346:
50:
1205:. So radio waves directed at an angle into the sky can return to Earth beyond the horizon; this is called "skip" or "skywave" propagation. By using multiple skips communication at intercontinental distances can be achieved. Skywave propagation is variable and dependent on atmospheric conditions; it is most reliable at night and in the winter. Widely used during the first half of the 20th century, due to its unreliability skywave communication has mostly been abandoned. Remaining uses are by military
2948:
1490:
1060:: This refers to radio waves that travel in a straight line from the transmitting antenna to the receiving antenna. It does not necessarily require a cleared sight path; at lower frequencies radio waves can pass through buildings, foliage and other obstructions. This is the only method of propagation possible at frequencies above 30 MHz. On the surface of the Earth, line of sight propagation is limited by the visual
866:
3888:
831:. A photon can have one of two possible values of spin; it can spin in a right-hand sense about its direction of motion, or in a left-hand sense. Right circularly polarized radio waves consist of photons spinning in a right hand sense. Left circularly polarized radio waves consist of photons spinning in a left hand sense. Plane polarized radio waves consist of photons in a
2496:
243:
1112:. Diffraction causes radio waves to bend around obstructions such as a building edge, a vehicle, or a turn in a hall. Radio waves also partially reflect from surfaces such as walls, floors, ceilings, vehicles and the ground. These propagation methods occur in short range radio communication systems such as
811:
consists of two collinear metal rods. If the rods are horizontal, it radiates horizontally polarized radio waves, while if the rods are vertical, it radiates vertically polarized waves. An antenna receiving the radio waves must have the same polarization as the transmitting antenna, or it will suffer
1470:
However, unlike infrared waves, which are mainly absorbed at the surface of objects and cause surface heating, radio waves are able to penetrate the surface and deposit their energy inside materials and biological tissues. The depth to which radio waves penetrate decreases with their frequency, and
1508:
Since the heating effect is in principle no different from other sources of heat, most research into possible health hazards of exposure to radio waves has focused on "nonthermal" effects; whether radio waves have any effect on tissues besides that caused by heating. Radiofrequency electromagnetic
1569:
zone of the radiation pattern. In closer proximity to the transmitter, i.e., in the "near field" zone, the physical relationships between the electric and magnetic components of the field can be complex, and it is best to use the field strength units discussed above. Power density is measured in
1398:
at which it oscillates. The resonant frequency is set equal to the frequency of the desired radio station. The oscillating radio signal from the desired station causes the tuned circuit to oscillate in sympathy, and it passes the signal on to the rest of the receiver. Radio signals at other
1321:
At the receiver, the oscillating electric and magnetic fields of the incoming radio wave push the electrons in the receiving antenna back and forth, creating a tiny oscillating voltage which is a weaker replica of the current in the transmitting antenna. This voltage is applied to the
1570:
terms of power per unit area, for example, with the unit milliwatt per square centimeter (mW/cm). When speaking of frequencies in the microwave range and higher, power density is usually used to express intensity since exposures that might occur would likely be in the far field zone.
1620:
1168:
which follow the contour of the Earth. This makes it possible for mediumwave and longwave broadcasting stations to have coverage areas beyond the horizon, out to hundreds of miles. As the frequency drops, the losses decrease and the achievable range increases. Military
1361:
The radio waves from many transmitters pass through the air simultaneously without interfering with each other. They can be separated in the receiver because each transmitter's radio waves oscillate at a different rate, in other words each transmitter has a different
1221:
frequencies, atmospheric gases begin absorbing radio waves, so the range of practical radio communication systems decreases with increasing frequency. Below about 20 GHz atmospheric attenuation is mainly due to water vapor. Above 20 GHz, in the
3876:
471:. In an antenna transmitting radio waves, the electrons in the antenna emit the energy in discrete packets called radio photons, while in a receiving antenna the electrons absorb the energy as radio photons. An antenna is a
1485:
of the material, which is the depth within which 63% of the energy is deposited. For example, the 2.45 GHz radio waves (microwaves) in a microwave oven penetrate most foods approximately 2.5 to 3.8 cm.
