Radio waves

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Radio waves

Radio waves are electromagnetic waves

Electromagnetic radiation

Electromagnetic radiation takes the form of wave propagation waves in a vacuum or in matter. EM radiation has an electric field and magnetic field component which oscillate in phase perpendicular to each other and to the direction of energy Wave propagation....
occurring on the radio frequency

Radio frequency

Radio frequency is a frequency or rate of oscillation within the range of about 3 Hz to 300 GHz. This range corresponds to frequency of alternating current electrical signals used to produce and detect radio waves....
portion of the electromagnetic spectrum

Electromagnetic spectrum

The electromagnetic spectrum is the range of all possible electromagnetic radiation frequencies. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation from that particular object....
.
o waves were first predicted by mathematical work done in 1865 by James Clerk Maxwell

James Clerk Maxwell

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Encyclopedia

Radio waves are electromagnetic waves

Electromagnetic radiation

Radio frequency

Electromagnetic spectrum

Discovery and utilization

Atmospheric Electromagnetic Transmittance Or Opacity

Radio waves were first predicted by mathematical work done in 1865 by James Clerk Maxwell

James Clerk Maxwell

James Clerk Maxwell was a Scotland Mathematical physics. His most significant achievement was the development of the classical electromagnetic theory, synthesizing all previous unrelated observations, experiments and equations of electricity, magnetism and even optics into a consistent theory....
. Maxwell noticed wavelike properties of light and similarities in electrical and magnetic observations. He then proposed equations that described light waves and radio waves as waves of electromagnetism that travel in space. In 1887, Heinrich Hertz demonstrated the reality of Maxwell's electromagnetic waves by experimentally generating radio waves in his laboratory. Many inventions followed, making practical the use of radio waves to transfer information through space.

Nikola Tesla

Nikola Tesla

Nikola Tesla was an inventor and a mechanical engineer and electrical engineer. Tesla was born in the village of Smiljan near the town of Gospic, in Croatia ....
and Guglielmo Marconi

Guglielmo Marconi

Marchese Guglielmo Marconi was an Italy inventor, best known for his development of a radiotelegraph system, which served as the foundation for the establishment of numerous affiliated companies worldwide....
are credited with inventing systems to allow radio waves to be used for communication.

Radio portion of the electromagnetic spectrum

Radio waves are divided up into bands by frequency (and corresponding wavelength

Wavelength

In physics, wavelength is the distance between repeating units of a propagating wave of a given frequency. It is commonly designated by the Greek language letter lambda ....
) as shown in the radio frequency spectrum

Frequency spectrum

Familiar concepts associated with a frequency are colors, musical notes, radio/TV channels, and even the regular rotation of the earth. A source of light can have many colors mixed together and in different amounts ....
table below.

