Hz.)
† This column does not form part of the table in Provision No. 2.1 of the Radio Regulations
Designations for television and FM radio broadcast frequencies vary between countries, see Television channel frequencies
and FM broadcast band
. Since VHF and UHF frequencies are desirable for many uses in urban areas, in North America some parts of the former television broadcasting band have been reassigned to cellular phone and various land mobile communications systems. Even within the allocation still dedicated to television, TV-band device
s use channels without local broadcasters.
The Apex
band in the United States was a pre-WWII allocation for VHF audio broadcasting; it was made obsolete after the introduction of FM broadcasting.
refers to VHF frequencies used for navigation and voice communication with aircraft. Trans-oceanic aircraft also carry HF
radio and satellite transceivers.
is a medium-wave frequency still used for marine emergency communication.
Marine VHF radio
is used in coastal waters and relatively short-range communication between vessels and to shore stations. Radios are channelized, with different channels used for different purposes; marine Channel 16 is used for calling and emergencies.
vary around the world. Several bands are common for amateurs world-wide, usually in the shortwave part of the spectrum. Other bands are national or regional allocations only due to differing allocations for other services, especially in the VHF and UHF parts of the radio spectrum.
is allocated in many countries, using channelized radios in the upper HF part of the spectrum (around 27 MHz). It used for personal, small business and hobby purposes. Other frequency allocations are used for similar services in different jurisdictions, for example UHF CB
is allocated in Australia. A wide range of personal radio services
exist around the world, usually emphasizing short-range communication between individuals or for small businesses, simplified or no license requirements, and usually FM transceivers using around 1 watt or less.
s were initially reserved for non-communications uses of RF energy, such as microwave oven
s, radio-frequency heating, and similar purposes. Many unlicensed devices such as cordless telephones or wireless computer networks now use ISM frequencies, with no expectation of regulatory protection from primary ISM devices.
s and land mobile vehicle-mounted or portable
transceivers. In the United States these services are informally known as business band
radio. See also Professional mobile radio
.
Police radio
and other public safety services such as fire departments and ambulances are generally found in the VHF and UHF parts of the spectrum. Trunking
systems are often used to make most efficient use of the limited number of frequencies available.
The demand for mobile telephone service has led to large blocks of radio spectrum allocated to cellular frequencies
.
uses bands dedicated to the purpose. Radio-controlled toys may use portions of unlicensed spectrum in the 27 MHz or 49 MHz bands, but more costly aircraft, boat, or land vehicle models use dedicated remote control frequencies near 72 MHz to avoid interference by unlicensed uses. Licensed amateur radio operators use portions of the 6-meter band
in North America. Industrial remote control of cranes or railway locomotives use assigned frequencies that vary by area.
applications use relatively high power pulse transmitters and sensitive receivers, so radar is operated on bands not used for other purposes. Most radar bands are in the microwave
part of the spectrum, although certain important applications for meteorology
make use of powerful transmitters in the UHF band.
Electromagnetic spectrum
The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....
corresponding to radio frequencies – that is, frequencies lower than around 300 GHz (or, equivalently, wavelengths longer than about 1 mm).
Different parts of the radio spectrum are used for different radio transmission technologies and applications. Radio spectrum is typically government regulated in developed countries and, in some cases, is sold or licensed to operators of private radio transmission systems (for example, cellular telephone operators or broadcast television stations). Ranges of allocated frequencies are often referred to by their provisioned use (for example, cellular spectrum or television spectrum).
By frequency
A band is a small section of the spectrumElectromagnetic spectrum
The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....
of radio
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
communication frequencies
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
, in which channels
Channel (communications)
In telecommunications and computer networking, a communication channel, or channel, refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel...
are usually used or set aside for the same purpose.
Above 300 GHz, the absorption of electromagnetic radiation
Electromagnetic radiation
Electromagnetic radiation is a form of energy that exhibits wave-like behavior as it travels through space...
by Earth's atmosphere is so great that the atmosphere is effectively opaque, until it becomes transparent again in the near-infrared
Infrared
Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...
and optical window frequency ranges.
To prevent interference and allow for efficient use of the radio spectrum, similar services are allocated in bands. For example, broadcasting, mobile radio, or navigation devices, will be allocated in non-overlapping ranges of frequencies.
Each of these bands has a basic bandplan
Bandplan
A bandplan or band plan is a plan for using a particular band of radio frequencies, that are a portion of the electromagnetic spectrum . Each bandplan defines the frequency range to be included, how channels are to be defined, and what will be carried on those channels...
which dictates how it is to be used and shared, to avoid interference
Co-channel interference
Co-channel interference or CCI is crosstalk from two different radio transmitters using the same frequency. There can be several causes of co-channel radio interference; four examples are listed here....
and to set protocol
Communications protocol
A communications protocol is a system of digital message formats and rules for exchanging those messages in or between computing systems and in telecommunications...
for the compatibility of transmitter
Transmitter
In electronics and telecommunications a transmitter or radio transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating...
s and receiver
Receiver (radio)
A radio receiver converts signals from a radio antenna to a usable form. It uses electronic filters to separate a wanted radio frequency signal from all other signals, the electronic amplifier increases the level suitable for further processing, and finally recovers the desired information through...
s.