1972:
723:
1027:, how radio waves move in free space and over the surface of the Earth, is vitally important in the design of practical radio systems. Radio waves passing through different environments experience
1542:
Since radio frequency radiation has both an electric and a magnetic component, it is often convenient to express intensity of radiation field in terms of units specific to each component. The unit
1829:
667:
305:
demonstrated the reality of
Maxwell's electromagnetic waves by experimentally generating radio waves in his laboratory, showing that they exhibited the same wave properties as light:
1248:
systems, information is transported across space using radio waves. At the sending end, the information to be sent, in the form of a time-varying electrical signal, is applied to a
1513:(IARC) as having "limited evidence" for its effects on humans and animals. There is weak mechanistic evidence of cancer risk via personal exposure to RF-EMF from mobile telephones.
1020:, longer wavelengths can bend around obstructions, and unlike other electromagnetic waves they tend to be scattered rather than absorbed by objects larger than their wavelength.
1501:
of a working radio transmitter, can cause damage to the lens of the eye by heating. A strong enough beam of radio waves can penetrate the eye and heat the lens enough to cause
454:. When radio waves strike the receiving antenna they push the electrons in the metal back and forth, creating tiny oscillating currents which are detected by the receiver.
2893:
2476:
2454:
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perpendicular to the direction of motion. A plane-polarized radio wave has an electric field that oscillates in a plane perpendicular to the direction of motion. In a
598:
1177:(ELF) communication systems can communicate over most of the Earth. VLF and ELF radio waves can also penetrate water to hundreds of meters deep, so they are used to
513:
2301:
2229:
2191:
1788:
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2015:
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applies oscillating electric current to the antenna, and the antenna radiates the power as radio waves. Radio waves are received by another antenna attached to a
1938:
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is divided into a number of radio bands on the basis of frequency, allocated to different uses. Higher-frequency, shorter-wavelength radio waves are called
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2408:
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1510:
395:) and current in the rods. The oscillating currents (black arrows) flow down the transmission line and through the receiver (represented by the resistance
1565:. Power density is most accurately used when the point of measurement is far enough away from the RF emitter to be located in what is referred to as the
835:
of right and left hand spin states. The electric field consists of a superposition of right and left rotating fields, resulting in a plane oscillation.
215:
between different users, the artificial generation and use of radio waves is strictly regulated by law, coordinated by an international body called the
2075:
188:
and many other applications. Different frequencies of radio waves have different propagation characteristics in the Earth's atmosphere; long waves can
2412:
1226:
band, other atmospheric gases begin to absorb the waves, limiting practical transmission distances to a kilometer or less. Above 300 GHz, in the
2642:
1051:
more useful for specific purposes than others. Practical radio systems mainly use three different techniques of radio propagation to communicate:
748:, the distance that a radio wave travels in vacuum in one second, is 299,792,458 meters (983,571,056 ft), which is the wavelength of a 1
1604:
1408:
995:
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for deep heating of body tissue, to promote increased blood flow and healing. More recently they have been used to create higher temperatures in
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An antenna emits polarized radio waves, with the polarization determined by the direction of the metal antenna elements. For example, a
2374:
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the carrier, altering some aspect of it, encoding the information on the carrier. The modulated carrier is amplified and applied to an
519:. So the antenna of even a very low power transmitter emits an enormous number of photons every second. Therefore, except for certain
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1966:
1614:
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1932:
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262:(small dark vertical line in the center). The E and H fields are perpendicular, as implied by the phase diagram in the lower right.
816:
from warm objects, emit unpolarized waves, consisting of incoherent short wave trains in an equal mixture of polarization states.
3788:
1318:, which radiate the energy away from the antenna as radio waves. The radio waves carry the information to the receiver location.
