radio frequency

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Related to Radio-frequency: Radio-frequency ablation

See also: Radio Frequencies (table)Radio Frequencies
Frequency
(kHz)
Name Abbr.
10–30 Very low VLF
30–300 Low LF
300–3,000 Medium MF
3,000–30,000 High HF
30,000–300,000 Very high VHF
300,000–3,000,000 Ultra high UHF
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radio frequency,

range of electromagnetic waves with a frequency or wavelength suitable for communication uses. Some of these waves serve as carriers of the lower-frequency audio waves; others are modulated by video or digital information. Short waves have relatively high frequencies; long waves have relatively low frequencies. Radio waves are identified by their frequencies, expressed in kilohertz (kHz), i.e., thousands of cycles per second, in megahertz (MHz), i.e., millions of cycles per second, or in gigahertz (GHz), i.e., billions of cycles per seconds. A range, or band, of radio frequencies is assigned to a broadcasting service by the nation in which it operates. In the United States, the Federal Communications CommissionFederal Communications Commission
(FCC), independent executive agency of the U.S. government established in 1934 to regulate interstate and foreign communications in the public interest.
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 is responsible for that task. Signals in the amplitude modulation (AM) broadcast band in the Americas have frequencies ranging from 530 to 1,700 kHz. Frequency modulation (FM) broadcast frequencies in most countries range from approximately 88 MHz to 108 MHz. Other frequencies are assigned to amateur (ham) radio, citizen band (CB) radio, television broadcasting, cellular telephones, global positioning systems, and other uses. Countries cooperate on on a worldwide basis through the International Telecommunication UnionInternational Telecommunication Union
(ITU), specialized agency of the United Nations, with headquarters at Geneva. It was created in 1934 as a result of the merging of the International Telegraph Union (est.
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, which holds periodic conferences. See also the table entitled Radio FrequenciesRadio Frequencies
Frequency
(kHz)
Name Abbr.
10–30 Very low VLF
30–300 Low LF
300–3,000 Medium MF
3,000–30,000 High HF
30,000–300,000 Very high VHF
300,000–3,000,000 Ultra high UHF
..... Click the link for more information.
 for the classification of radio frequencies.
The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/

radio frequency

See radio waves.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006

radio frequency

[′rād·ē·ō ‚frē·kwən·sē]
(electromagnetism)
A frequency at which coherent electromagnetic radiation of energy is useful for communication purposes; roughly the range from 10 kilohertz to 100 gigahertz. Abbreviated rf.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

RF

(Radio Frequency) The range of electromagnetic frequencies above the audio range and below infrared light (from 10 kHz to 300 GHz). RF transmission includes AM and FM radio, analog and digital TV, satellite communications, cordless phones, cellular and Wi-Fi. Signals can be focused in one direction (directional), or they can transmit in all directions (omnidirectional).

Frequency and Power
The range of frequencies and power output determine how well RF signals can penetrate objects. Signals up to 5 GHz can generally transmit through wooden and plaster walls in their path, but the higher the frequency, the more an unobstructed view from transmitter to receiver is required. See line of sight, RF modulation, RF shielding, RF remote control, RFI, microwave and ISM band.


RF Ports
Radio frequency ports (right) are typically coaxial cable connectors for antennas and TVs. See coaxial cable.
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References in periodicals archive ?
An expression for the evolution operator in a radio-frequency coil may be found in Ref.
RADIO-FREQUENCY IDENTIFICATION, commonly known as RFID, is the technology behind highway toll passes and a host of other applications ranging from livestock identification to library book tracking.
Now that semiconductors have become so small, they can be used in high-performance radio-frequency communication systems and devices.
Generally, the continuous waves of conventional radio-frequency transmissions encounter interference from stray signals reflecting off of the walls and objects inside a house or office.
When the researchers blast a short pulse of radio-frequency energy along this catheter, a small, targeted region of the heart tissue -- including the aberrant loop -- heats up and dies.
Martin introduces alternatives to ordinary transmission lines for the design and implementation of radio-frequency and microwaves device components with increased degrees of freedom, more possibilities for reducing device size, improved performance, or the ability to achieve novel functions.
To control ion energies, radio-frequency (rf) power is applied to the substrate electrode, but the effect of the rf power on ion energies is quite complicated.
What is described as the first radio-frequency welding system for plastics based on a 500-watt generator rather than the conventional 2 kw is being introduced this month by Sebra of Tucson, Ariz.
The developers of the receivers expect them to weed out signals from natural sources (such as pulsars), artificial ones produced on Earth (radio-frequency interference, hoaxes) and any other "false alarms" that filters or computer algorithms can remove.
Performance Optimization Techniques in Analog, Mixed-Signal, and Radio-Frequency Circuit Design

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