As a matter of convention, bands are divided at wavelength
Wavelength
In physics, the wavelength of a sinusoidal wave is the spatial period of the wave—the distance over which the wave's shape repeats.It is usually determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a...
s of 10n metres, or frequencies of 3×10n hertz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
. For example, 30 MHz or 10 m divides shortwave (lower and longer) from VHF (shorter and higher). These are the parts of the radio spectrum, and not its frequency allocation
Frequency allocation
Use of radio frequency bands of the electromagnetic spectrum is regulated by governments in most countries, in a Spectrum management process known as frequency allocation or spectrum allocation. Radio propagation does not stop at national boundaries...
.
| Band name | Abbr Abbreviation An abbreviation is a shortened form of a word or phrase. Usually, but not always, it consists of a letter or group of letters taken from the word or phrase... |
ITU band | Frequency and wavelength in air |
Example uses |
|---|---|---|---|---|
| < 3 Hz Hertz The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications.... > 100,000 km |
Natural and man-made electromagnetic noise | |||
| Extremely low frequency Extremely low frequency Extremely low frequency is a term used to describe radiation frequencies from 3 to 300 Hz. In atmosphere science, an alternative definition is usually given, from 3 Hz to 3 kHz... |
ELF | 1 | 3–30 Hz 100,000 km – 10,000 km |
Communication with submarines Communication with submarines Communication with submarines is difficult because radio waves do not travel well through thick electrical conductors like salt water.The obvious solution is to surface and raise an antenna above the water, then use ordinary radio transmissions. Early submarines had to frequently surface anyway for... |
| Super low frequency Super low frequency Super-low frequency is the frequency range between 30 hertz and 300 hertz. This frequency range includes the frequencies of AC power grids .... |
SLF | 2 | 30–300 Hz 10,000 km – 1000 km |
Communication with submarines |
| Ultra low frequency Ultra low frequency Ultra-low frequency is the frequency range of electromagnetic waves between 300 hertz and 3 kilohertz. In magnetosphere science and seismology, alternative definitions are usually given, including ranges from 1 mHz to 100 Hz, 1 mHz to 1 Hz, 10 mHz to 10 Hz... |
ULF | 3 | 300–3000 Hz 1000 km – 100 km |
Submarine communication, Communication within mines Through the earth mine communications Through-the-Earth signalling is a type of radio signalling used in underground mines that uses low frequency waves to penetrate dirt and rock, which are opaque to higher-frequency conventional radio signals.... |
| Very low frequency Very low frequency 225px|thumb|right|A VLF receiving antenna at [[Palmer Station]], Antarctica, operated by Stanford UniversityVery low frequency or VLF refers to radio frequencies in the range of 3 kHz to 30 kHz. Since there is not much bandwidth in this band of the radio spectrum, only the very simplest signals... |
VLF | 4 | 3–30 kHz 100 km – 10 km |
Navigation Radio navigation Radio navigation or radionavigation is the application of radio frequencies to determine a position on the Earth. Like radiolocation, it is a type of radiodetermination.The basic principles are measurements from/to electric beacons, especially... , time signals Radio clock A radio clock or radio-controlled clock is a clock that is synchronized by a time code bit stream transmitted by a radio transmitter connected to a time standard such as an atomic clock... , submarine communication, wireless heart rate monitor Heart rate monitor A heart rate monitor is a personal monitoring device which allows a subject to measure his or her heart rate in real time or record his or her heart rate for later study... s, geophysics Geophysics Geophysics is the physics of the Earth and its environment in space; also the study of the Earth using quantitative physical methods. The term geophysics sometimes refers only to the geological applications: Earth's shape; its gravitational and magnetic fields; its internal structure and... |
| Low frequency Low frequency Low frequency or low freq or LF refers to radio frequencies in the range of 30 kHz–300 kHz. In Europe, and parts of Northern Africa and of Asia, part of the LF spectrum is used for AM broadcasting as the longwave band. In the western hemisphere, its main use is for aircraft beacon,... |
LF | 5 | 30–300 kHz 10 km – 1 km |
Navigation, time signals, AM longwave Longwave In radio, longwave refers to parts of radio spectrum with relatively long wavelengths. The term is a historic one dating from the early 20th century, when the radio spectrum was considered to consist of long, medium and short wavelengths... broadcasting (Europe and parts of Asia), RFID, amateur radio Amateur radio Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication... |
| Medium frequency Medium frequency Medium frequency refers to radio frequencies in the range of 300 kHz to 3 MHz. Part of this band is the medium wave AM broadcast band. The MF band is also known as the hectometer band or hectometer wave as the wavelengths range from ten down to one hectometers... |
MF | 6 | 300–3000 kHz 1 km – 100 m |
AM (medium-wave) broadcasts, amateur radio, avalanche beacons |
| High frequency High frequency High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency... |
HF | 7 | 3–30 MHz 100 m – 10 m |