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 International Telecommunication Union The International Telecommunication Union is the second-oldest international organization still in existence , established to standardize and regulate international radio and telecommunications.... band	Frequency and Wavelength in air	Example uses
			< 3 Hz Hertz The hertz is a measure of frequency per unit of time, or the number of list of cycles per second. It is the SI base unit of frequency in the International System of Units , and is used worldwide in both general-purpose and scientific contexts.... > 100,000 km
Extremely low frequency Extremely low frequency Extremely low frequency is the band of radio frequencies from 3 to 30 Hertz, at one time used by the United States and Soviet Navy/Russian Navy to Communication with submarines....	ELF	1	3–30 Hz Hertz The hertz is a measure of frequency per unit of time, or the number of list of cycles per second. It is the SI base unit of frequency in the International System of Units , and is used worldwide in both general-purpose and scientific contexts.... 100,000 km – 10,000 km	Communication with submarines Communication with submarines Communication with submarines when they are submerged is a difficult technological task which requires specific techniques and devices. This is because electromagnetic radiation used in radio communication cannot travel through thick Electrical conductors such as salt water....
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 Alternating current Electric power transmission ....	SLF	2	30–300 Hz Hertz The hertz is a measure of frequency per unit of time, or the number of list of cycles per second. It is the SI base unit of frequency in the International System of Units , and is used worldwide in both general-purpose and scientific contexts.... 10,000 km – 1000 km	Communication with submarines Communication with submarines Communication with submarines when they are submerged is a difficult technological task which requires specific techniques and devices. This is because electromagnetic radiation used in radio communication cannot travel through thick Electrical conductors such as salt water....
Ultra low frequency Ultra low frequency The Ultra Low Frequency is the frequency range between 300 hertz and 3 kilohertz. Many types of waves in the ULF frequency band can be observed in the magnetosphere and on the ground....	ULF	3	300–3000 Hz Hertz The hertz is a measure of frequency per unit of time, or the number of list of cycles per second. It is the SI base unit of frequency in the International System of Units , and is used worldwide in both general-purpose and scientific contexts.... 1000 km – 100 km	Communication within mines
Very low frequency Very low frequency Very low frequency or VLF refers to radio frequency 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 are used, such as for radio navigation....	VLF	4	3–30 kHz 100 km – 10 km	Submarine communication, avalanche beacons Avalanche An avalanche is a rapid flow of snow down a slope, from either natural triggers or human activity. Typically occurring in mountainous terrain, an avalanche can mix air and water with the descending snow.... , wireless heart rate monitor Heart rate monitor A heart rate monitor is a personal training device that allows a user to measure their heart rate in real time. It usually consists of two elements: a chest strap transmitter and a wrist receiver or mobile phone .... s, geophysics Geophysics Geophysics, a major discipline of the Earth sciences, is the study of the Earth by the quantitative observation of its physical properties, especially by Seismology, Electromagnetism, Radioactive decay, galvanic and potential field methods....
Low frequency Low frequency Low Frequency or LF refers to Radio Frequency in the range of 30 kHz–300 kHz. In Europe, and parts of North Africa and of Asia, part of the LF spectrum is used for longwave service....	LF	5	30–300 kHz 10 km – 1 km	Navigation Radio navigation Radio navigation or radionavigation is the application of radio frequencies to determining a position on the Earth. Like radiolocation, it is a type of radiodetermination.... , time signals Radio clock A radio 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.... , AM longwave Longwave The longwave radio band is a range of frequencies used for AM broadcasting, which extends from 148.5 to 283.5 kHz. It falls within the low frequency part of the radio spectrum .... broadcasting