1016:. Radio waves have the ability to pass through the atmosphere in any weather, foliage, and through most building materials. By
678:
1520:. A metal screen shields against radio waves as well as a solid sheet as long as the holes in the screen are smaller than about
2259:
1135:
567:
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2009:
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1047:. Different frequencies experience different combinations of these phenomena in the Earth's atmosphere, making certain
461:, like other electromagnetic radiation such as light, radio waves can alternatively be regarded as streams of uncharged
212:
49:
43:
1516:
Radio waves can be shielded against by a conductive metal sheet or screen, an enclosure of sheet or screen is called a
3610:
2994:
2833:
1915:
1671:
1008:
Radio waves are more widely used for communication than other electromagnetic waves mainly because of their desirable
988:
789:
301:". Maxwell proposed that light consisted of electromagnetic waves of very short wavelength. In 1887, German physicist
35:
1330:
to separate the desired radio station's radio signal from all the other radio signals picked up by the antenna, then
600:
is the distance from one peak (crest) of the wave's electric field to the next, and is inversely proportional to the
1956:
121:
inch), about the diameter of a grain of rice. Like all electromagnetic waves, radio waves in a vacuum travel at the
3842:
3697:
3670:
2989:
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because it creates the radio waves that "carry" the information through the air. The information signal is used to
793:
629:
528:
278:
345:
164:, which processes the received signal. Radio waves are very widely used in modern technology for fixed and mobile
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92:
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574:. Air is tenuous enough that in the Earth's atmosphere radio waves travel at very nearly the speed of light.
1813:
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3339:
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2083:
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1073:
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1134:, in which radio waves travel from the transmitting to the receiving antenna via multiple paths. The waves
3846:
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3431:
1584:
1415:
1206:
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532:
326:
286:
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Electric waves: being researches on the propagation of electric action with finite velocity through space
3850:
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1551:
1281:
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1085:
832:
785:
781:
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in space such as the Sun, galaxies and nebulas. All warm objects radiate high frequency radio waves (
325:
developed the first practical radio transmitters and receivers around 1894–1895. He received the 1909
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of the wave. The relation of frequency and wavelength in a radio wave traveling in vacuum or air is
484:
428:
318:
298:
220:
1737:
1230:, virtually all the power is absorbed within a few meters, so the atmosphere is effectively opaque.
329:
for his radio work. Radio communication began to be used commercially around 1900. The modern term "
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3702:
3615:
3334:
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3304:
3284:
3035:
2773:
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cooks food. Radio waves have been applied to the body for 100 years in the medical therapy of
1334:
the signal so it is stronger, then finally extracts the information-bearing modulation signal in a
1285:
1245:
912:
813:
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emitting microwave photons, radio wave emission and absorption is usually regarded as a continuous
472:
462:
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165:
146:
69:
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820:
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antenna receiving a radio wave. The antenna consists of two metal rods connected to a receiver
3712:
3590:
3527:
3492:
3180:
3176:
3157:
3153:
3149:
2590:
2580:
2579:. Developments in electromagnetic theory and applications series. Dordrecht: Kluwer Academic.
2558:
2486:
2444:
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2213:
2181:
2175:
2154:
2043:
2005:
1962:
1928:
1819:
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1610:
1443:. The main effect of absorption of radio waves by materials is to heat them, similarly to the
1249:
1164:
radio waves can bend over hills and mountains, and propagate beyond the horizon, traveling as
1088:
links transmit telephone and television signals over long distances up to the visual horizon.
1024:
1009:
844:
800:
is perpendicular to the electric field, and the electric and magnetic field are oriented in a
788:
wave the electric field at any point rotates about the direction of travel, once per cycle. A
757:
583:
458:
447:
322:
65:
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2037:
489:
3717:
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3060:
2928:
2743:
2524:
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1997:
1554:, and these units are used to provide information about the levels of electric and magnetic
1125:
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a severe loss of reception. Many natural sources of radio waves, such as the sun, stars and
435:
404:
350:
272:
255:
185:
177:
134:
126:
84:; these are the radio waves. In this animation the action is shown slowed down tremendously.
54:
2947:
1489:
3829:
3814:
3630:
3542:
3532:
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2323:"IARC Classifies Radiofrequency Electromagnetic Fields as Possibly Carcinogenic to Humans"
1579:
1379:
1327:
1303:
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1223:
1069:
886:
801:
443:
259:
157:
77:
73:
57:
39:
31:
2440:
Electromagnetic
Compatibility in Medical Equipment: A Guide for Designers and Installers
125:, and in the Earth's atmosphere at a slightly lower speed. Radio waves are generated by
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3635:
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3547:
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161:
122:
81:
61:
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3256:
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3141:
3075:
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2728:
2536:
2287:
Radio-Frequency and ELF Electromagnetic
Energies: A handbook for health professionals
1436:
1383:
1210:
1121:
938:
385:
306:
1350:
to produce a visible image, or other devices. A digital data signal is applied to a
566:. When passing through a material medium, they are slowed depending on the medium's
3880:
3732:
3692:
3557:
3195:
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1517:
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969:
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571:
408:
169:
130:
2111:
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3474:
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3045:
3027:
2923:
2290:. Industrial Health and Safety Series. John Wiley & Sons. pp. 177–179.