Shortwave Shortwave Shortwave radio refers to the upper MF and all of the HF portion of the radio spectrum, between 1,800–30,000 kHz. Shortwave radio received its name because the wavelengths in this band are shorter than 200 m which marked the original upper limit of the medium frequency band first used... broadcasts, citizens' band radio Citizens' band radio Citizens' Band radio is, in many countries, a system of short-distance radio communications between individuals on a selection of 40 channels within the 27-MHz band. Citizens' Band is distinct from the FRS, GMRS, MURS and amateur radio... , amateur radio and over-the-horizon aviation communications, RFID, Over-the-horizon radar Over-the-horizon radar Over-the-horizon radar, or OTH , is a design concept for radar systems to allow them to detect targets at very long ranges, typically up to thousands of kilometers... , Automatic link establishment Automatic link establishment Automatic Link Establishment, commonly known as ALE, is the worldwide de facto standard for digitally initiating and sustaining HF radio communications. ALE is a feature in an HF communications radio transceiver system, that enables the radio station to make contact, or initiate a circuit, between... (ALE) / Near Vertical Incidence Skywave Near Vertical Incidence Skywave Near Vertical Incidence Skywave, or NVIS, is a radio-wave propagation method that provides usable signals in the range between groundwave and skywave distances . It is used mainly for military and paramilitary communications and by radio amateurs... (NVIS) radio communications, Marine and mobile radio telephony Marine and mobile radio telephony The Marine Radiotelephone Service or HF ship-to-shore operates on shortwave radio frequencies, using single-sideband modulation. The usual method is that a ship calls a shore station, and the shore station's marine operator connects the caller to the public switched telephone network... |
| Very high frequency Very high frequency Very high frequency is the radio frequency range from 30 MHz to 300 MHz. Frequencies immediately below VHF are denoted High frequency , and the next higher frequencies are known as Ultra high frequency... |
VHF | 8 | 30–300 MHz 10 m – 1 m |
FM, television Television Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound... broadcasts and line-of-sight ground-to-aircraft and aircraft-to-aircraft communications. Land Mobile and Maritime Mobile communications, amateur radio, weather radio |
| Ultra high frequency Ultra high frequency Ultra-High Frequency designates the ITU Radio frequency range of electromagnetic waves between 300 MHz and 3 GHz , also known as the decimetre band or decimetre wave as the wavelengths range from one to ten decimetres... |
UHF | 9 | 300–3000 MHz 1 m – 100 mm |
Television broadcasts, microwave Microwave Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries... ovens, microwave devices/communications, radio astronomy Radio astronomy Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of... , mobile phone Mobile phone A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator... s, wireless LAN Wireless LAN A wireless local area network links two or more devices using some wireless distribution method , and usually providing a connection through an access point to the wider internet. This gives users the mobility to move around within a local coverage area and still be connected to the network... , Bluetooth Bluetooth Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances from fixed and mobile devices, creating personal area networks with high levels of security... , ZigBee ZigBee ZigBee is a specification for a suite of high level communication protocols using small, low-power digital radios based on an IEEE 802 standard for personal area networks. Applications include wireless light switches, electrical meters with in-home-displays, and other consumer and industrial... , GPS and two-way radios such as Land Mobile, FRS Family Radio Service The Family Radio Service is an improved walkie talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies in the ultra high frequency band. It does not suffer the interference effects found on citizens' band at 27 MHz, or the... and GMRS radios, amateur radio |
| Super high frequency Super high frequency Super high frequency refers to radio frequencies in the range of 3 GHz and 30 GHz. This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from ten to one centimetres.... |
SHF | 10 | 3–30 GHz 100 mm – 10 mm |
radio astronomy, microwave devices/communications, wireless LAN, most modern radar Radar Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio... s, communications satellite Communications satellite A communications satellite is an artificial satellite stationed in space for the purpose of telecommunications... s, satellite television broadcasting, DBS, amateur radio |
| Extremely high frequency Extremely high frequency Extremely high frequency is the highest radio frequency band. EHF runs the range of frequencies from 30 to 300 gigahertz, above which electromagnetic radiation is considered to be low infrared light, also referred to as terahertz radiation... |
EHF | 11 | 30–300 GHz 10 mm – 1 mm |
radio astronomy, high-frequency microwave radio relay, microwave remote sensing Remote sensing Remote sensing is the acquisition of information about an object or phenomenon, without making physical contact with the object. In modern usage, the term generally refers to the use of aerial sensor technologies to detect and classify objects on Earth by means of propagated signals Remote sensing... , amateur radio, directed-energy weapon Active Denial System The Active Denial System is a non-lethal, directed-energy weapon developed by the U.S. military. It is a strong millimeter-wave transmitter primarily used for crowd control . Some ADS such as HPEM ADS are also used to disable vehicles. Informally, the weapon is also called the heat ray... , millimeter wave scanner Millimeter wave scanner A millimeter wave scanner is a whole–body imaging device used for detecting objects concealed underneath a person’s clothing. Typical uses for this technology include detection of items for commercial loss prevention, smuggling and screening at government buildings and airport security... |
| Terahertz or Tremendously high frequency Tremendously high frequency Tremendously high frequency is a band designation used by some authors to refer to a decade band in the submillimeter radiation/terahertz radiation range. It follows the ITU EHF band in increasing frequency order.... |
THz or THF | 12 | 300–3,000 GHz 1 mm – 100 m |
Terahertz imaging – a potential replacement for X-rays in some medical applications, ultrafast molecular dynamics, condensed-matter physics, terahertz time-domain spectroscopy, terahertz computing/communications, sub-mm remote sensing, amateur radio |
ITU
The ITU radio bands are designations defined in the ITUItu
Itu is an old and historic municipality in the state of São Paulo in Brazil. The population in 2009 was 157,384 and the area is 641.68 km². The elevation is 583 m. This place name comes from the Tupi language, meaning big waterfall. Itu is linked with the highway numbered the SP-75 and are flowed...