Medium frequency Medium frequency Medium frequency refers to radio frequency in the range of 300 Hertz to 3000 kHz. Part of this band is the medium wave AM broadcast band....	MF	6	300–3000 kHz 1 km – 100 m M M is the thirteenth letter of the modern Latin alphabet. Its name in English language is spelled em ....	AM (Medium-wave) broadcasts
High frequency High frequency High frequency radio frequency are between 3 and 30 Megahertz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters ....	HF	7	3–30 MHz 100 m – 10 m	Shortwave Shortwave Shortwave radio operates in the frequency range of 3,000 kHz to 30,000 kHz . In radio, short wavelength corresponds to high frequency given the inverse relationship between frequency and wavelength, thus, ?shortwave radio? is denominated so, because its wavelengths are shorter than the long wave-lengths used in early radio communications; m... broadcasts, amateur radio Amateur radio Amateur radio, often called Etymology of ham radio, is both a hobby and a service in which participants, called "hams," use various types of radio communications equipment to communicate with other radio amateurs for Public services, recreation and self-training.... and over-the-horizon aviation communications
Very high frequency Very high frequency VHF is the radio frequency range from 30 megahertz to 300 megahertz. 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 widely used telecommunication mass-media for transmitting and receiving moving , either monochrome or color, usually accompanied by sound.... broadcasts and line-of-sight ground-to-aircraft and aircraft-to-aircraft communications. Land Mobile and Maritime Mobile communications
Ultra high frequency Ultra high frequency Ultra high frequency designates a range of Electromagnetic radiation waves with frequency between 300 megahertz and 3 gigahertz . Also known as the decimetre band or decimetre wave as the wavelengths range from ten to one decimetres....	UHF	9	300–3000 MHz 1 m – 100 mm	television Television Television is a widely used telecommunication mass-media for transmitting and receiving moving , either monochrome or color, usually accompanied by sound.... broadcasts, microwave Microwave Microwaves are electromagnetic radiation with wavelengths ranging from 1 mm to 1 m, or frequency between 0.3 hertz and 300 GHz.... ovens, mobile phone Mobile phone A mobile phone is a long-range, electronic device used for mobile voice or data communication over a network of specialized base stations known as cell sites.... s, wireless LAN Wireless LAN A wireless LAN is a wireless local area network that links two or more computers or devices using Spread spectrum or OFDM modulation technology based to enable communication between devices in a limited area.... , Bluetooth Bluetooth Bluetooth is a wireless protocol for exchanging data over short distances from fixed and mobile devices, creating personal area networks . It was originally conceived as a wireless alternative to RS232 data cables.... , GPS and Two-Way Radios such as Land Mobile, FRS and GMRS Radios
Super high frequency Super high frequency Super high frequency refers to radio frequency in the range of 3 Hertz and 30 GHz. Also known as the centimeter band or centimeter wave as the wavelengths range from ten to one centimeters....	SHF	10	3–30 GHz 100 mm – 10 mm	microwave Microwave Microwaves are electromagnetic radiation with wavelengths ranging from 1 mm to 1 m, or frequency between 0.3 hertz and 300 GHz.... devices, wireless LAN Wireless LAN A wireless LAN is a wireless local area network that links two or more computers or devices using Spread spectrum or OFDM modulation technology based to enable communication between devices in a limited area.... , most modern Radar Radar Radar is a system that uses electromagnetic radiation waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain.... s
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 Radio astronomy Radio astronomy is a subfield of astronomy that studies Astronomical object at radio frequency. The initial detection of radio waves from an astronomical object was made in the 1930s, but subsequent advances have identified a number of different sources of radio emission.... , high-speed microwave radio relay Microwave radio relay Microwave radio relay is a technology for transmitting digital signal and analog signal Signalling , such as long-distance telephone calls and the relay of television programs to transmitters, between two locations on a Line-of-sight propagation radio path....
			Above 300 GHz < 1 mm