2215:
Build Your Own Low-power
Transmitters: Projects for the Electronics Experimenter
1641:
1472:
1391:
1339:
1335:
1190:
1153:
1148:
1104:
1040:
1017:
964:
959:
917:
515:, the energy of individual radio photons is extremely small, from 10 to 10
412:
314:
193:
189:
160:, which radiates the waves. They are received by another antenna connected to a
153:
204:), while much shorter wavelengths bend or diffract very little and travel on a
3522:
3349:
3017:
3012:
2966:
2572:
1531:
1481:
1440:
1432:
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1048:
1032:
1013:
907:
578:
381:
310:
236:
197:
100:
2609:
1561:
Another commonly used unit for characterizing an RF electromagnetic field is
1197:
wavelengths, radio waves reflect off conductive layers of charged particles (
3809:
3682:
3517:
3464:
3454:
3415:
3358:
3205:
2981:
2959:
2938:
2913:
2594:
1914:"Ch. 1: Terminology and technical characteristics – Terms and definitions".
1670:"Ch. 1: Terminology and technical characteristics - Terms and definitions".
1566:
1498:
1460:
1387:
1375:
1371:
1367:
1363:
1331:
1218:
1194:
865:
753:
601:
424:
416:
224:
138:
108:
96:
64:
lines. The antenna in the center is two vertical metal rods connected to a
2871:
2528:
17:
2039:
Principles of
Terahertz Time-Domain Spectroscopy: An Introductory Textbook
792:
wave rotates in a right-hand sense about the direction of travel, while a
3459:
3444:
3373:
3190:
3168:
3163:
3133:
2933:
1502:
1444:
1428:
1420:
1351:
1343:
1307:
1277:
1213:, and by shortwave broadcasting stations to broadcast to other countries.
1157:
780:
radio wave the electric field oscillates in a horizontal direction. In a
480:
439:
369:
242:
152:
Radio waves are generated artificially by an electronic device called a
3737:
3242:
3228:
2620:
1185:
1061:
922:
442:
flowing back and forth in a specially shaped metal conductor called an
201:
80:(−). Loops of electric field leave the antenna and travel away at the
30:
This article is about the radiation. For the generic oscillation, see
3266:
3261:
3251:
3223:
3218:
3213:
3184:
3113:
2398:"Radiofrequency Electromagnetic Fields: Evaluation of cancer hazards"
1455:
to vibrate back and forth, increasing the temperature; this is how a
1139:
824:
768:
Like other electromagnetic waves, a radio wave has a property called
467:
192:
around obstacles like mountains and follow the contour of the Earth (
2174:
van der Vorst, André; Rosen, Arye; Kotsuka, Youji (2006).
208:, so their propagation distances are limited to the visual horizon.
2396:
Baan, R.; Grosse, Y.; Lauby-Secretan, B.; El
Ghissassi, F. (2014).
1850:
1326:, which extracts the information signal. The receiver first uses a
3562:
3449:
3108:
3004:
2918:
1488:
1239:
1077:
880:
857:
524:
516:
476:
344:
241:
173:
48:
2036:
Coutaz, Jean-Louis; Garet, Frederic; Wallace, Vincent P. (2018).
1497:
Looking into a source of radio waves at close range, such as the
784:
wave the electric field oscillates in a vertical direction. In a
3103:
3098:
2613:
1451:
or wood fire. The oscillating electric field of the wave causes
1424:
1399:
frequencies are blocked by the tuned circuit and not passed on.
1198:
3388:
2875:
2624:
3123:
1642:"Radio wave | Examples, Uses, Facts, & Range | Britannica"
1550:(A/m) is used for the magnetic component. One can speak of an
772:, which is defined as the direction of the wave's oscillating
228:
1064:
to about 64 km (40 mi). This is the method used by
281:
that was proposed in 1867 by
Scottish mathematical physicist
2946:
1102:: Radio waves can reach points beyond the line-of-sight by
718:{\displaystyle c\approx 2.9979\times 10^{8}{\text{ m/s}}~.}
419:
and other natural processes in the Earth's atmosphere, and
2517:
1419:, which means they do not have enough energy to separate
1715:. Cambridge, UK: Cambridge University Press. p. 6.