Radio Regulations
Radio Regulations
The Radio Regulations is an intergovernmental treaty text of the International Telecommunication Union , the Geneva-based specialised agency of the United Nations which coordinates and standardises the operation of telecommunication networks and services and advances the development of...
. Article 2, provision No. 2.1 states that "the radio spectrum shall be subdivided into nine frequency bands, which shall be designated by progressive whole numbers in accordance with the following table".
The table originated with a recommendation of the IVth CCIR meeting, held in Bucharest in 1937, and was approved by the International Radio Conference held at Atlantic City in 1947. The idea to give each band a number, in which the number is the logarithm of the approximate geometric mean of the upper and lower band limits in Hz, originated with B.C. Fleming-Williams, who suggested it in a letter to the editor of Wireless Engineer in 1942. (For example, the approximate geometric mean of Band 7 is 10 MHz, or 107 Hz.)
| Band Number | Symbols | Frequency Range | Wavelength Range† |
|---|---|---|---|
| 4 | VLF Very low frequency 225px|thumb|right|A VLF receiving antenna at [[Palmer Station]], Antarctica, operated by Stanford UniversityVery low frequency or VLF refers to radio frequencies in the range of 3 kHz to 30 kHz. Since there is not much bandwidth in this band of the radio spectrum, only the very simplest signals... |
3 to 30 kHz | 10 to 100 km |
| 5 | LF Low frequency Low frequency or low freq or LF refers to radio frequencies in the range of 30 kHz–300 kHz. In Europe, and parts of Northern Africa and of Asia, part of the LF spectrum is used for AM broadcasting as the longwave band. In the western hemisphere, its main use is for aircraft beacon,... |
30 to 300 kHz | 1 to 10 km |
| 6 | MF Medium frequency Medium frequency refers to radio frequencies in the range of 300 kHz to 3 MHz. Part of this band is the medium wave AM broadcast band. The MF band is also known as the hectometer band or hectometer wave as the wavelengths range from ten down to one hectometers... |
300 to 3000 kHz | 100 to 1000 m |
| 7 | HF High frequency High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency... |
3 to 30 MHz | 10 to 100 m |
| 8 | VHF Very high frequency Very high frequency is the radio frequency range from 30 MHz to 300 MHz. Frequencies immediately below VHF are denoted High frequency , and the next higher frequencies are known as Ultra high frequency... |
30 to 300 MHz | 1 to 10 m |
| 9 | UHF Ultra high frequency Ultra-High Frequency designates the ITU Radio frequency range of electromagnetic waves between 300 MHz and 3 GHz , also known as the decimetre band or decimetre wave as the wavelengths range from one to ten decimetres... |
300 to 3000 MHz | 10 to 100 cm |
| 10 | SHF Super high frequency Super high frequency refers to radio frequencies in the range of 3 GHz and 30 GHz. This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from ten to one centimetres.... |
3 to 30 GHz | 1 to 10 cm |
| 11 | EHF Extremely high frequency Extremely high frequency is the highest radio frequency band. EHF runs the range of frequencies from 30 to 300 gigahertz, above which electromagnetic radiation is considered to be low infrared light, also referred to as terahertz radiation... |
30 to 300 GHz | 1 to 10 mm |
| 12 | 300 to 3000 GHz | | 0.1 to 1 mm | |
† This column does not form part of the table in Provision No. 2.1 of the Radio Regulations
IEEE US
| Band | Frequency range | |
|---|---|---|
| HF band High frequency High frequency radio frequencies are between 3 and 30 MHz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters . Frequencies immediately below HF are denoted Medium-frequency , and the next higher frequencies are known as Very high frequency... |
3 to 30 MHz | High Frequency |
| VHF band | 30 to 300 MHz | Very High Frequency |
| UHF band | 300 to 1000 MHz | Ultra High Frequency |
| L band L band L band refers to four different bands of the electromagnetic spectrum: 40 to 60 GHz , 1 to 2 GHz , 1565 nm to 1625 nm , and around 3.5 micrometres .-NATO L band:... |
1 to 2 GHz | Long wave |
| S band S band The S band is defined by an IEEE standard for radio waves with frequencies that range from 2 to 4 GHz, crossing the conventional boundary between UHF and SHF at 3.0 GHz. It is part of the microwave band of the electromagnetic spectrum... |
2 to 4 GHz | Short wave |
| C band C band The C band is a name given to certain portions of the electromagnetic spectrum, including wavelengths of microwaves that are used for long-distance radio telecommunications. The IEEE C-band - and its slight variations - contains frequency ranges that are used for many satellite communications... |
4 to 8 GHz | Compromise between S and X |
| X band X band The X band is a segment of the microwave radio region of the electromagnetic spectrum. In some cases, such as in communication engineering, the frequency range of X band is rather indefinitely set at approximately 7.0 to 11.2 gigahertz . In radar engineering, the frequency range is specified... |