Named frequency bands

General

Broadcast Frequencies:

Longwave AM Radio = 148.5 - 283.5 kHz (LF)
Mediumwave AM Radio = 530 kHz - 1710 kHz (MF)
Shortwave AM Radio = 3 MHz - 30 MHz (HF)
TV Band I (Channels 2 - 6) = 54 MHz - 88 MHz (VHF)
FM Radio Band II = 88 MHz - 108 MHz (VHF)
TV Band III (Channels 7 - 13) = 174 MHz - 216 MHz (VHF)
TV Bands IV & V (Channels 14 - 69) = 470 MHz - 806 MHz (UHF)

For more information see the NTIA frequency allocation chart: http://www.ntia.doc.gov/osmhome/allochrt.html

Amateur radio frequencies

The range of allowed amateur radio

Amateur radio

Amateur radio, often called Etymology of ham radio, is both a hobby and a service in which participants, called "hams," use various types of radio communications equipment to communicate with other radio amateurs for Public services, recreation and self-training....
frequencies vary between countries. The article Amateur radio frequency allocations

Amateur 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....
lists frequencies allocated for amateur radio use.

IEEE US

Per IEEE Std 521-2002. Reaffirmed standard of 1984; originally dates back to WWII.

Band	Frequency range	Origin of name
HF band High frequency High frequency radio frequency are between 3 and 30 Megahertz. Also known as the decameter band or decameter wave as the wavelengths range from one to ten decameters ....	3 to 30 MHz	High Frequency
VHF band	30 to 300 MHz	Very High Frequency
UHF band	300 to 1000 MHz	Ultra High Frequency Frequencies from 216 to 450 MHz were sometimes called P-band: Previous, since early British United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom , the UK or Britain,is a sovereign state located off the northwestern coast of continental Europe.... radar Radar Radar is a system that uses electromagnetic radiation waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain.... used this band but later switched to higher frequencies.
L band L band L Band is used to refer to three different bands of the electromagnetic spectrum....	1 to 2 GHz	Long wave
S band S band The S band ranges from 2 to 4 GHz, crossing the boundary between Ultra high frequency and Super high frequency 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 C band is a name given to certain portions of the electromagnetic spectrum, as well as a range of wavelengths of light, used for communications....	4 to 8 GHz	Compromise between S and X
X band X band The X band is part of the microwave region of the electromagnetic spectrum. Its frequency range is from 7 to 12.5 GHz. The 10.7-12.5 GHz portion overlaps the Ku band....	8 to 12 GHz	Used in WW II World War II World War II, or the Second World War , was a global military conflict which involved a Participants in World War II, including all of the great powers, organised into two opposing military alliances: the Allies of World War II and the Axis powers.... for fire control Fire-control system A fire-control system is a computer, often mechanical, 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 accurately.... , X for cross (as in crosshair Crosshair A crosshair or reticle is a shape superimposed on an image that is used for precise alignment of a device, most notably that of a scope rifle.... )
K_u band Ku band The Ku band is a portion of the electromagnetic spectrum in the microwave range of frequencies. This symbol refers to "K-under" ?in other words, the band directly below the K-band....	12 to 18 GHz	Kurz-under
K band K band NATO K bandThe NATO K band is defined as a frequency band between 20 and 40 GHz ....	18 to 27 GHz	German German language German is a West Germanic languages, thus related to and classified alongside English language and Dutch language. It is one of the world's world language and the most widely spoken mother tongue in the European Union.... Kurz (short)
K_a band Ka band The Ka band covers the frequencies of 26.5-40GHz. The Ka band is part of the K band of the microwave band of the electromagnetic spectrum....	27 to 40 GHz	Kurz-above
V band V band The V band of the electromagnetic spectrum ranges from 40 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 111 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 standardized set of letter basic written symbols each of which roughly represents a phoneme, a spoken language, either as it exists now or as it was in the past....
mm band	110 to 300 GHz

EU, NATO
NATO

The North Atlantic Treaty Organization , also called the Atlantic Alliance, is a military alliance established by the signing of the North Atlantic Treaty on 4 April 1949....
, 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 frequency from 250 Hertz to 500 MHz in the electromagnetic spectrum. This is equal to wave lengths between 1.2 m and 0.6 m....	0.25 to 0.5 GHz
C band C band C band is a name given to certain portions of the electromagnetic spectrum, as well as a range of wavelengths of light, used for communications....	0.5 to 1.0 GHz
D band D band D band is the range of radio frequency from 1 Hertz to 2 GHz in the electromagnetic spectrum. This is equal to wave lengths between 30 cm and 15 cm....	1 to 2 GHz
E band E band The NATO E band is the range of radio frequency from 2 Hertz to 3 GHz in the electromagnetic spectrum. This is equal to wave lengths between 15 cm and 10 cm....	2 to 3 GHz
F band F band The F band is the range of radio frequency from 3 Hertz to 4 GHz in the electromagnetic spectrum. This is equal to wave lengths between 10 cm and 7.5 cm....	3 to 4 GHz
G band G band NATO G bandThe G band in the modern sense is the range of radio frequency from 4 Hertz to 6 GHz in the electromagnetic spectrum....	4 to 6 GHz
H band H band The H band is the range of radio frequency from 6 Hertz 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 frequency from 8 Hertz to 10 GHz in the electromagnetic spectrum. This is equal to wave lengths between 3.75 cm and 3 cm....	8 to 10 GHz
J band J band The J band is the range of radio frequency from 10 Hertz to 20 GHz in the electromagnetic spectrum. This is equal to wave lengths between 3 cm and 1.5 cm....	10 to 20 GHz
K band K band NATO K bandThe NATO K band is defined as a frequency band between 20 and 40 GHz ....	20 to 40 GHz
L band L band L Band is used to refer to three different bands of the electromagnetic spectrum....	40 to 60 GHz
M band M band The M band is the range of radio frequency from 60 Hertz to 100 GHz in the electromagnetic spectrum. This is equal to wave lengths between 5 mm and 3 mm....	60 to 100 GHz