2513:"VIII. A Dynamical Theory of the Electromagnetic Field"
1740:. American Association for the Advancement of Science.
1546:(V/m) is used for the electric component, and the unit
434:
Radio waves are produced artificially by time-varying
3864:
760:) has a wavelength of 299.79 meters (983.6 ft).
734:
681:
632:
609:
586:
552:
492:
368:) of the incoming wave results in oscillation of the
231:, propagated in space without artificial guide". The
2284:
Hitchcock, R. Timothy; Patterson, Robert M. (1995).
1310:
in the antenna back and forth, creating oscillating
372:
in the rods, charging the ends alternately positive
3802:
3766:
3653:
3483:
3430:
3423:
3348:
3275:
3204:
3132:
3084:
3026:
3003:
2980:
819:The polarization of radio waves is determined by a
2142:
1851:"Electromagnetic Frequency, Wavelength and Energy
740:
717:
661:
615:
592:
558:
507:
380:. Since the length of the antenna is one half the
277:Radio waves were first predicted by the theory of
137:. Naturally occurring radio waves are emitted by
111:(GHz) and wavelengths greater than 1 millimeter (
2177:RF/Microwave Interaction with Biological Tissues
2105:
2103:
2101:
1815:Our Changing Views of Photons: A Tutorial Memoir
1152:: At lower frequencies below 2 MHz, in the
1084:to transmit beams of microwaves, point-to-point
796:wave rotates in the opposite sense. The wave's
2256:Biological Effects of Radiofrequency Radiation
1961:. Cambridge University Press. pp. 16–17.
1738:"Heinrich Hertz and electromagnetic radiation"
1609:. Cambridge University Press. pp. 16–17.
3400:
2887:
2636:
2475:National Association of Broadcasters (1996).
1713:The natural philosophy of James Clerk Maxwell
1096:and spacecraft billions of miles from Earth.
989:
662:{\displaystyle \lambda ={\frac {\;c\;}{f}}~,}
8:
2250:Elder, Joe Allen; Cahill, Daniel F. (1984).
1447:waves radiated by sources of heat such as a
804:with respect to the direction of radiation.
72:to the rods, which charges them alternately
38:. For the British broadcasting station, see
2180:. John Wiley & Sons. pp. 121–122.
1511:International Agency for Research on Cancer
384:of the wave, the oscillating field induces
3427:
3407:
3393:
3385:
2963:
2894:
2880:
2872:
2661:
2643:
2629:
2621:
2553:. Cornell University Library. Ithaca, NY:
2363:"Agents Classified by the IARC Monographs"
2145:RF and Microwave Radiation Safety Handbook
1991:
1989:
996:
982:
848:
646:
642:
411:. Natural sources of radio waves include
2437:Kimmel, William D.; Gerke, Daryl (2018).
2212:Graf, Rudolf F.; Sheets, William (2001).
1763:
1761:
1759:
1201:) in a part of the atmosphere called the
733:
704:
698:
680:
639:
631:
608:
585:
551:
491:
1479:; it is given by a parameter called the
1382:in the receiver consists of one or more
200:and return to Earth beyond the horizon (
68:(not shown). The transmitter applies an
3871:
2478:Antenna & Tower Regulation Handbook
1818:. Oxford University Press. p. 54.
1595:
1409:Medical applications of radio frequency
1209:systems, by some automated systems, by
951:
930:
899:
872:
856:
107:, typically with frequencies below 300
3748:Wireless electronic devices and health
2004:. John Wiley and Sons. pp. 3–10.
1012:properties, stemming from their large
285:. His mathematical theory, now called
2481:. Science and Technology Department.
2377:from the original on 6 September 2019
2076:"Studying the Energy of the Universe"
1925:International Telecommunication Union
1358:, which interacts with a human user.