8 to 12 GHz | Used in WW II World War II World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis... for fire control Fire-control system A fire-control system is a number of components working together, usually a gun data computer, a director, and radar, which is designed to assist a weapon system in hitting its target. It performs the same task as a human gunner firing a weapon, but attempts to do so faster and more... , X for cross (as in crosshair Crosshair A reticle is a net of fine lines or fibers in the eyepiece of a sighting device, such as a telescope, a telescopic sight, a microscope, or the screen of an oscilloscope. The word reticle comes from the Latin "reticulum," meaning "net." Today, engraved lines or embedded fibers may be replaced by a... ) |
| Ku band Ku band The Kμ band is a portion of the electromagnetic spectrum in the microwave range of frequencies. This symbol refers to —in other words, the band directly below the K-band... |
12 to 18 GHz | Kurz-under |
| K band K band K band designates certain portions of the electromagnetic spectrum, in either the microwave domain or in the infrared domain. The microwave K bands are used primarily for radar and satellite communications while the infrared K band is used for astronomical observations.-NATO K band:The NATO K band... |
18 to 27 GHz | German German language German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union.... Kurz (short) |
| Ka band Ka band The Ka band covers the frequencies of 26.5–40 GHz. The Ka band is part of the K band of the microwave band of the electromagnetic spectrum. This symbol refers to "K-above" — in other words, the band directly above the K-band... |
27 to 40 GHz | Kurz-above |
| V band V band The V band of the electromagnetic spectrum ranges from 50 to 75 GHz. The V band is not heavily used, except for millimeter wave radar research and other kinds of scientific research... |
40 to 75 GHz | |
| W band W band The W band of the microwave part of the electromagnetic spectrum ranges from 75 to 110 GHz. It sits above the U.S. IEEE designated V band in frequency, yet overlaps the NATO designated M band... |
75 to 110 GHz | W follows V in the alphabet Alphabet An alphabet is a standard set of letters—basic written symbols or graphemes—each of which represents a phoneme in a spoken language, either as it exists now or as it was in the past. There are other systems, such as logographies, in which each character represents a word, morpheme, or semantic... |
| mm band | 110 to 300 GHz |
EU, NATO, US ECM frequency designations
| Band | Frequency range |
|---|---|
| A band | 0 to 0.25 GHz |
| B band B band The B band is the range of radio frequencies from 250 MHz to 500 MHz in the electromagnetic spectrum. This is equal to wave lengths between 1.2 m and 0.6 m. The B band is in the VHF/UHF range of the radio spectrum.... |
0.25 to 0.5 GHz |
| C band C band The C band is a name given to certain portions of the electromagnetic spectrum, including wavelengths of microwaves that are used for long-distance radio telecommunications. The IEEE C-band - and its slight variations - contains frequency ranges that are used for many satellite communications... |
0.5 to 1.0 GHz |
| D band D band IEEE D band is the range of radio frequencies from 110 GHz to 170 GHz in the electromagnetic spectrum. This is equal to wave lengths between 1.8 mm and 2.7 mm... |
1 to 2 GHz |
| E band E band The NATO E band is the range of radio frequencies from 2 GHz to 3 GHz in the electromagnetic spectrum. This is equal to wave lengths between 15 cm and 10 cm. The E band is in the upper UHF range of the radio spectrum... |
2 to 3 GHz |
| F band F band The F band is the range of radio frequencies from 90 GHz to 140 GHz in the electromagnetic spectrum. This is equal to wave lengths between 2.1 mm and 3.3 mm... |
3 to 4 GHz |
| G band G band -NATO G band:The G band in the modern sense is the range of radio frequencies from 4 GHz to 6 GHz in the electromagnetic spectrum. This is equal to wave lengths between 7.5 cm and 5 cm... |
4 to 6 GHz |
| H band H band H band can refer to two different regions of the electromagnetic spectrum, in the radio and near-infrared.-Radio:The H band is the range of radio frequencies from 6 GHz to 8 GHz in the electromagnetic spectrum. This is equal to wave lengths between 5 cm and 3.75 cm... |
6 to 8 GHz |
| I band I band The I band is the range of radio frequencies from 8 GHz to 10 GHz in the electromagnetic spectrum. This is equal to wave lengths between 3.75 cm and 3 cm. The I band is in the SHF range of the radio spectrum.... |
8 to 10 GHz |
| J band J band J band can refer to two different regions of the electromagnetic spectrum, in the radio and near-infrared.-Radio:The J band is the range of radio frequencies from 10 GHz to 20 GHz in the electromagnetic spectrum. This is equal to wave lengths between... |
10 to 20 GHz |
| K band K band K band designates certain portions of the electromagnetic spectrum, in either the microwave domain or in the infrared domain. The microwave K bands are used primarily for radar and satellite communications while the infrared K band is used for astronomical observations.-NATO K band:The NATO K band... |
20 to 40 GHz |
| L band L band L band refers to four different bands of the electromagnetic spectrum: 40 to 60 GHz , 1 to 2 GHz , 1565 nm to 1625 nm , and around 3.5 micrometres .-NATO L band:... |
40 to 60 GHz |