Waveguide
Waveguide

A waveguide is a structure which guides waves, such as electromagnetic waves or sound waves. There are different types of waveguide for each type of wave....
frequency bands

Band	Frequency range
R band	1.70 to 2.60 GHz
D band D band D band is the range of radio frequency from 1 Hertz to 2 GHz in the electromagnetic spectrum. This is equal to wave lengths between 30 cm and 15 cm....	2.20 to 3.30 GHz
S band S band The S band ranges from 2 to 4 GHz, crossing the boundary between Ultra high frequency and Super high frequency 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 frequency from 2 Hertz to 3 GHz in the electromagnetic spectrum. This is equal to wave lengths between 15 cm and 10 cm....	3.30 to 4.90 GHz
G band G band NATO G bandThe G band in the modern sense is the range of radio frequency from 4 Hertz to 6 GHz in the electromagnetic spectrum....	3.95 to 5.85 GHz
F band F band The F band is the range of radio frequency from 3 Hertz to 4 GHz in the electromagnetic spectrum. This is equal to wave lengths between 10 cm and 7.5 cm....	4.90 to 7.05 GHz
C band C band C band is a name given to certain portions of the electromagnetic spectrum, as well as a range of wavelengths of light, used for communications....	5.85 to 8.20 GHz
H band H band The H band is the range of radio frequency from 6 Hertz 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 part of the microwave region of the electromagnetic spectrum. Its frequency range is from 7 to 12.5 GHz. The 10.7-12.5 GHz portion overlaps the Ku band....	8.2 to 12.4 GHz
Ku band Ku band The Ku band is a portion of the electromagnetic spectrum in the microwave range of frequencies. This symbol refers to "K-under" ?in other words, the band directly below the K-band....	12.4 to 18.0 GHz
K band K band NATO K bandThe NATO K band is defined as a frequency band between 20 and 40 GHz ....	15.0 to 26.5 GHz
Ka band Ka band The Ka band covers the frequencies of 26.5-40GHz. The Ka band is part of the K band of the microwave band of the electromagnetic spectrum....	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....	33 to 50 GHz
U band	40 to 60 GHz
V band V band The V band of the electromagnetic spectrum ranges from 40 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 111 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

Radio waves

Discovery and utilization

Radio portion of the electromagnetic spectrum

Named frequency bands

General

Amateur radio frequencies

IEEE US

EU, NATONATOThe North Atlantic Treaty Organization , also called the Atlantic Alliance, is a military alliance established by the signing of the North Atlantic Treaty on 4 April 1949...., US ECM frequency designations

WaveguideWaveguideA waveguide is a structure which guides waves, such as electromagnetic waves or sound waves. There are different types of waveguide for each type of wave.... frequency bands

See also

EU, NATO
NATO

The North Atlantic Treaty Organization , also called the Atlantic Alliance, is a military alliance established by the signing of the North Atlantic Treaty on 4 April 1949....
, US ECM frequency designations

Waveguide
Waveguide

A waveguide is a structure which guides waves, such as electromagnetic waves or sound waves. There are different types of waveguide for each type of wave....
frequency bands