1306:. The oscillating current pushes the
1179:communicate with submerged submarines
219:(ITU), which defines radio waves as "
217:International Telecommunication Union
196:), shorter waves can reflect off the
7:
3774:List of civilian radiation accidents
3743:Wireless device radiation and health
3738:Biological dose units and quantities
3688:Electromagnetic radiation and health
2252:"Biological Effects of RF Radiation"
1403:Biological and environmental effects
1338:. The recovered signal is sent to a
543:Radio waves in vacuum travel at the
2122:from the original on 2 October 2009
1509:fields have been classified by the
1394:. The tuned circuit has a natural
60:radiating radio waves, showing the
3723:Radioactivity in the life sciences
2577:Wave Propagation in the Ionosphere
1346:to produce sound, or a television
1268:representing moving images from a
297:could travel through space as an "
25:
2149:(2nd ed.). Newnes. pp.
1744:from the original on 15 June 2022
27:Type of electromagnetic radiation
3886:
3874:
2855:
2499:from the original on 1 May 2018.
1944:from the original on 2017-08-29.
1865:from the original on 9 June 2019
1700:from the original on 2017-08-29.
1439:, causing chemical reactions or
864:
446:. An electronic device called a
254:(H) of radio waves emitted by a
2612:. Science Mission Directorate.
2457:from the original on 2024-09-22
2418:from the original on 2018-12-10
2343:from the original on 2018-12-12
2304:from the original on 2024-09-22
2266:from the original on 2024-09-22
2232:from the original on 2024-09-22
2194:from the original on 2024-09-22
2056:from the original on 2023-02-21
2018:from the original on 2024-09-22
1975:from the original on 2024-09-22
1832:from the original on 2024-09-22
1794:from the original on 2021-10-28
1652:from the original on 2024-09-13
1623:from the original on 2024-09-22
1471:also depends on the material's
479:, so the radio photons are all
2082:. NASA website. Archived from
2002:Introduction to RF Propagation
1885:"How Radio Waves Are Produced"
1771:Radio Antennas and Propagation
1711:Harman, Peter Michael (1998).
1252:. The information, called the
333:" replaced the original name "
1:
1955:Ellingson, Steven W. (2016).
1603:Ellingson, Steven W. (2016).
1142:and other reception problems.
1128:. A drawback of this mode is
523:processes such as atoms in a
521:molecular electron transition
227:arbitrarily lower than 3,000
149:emitted by all warm objects.
1207:over-the-horizon (OTH) radar
403:Radio waves are radiated by
70:alternating electric current
3611:Cosmic background radiation
2995:Ultra-high-energy gamma ray
2443:. Routledge. p. 6.67.
1558:at a measurement location.
1467:and to kill cancer cells.
839:Propagation characteristics
475:emitter of photons, like a
289:, predicted that a coupled
156:, which is connected to an
36:Radio frequency engineering
34:. For the electronics, see
3925:
3840:
3698:Lasers and aviation safety
2990:Very-high-energy gamma ray
1998:"1.2 Modes of Propagation"
1777:. Newnes. pp. 2, 12.
1406:
1260:representing sound from a
1237:
1160:bands, due to diffraction
842:
790:right circularly polarized
421:astronomical radio sources
270:
267:Discovery and exploitation
186:wireless computer networks
29:
3838:
3728:Radioactive contamination
3581:Electromagnetic radiation
3571:
2909:
2851:
2659:
2042:. CRC Press. p. 18.
1996:Seybold, John S. (2005).
1958:Radio Systems Engineering
1861:. 1728 Software Systems.
1768:Gosling, William (1998).
1606:Radio Systems Engineering
1280:. In the transmitter, an
1276:representing data from a
944:Most listened-to programs
794:left circularly polarized
393:, represented by red band
182:communications satellites
93:electromagnetic radiation
3841:See also the categories
3779:1996 Costa Rica accident
3440:Acoustic radiation force
2903:Electromagnetic spectrum
2262:. pp. 5.116–5.119.
2141:Kitchen, Ronald (2001).
2110:Brain, M. (7 Dec 2000).
1812:Shore, Bruce W. (2020).
593:{\displaystyle \lambda }
341:Generation and reception
105:electromagnetic spectrum
3753:Radiation heat-transfer
3606:Gravitational radiation
2545:Hertz, Heinrich Rudolph
2218:. Newnes. p. 234.