| M band M band M band can refer to two different regions of the electromagnetic spectrum, in the radio and near-infrared.-Radio:The M band is the range of radio frequencies from 60 GHz to 100 GHz in the electromagnetic spectrum. This is equal to wave lengths between 5 mm and 3 mm... |
60 to 100 GHz |
Waveguide frequency bands
| Band | Frequency range |
|---|---|
| R band | 1.70 to 2.60 GHz |
| D band D band IEEE D band is the range of radio frequencies from 110 GHz to 170 GHz in the electromagnetic spectrum. This is equal to wave lengths between 1.8 mm and 2.7 mm... |
2.20 to 3.30 GHz |
| S band S band The S band is defined by an IEEE standard for radio waves with frequencies that range from 2 to 4 GHz, crossing the conventional boundary between UHF and SHF at 3.0 GHz. It is part of the microwave band of the electromagnetic spectrum... |
2.60 to 3.95 GHz |
| E band E band The NATO E band is the range of radio frequencies from 2 GHz to 3 GHz in the electromagnetic spectrum. This is equal to wave lengths between 15 cm and 10 cm. The E band is in the upper UHF range of the radio spectrum... |
3.30 to 4.90 GHz |
| G band G band -NATO G band:The G band in the modern sense is the range of radio frequencies from 4 GHz to 6 GHz in the electromagnetic spectrum. This is equal to wave lengths between 7.5 cm and 5 cm... |
3.95 to 5.85 GHz |
| F band F band The F band is the range of radio frequencies from 90 GHz to 140 GHz in the electromagnetic spectrum. This is equal to wave lengths between 2.1 mm and 3.3 mm... |
4.90 to 7.05 GHz |
| C band C band The C band is a name given to certain portions of the electromagnetic spectrum, including wavelengths of microwaves that are used for long-distance radio telecommunications. The IEEE C-band - and its slight variations - contains frequency ranges that are used for many satellite communications... |
5.85 to 8.20 GHz |
| H band H band H band can refer to two different regions of the electromagnetic spectrum, in the radio and near-infrared.-Radio:The H band is the range of radio frequencies from 6 GHz to 8 GHz in the electromagnetic spectrum. This is equal to wave lengths between 5 cm and 3.75 cm... |
7.05 to 10.10 GHz |
| X band X band The X band is a segment of the microwave radio region of the electromagnetic spectrum. In some cases, such as in communication engineering, the frequency range of X band is rather indefinitely set at approximately 7.0 to 11.2 gigahertz . In radar engineering, the frequency range is specified... |
8.2 to 12.4 GHz |
| Ku band Ku band The Kμ band is a portion of the electromagnetic spectrum in the microwave range of frequencies. This symbol refers to —in other words, the band directly below the K-band... |
12.4 to 18.0 GHz |
| K band K band K band designates certain portions of the electromagnetic spectrum, in either the microwave domain or in the infrared domain. The microwave K bands are used primarily for radar and satellite communications while the infrared K band is used for astronomical observations.-NATO K band:The NATO K band... |
15.0 to 26.5 GHz |
| Ka band Ka band The Ka band covers the frequencies of 26.5–40 GHz. The Ka band is part of the K band of the microwave band of the electromagnetic spectrum. This symbol refers to "K-above" — in other words, the band directly above the K-band... |
26.5 to 40.0 GHz |
| Q band Q band The Q band of the microwave part of the electromagnetic spectrum and ranges from 33 to 50 GHz. It sits above, and partly overlaps with, the U.S. IEEE designated Ka band . It sits below the U.S... |
33 to 50 GHz |
| U band | 40 to 60 GHz |
| V band V band The V band of the electromagnetic spectrum ranges from 50 to 75 GHz. The V band is not heavily used, except for millimeter wave radar research and other kinds of scientific research... |
50 to 75 GHz |
| W band W band The W band of the microwave part of the electromagnetic spectrum ranges from 75 to 110 GHz. It sits above the U.S. IEEE designated V band in frequency, yet overlaps the NATO designated M band... |
75 to 110 GHz |
| Y band | 325 to 500 GHz |
Broadcasting
Broadcast frequencies:- Longwave AM RadioLongwaveIn radio, longwave refers to parts of radio spectrum with relatively long wavelengths. The term is a historic one dating from the early 20th century, when the radio spectrum was considered to consist of long, medium and short wavelengths...
= 148.5 – 283.5 kHz (LF) - Mediumwave AM Radio = 530 kHz – 1710 kHz (MF)
- Shortwave AM RadioShortwave bandsShortwave bands are frequency allocations for use within the shortwave radio spectrum . They are the primary medium for applications such as maritime communications, international broadcasting and worldwide amateur radio activity because they take advantage of ionospheric skip propagation to send...
= 3 MHz – 30 MHz (HF)
Designations for television and FM radio broadcast frequencies vary between countries, see Television channel frequencies
Television channel frequencies
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 video and audio carriers. The channel itself occupies several megahertz of bandwidth....
and FM broadcast band
FM broadcast band
The FM broadcast band, used for FM broadcast radio by radio stations, differs between different parts of the world. In Europe and Africa , it spans from 87.5 to 108.0 megahertz , while in America it goes only from 88.0 to 108.0 MHz. The FM broadcast band in Japan uses 76.0 to 90 MHz...
. Since VHF and UHF frequencies are desirable for many uses in urban areas, in North America some parts of the former television broadcasting band have been reassigned to cellular phone and various land mobile communications systems. Even within the allocation still dedicated to television, TV-band device
TV-band device
TV band devices or TVBDs are new unlicensed radio frequency devices operating in the vacant channels or white spaces between US television channels in the range of 54 to 698 MHz. The rules defining these devices were announced on November 4, 2008, and published by the U.S. Federal...
s use channels without local broadcasters.
The Apex
Apex (radio band)
Apex was an experimental radio broadcasting system introduced in the United States in 1934 that used high frequencies between roughly 25 and 42 MHz and wideband AM modulation to achieve high fidelity sound with less static and distortion than medium wave AM stations in the so-called standard...
band in the United States was a pre-WWII allocation for VHF audio broadcasting; it was made obsolete after the introduction of FM broadcasting.
Air band
AirbandAirband
Airband or Aircraft band is the name for a group of frequencies in the VHF radio spectrum allocated to radio communication in civil aviation, sometimes also referred to as VHF, or phonetically as "Victor"...
refers to VHF frequencies used for navigation and voice communication with aircraft. Trans-oceanic aircraft also carry HF
HF
- Chemistry :* Hafnium, a chemical element* Hartree–Fock method, a calculation scheme in the field of computational chemistry* Hydrogen fluoride, a diatomic compound which can dissolve in water to form hydrofluoric acid, a highly corrosive solution- Computing :...
radio and satellite transceivers.
Marine band
The greatest incentive for development of radio was the need to communicate with ships out of visual range of shore. From the very early days of radio, large oceangoing vessels carried powerful long-wave and medium-wave transmitters. High-frequency allocations are still designated for ships, although satellite systems have taken over some of the safety applications previously served by 500 kHz and other frequencies. 2182 kHz2182 kHz
The radio frequency of 2182 kHz is the international calling and distress frequency for maritime radiotelephone communications on the marine MF bands.- Transmission modes :...
is a medium-wave frequency still used for marine emergency communication.
Marine VHF radio
Marine VHF radio
Marine VHF radio is installed on all large ships and most seagoing small craft. It is used for a wide variety of purposes, including summoning rescue services and communicating with harbours, locks, bridges and marinas, and operates in the VHF frequency range, between 156 to 174 MHz...
is used in coastal waters and relatively short-range communication between vessels and to shore stations. Radios are channelized, with different channels used for different purposes; marine Channel 16 is used for calling and emergencies.
Amateur radio frequencies
Amateur radio frequency allocationsAmateur radio frequency allocations
Amateur radio frequency allocation is done by national telecommunications authorities. Globally, the International Telecommunication Union oversees how much radio spectrum is set aside for amateur radio transmissions...
vary around the world. Several bands are common for amateurs world-wide, usually in the shortwave part of the spectrum. Other bands are national or regional allocations only due to differing allocations for other services, especially in the VHF and UHF parts of the radio spectrum.
Citizens' band and personal radio services
Citizens' band radioCitizens' band radio
Citizens' Band radio is, in many countries, a system of short-distance radio communications between individuals on a selection of 40 channels within the 27-MHz band. Citizens' Band is distinct from the FRS, GMRS, MURS and amateur radio...
is allocated in many countries, using channelized radios in the upper HF part of the spectrum (around 27 MHz). It used for personal, small business and hobby purposes. Other frequency allocations are used for similar services in different jurisdictions, for example UHF CB
UHF CB
UHF CB is a class-licensed citizen's band radio service authorised by the governments of Australia and New Zealand in the UHF 477 MHz band. UHF CB provides 77 channels, including 32 channels allocated to repeater stations...
is allocated in Australia. A wide range of personal radio services
Family Radio Service
The Family Radio Service is an improved walkie talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies in the ultra high frequency band. It does not suffer the interference effects found on citizens' band at 27 MHz, or the...
exist around the world, usually emphasizing short-range communication between individuals or for small businesses, simplified or no license requirements, and usually FM transceivers using around 1 watt or less.
Industrial, scientific, medical
The ISM bandISM band
The industrial, scientific and medical radio bands are radio bands reserved internationally for the use of radio frequency energy for industrial, scientific and medical purposes other than communications....
s were initially reserved for non-communications uses of RF energy, such as microwave oven
Microwave oven
A microwave oven is a kitchen appliance that heats food by dielectric heating, using microwave radiation to heat polarized molecules within the food...
s, radio-frequency heating, and similar purposes. Many unlicensed devices such as cordless telephones or wireless computer networks now use ISM frequencies, with no expectation of regulatory protection from primary ISM devices.
Land mobile bands
Bands of frequencies, especially in the VHF and UHF parts of the spectrum, are allocated for communication between fixed base stationBase station
The term base station can be used in the context of land surveying and wireless communications.- Land surveying :In the context of external land surveying, a base station is a GPS receiver at an accurately-known fixed location which is used to derive correction information for nearby portable GPS...
s and land mobile vehicle-mounted or portable
Walkie-talkie
A walkie-talkie is a hand-held, portable, two-way radio transceiver. Its development during the Second World War has been variously credited to Donald L. Hings, radio engineer Alfred J. Gross, and engineering teams at Motorola...
transceivers. In the United States these services are informally known as business band
Business band
The business band is the name used by US radio users and scanner hobbyists who listen to Federal Communications Commission licensees using Industrial/Business pool frequencies...
radio. See also Professional mobile radio
Professional Mobile Radio
Professional mobile radio are field radio communications systems which use portable, mobile, base station, and dispatch console radios...
.
Police radio
Police radio
Police radio is a communications radio system used by law enforcement agencies all over the world.Many such systems are encrypted to prevent eavesdroppers from listening in.-Portable radios:...
and other public safety services such as fire departments and ambulances are generally found in the VHF and UHF parts of the spectrum. Trunking
Trunking
In modern communications, trunking is a concept by which a communications system can provide network access to many clients by sharing a set of lines or frequencies instead of providing them individually. This is analogous to the structure of a tree with one trunk and many branches. Examples of...
systems are often used to make most efficient use of the limited number of frequencies available.
The demand for mobile telephone service has led to large blocks of radio spectrum allocated to cellular frequencies
Cellular frequencies
All cellular phone networks worldwide use a portion of the radio frequency spectrum designated as ultra high frequency, or "UHF", for the transmission and reception of their signals. The ultra high frequency band is also shared with television, Wi-Fi and Bluetooth transmission...
.
Radio control
Reliable radio controlRadio control
Radio control is the use of radio signals to remotely control a device. The term is used frequently to refer to the control of model vehicles from a hand-held radio transmitter...
uses bands dedicated to the purpose. Radio-controlled toys may use portions of unlicensed spectrum in the 27 MHz or 49 MHz bands, but more costly aircraft, boat, or land vehicle models use dedicated remote control frequencies near 72 MHz to avoid interference by unlicensed uses. Licensed amateur radio operators use portions of the 6-meter band
6-meter band
The 6-meter band is a portion of the VHF radio spectrum allocated to amateur radio use. Although located in the lower portion of the VHF band, it nonetheless occasionally displays propagation mechanisms characteristic of the HF bands. This normally occurs close to sunspot maximum, when solar...
in North America. Industrial remote control of cranes or railway locomotives use assigned frequencies that vary by area.
Radar
RadarRadar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
applications use relatively high power pulse transmitters and sensitive receivers, so radar is operated on bands not used for other purposes. Most radar bands are in the microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...
part of the spectrum, although certain important applications for meteorology
Meteorology
Meteorology is the interdisciplinary scientific study of the atmosphere. Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the 18th century. The 19th century saw breakthroughs occur after observing networks developed across several countries...
make use of powerful transmitters in the UHF band.
See also
- BandplanBandplanA bandplan or band plan is a plan for using a particular band of radio frequencies, that are a portion of the electromagnetic spectrum . Each bandplan defines the frequency range to be included, how channels are to be defined, and what will be carried on those channels...
- DXingDXingDXing is the hobby of tuning in and identifying distant radio or television signals, or making two way radio contact with distant stations in amateur radio, citizens' band radio or other two way radio communications. Many DXers also attempt to receive written verifications of reception from the...
- Frequency allocationFrequency allocationUse of radio frequency bands of the electromagnetic spectrum is regulated by governments in most countries, in a Spectrum management process known as frequency allocation or spectrum allocation. Radio propagation does not stop at national boundaries...
- Geneva Frequency Plan of 1975
- North American Radio Broadcasting AgreementNorth American Radio Broadcasting AgreementThe North American Radio Broadcasting Agreement, usually referred to as NARBA, is a treaty that took effect in March 1941 and set out the bandplan and interference rules for mediumwave AM broadcasting in North America. Although mostly replaced by other agreements in the 1980s, the basic bandplan...
- Open spectrumOpen spectrumOpen spectrum is a movement to get the Federal Communications Commission to provide more unlicensed, radio frequency spectrum that is available for use by all...
- Radio astronomyRadio astronomyRadio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of...
- Radio communication systemRadio communication systemA radio communication system sends signals by radio. Types of radio communication systems deployed depend on technology, standards, regulations, radio spectrum allocation, user requirements, service positioning, and investment....
- Scanner (radio)Scanner (radio)A scanner is a radio receiver that can automatically tune, or scan, two or more discrete frequencies, stopping when it finds a signal on one of them and then continuing to scan other frequencies when the initial transmission ceases....
- Two-way radioTwo-way radioA two-way radio is a radio that can both transmit and receive , unlike a broadcast receiver which only receives content. The term refers to a personal radio transceiver that allows the operator to have a two-way conversation with other similar radios operating on the same radio frequency...
- Ultra-widebandUltra-widebandUltra-wideband is a radio technology that can be used at very low energy levels for short-range high-bandwidth communications by using a large portion of the radio spectrum. UWB has traditional applications in non-cooperative radar imaging...
- U-NII
- WARC bandsWARC bandsThe WARC bands are three portions of the shortwave radio spectrum used by licensed amateur radio operators. They consist of 30 meters , 17 meters and 12 meters . They were named after the World Administrative Radio Conference, which in 1979 created a worldwide allocation of these bands for...
External links
- UnwantedEmissions.com A reference to radio spectrum allocations.
- "Radio spectrum: a vital resource in a wireless world" European Commission policy.