1175:extremely low frequency
1074:television broadcasting
952:Physics and engineering
752:radio signal. A 1
508:{\displaystyle E=h\nu }
133:, such as time-varying
3794:1990 Zaragoza accident
3789:1984 Moroccan accident
3758:Linear energy transfer
3432:Non-ionizing radiation
2951:
2529:10.1098/rstl.1865.0008
2369:. Volumes 1–123.
2074:Siegel, Peter (2002).
1585:Television transmitter
1494:
1416:non-ionizing radiation
778:horizontally polarized
742:
719:
663:
617:
594:
560:
509:
400:
349:Animated diagram of a
327:Nobel Prize in physics
263:
145:, and are part of the
85:
42:. For other uses, see
3784:1987 Goiânia accident
3586:Synchrotron radiation
3576:Earth's energy budget
3558:Radioactive materials
3553:Particle accelerators
2950:
2407:(conference poster).
1917:ITU Radio Regulations
1552:electromagnetic field
1492:
1407:Further information:
1282:electronic oscillator
1131:multipath propagation
1092:can communicate with
833:quantum superposition
743:
720:
664:
618:
595:
561:
531:process, governed by
510:
348:
245:
221:electromagnetic waves
52:
3855:Radiation protection
3708:Radiation protection
3596:Black-body radiation
3503:Background radiation
3418:(physics and health)
2509:Maxwell, James Clerk
1736:Edwards, Stephen A.
1465:hyperthermia therapy
1162:vertically polarized
1100:Indirect propagation
786:circularly polarized
782:vertically polarized
732:
679:
630:
607:
584:
550:
490:
463:elementary particles
429:black body radiation
299:electromagnetic wave
143:astronomical objects
3825:Radiation hardening
3767:Radiation incidents
3703:Medical radiography
3662:Radiation syndrome
3616:Cherenkov radiation
3036:Extreme ultraviolet
2080:Education materials
1683:. 2016. p. 7.
1493:Radio waves symbol
1286:alternating current
1246:radio communication
1234:Radio communication
913:Internet talk radio
814:blackbody radiation
533:Maxwell's equations
427:) as part of their
321:. Italian inventor
287:Maxwell's equations
283:James Clerk Maxwell
258:radio transmitting
166:radio communication
147:blackbody radiation
3820:Radioactive source
3641:Radiation exposure
3621:Askaryan radiation
3601:Particle radiation
3485:Ionizing radiation
3041:Vacuum ultraviolet
2952:
2555:Cornell University
2405:monographs.iarc.fr
2367:monographs.iarc.fr
1646:www.britannica.com
1495:
1396:resonant frequency
1171:very low frequency
821:quantum mechanical
738:
715:
659:
613:
590:
556:
505:
401:
264:
86:
3893:Telecommunication
3862:
3861:
3843:Radiation effects
3713:Radiation therapy
3649:
3648:
3591:Thermal radiation
3528:Neutron radiation
3493:Radioactive decay
3382:
3381:
3086:Visible (optical)
2869:
2868:
2846:
2845:
2332:(Press release).
2116:HowStuffWorks.com
2112:"How Radio Works"
1673:Radio Regulations
1548:amperes per meter
1390:, similarly to a
1386:which act like a
1288:oscillating at a
1254:modulation signal
1250:radio transmitter
1126:wireless networks
1025:radio propagation
1006:
1005:
852:Part of series on
845:Radio propagation
741:{\displaystyle c}
711:
707:
655:
651:
616:{\displaystyle f}
559:{\displaystyle c}
485:Planck's relation
459:quantum mechanics
448:radio transmitter
436:electric currents
405:charged particles
323:Guglielmo Marconi
135:electric currents
127:charged particles
66:radio transmitter
16:(Redirected from
3916:
3891:
3890:
3889:
3879:
3878:
3877:
3870:
3803:Related articles
3718:Radiation damage
3543:Nuclear reactors
3428:
3409:
3402:
3395:
3386:
2973:
2971:
2964:
2957:
2896:
2889:
2882:
2873:
2862:Radio portal
2860:
2859:
2858:
2662:
2645:
2638:
2631:
2622:
2617:
2598:
2568:
2540:
2501:
2500:
2472:
2466:
2465:
2463:
2462:
2434:
2428:
2427:
2425:
2423:
2417:
2402:
2393:
2387:
2386:
2384:
2382:
2359:
2353:
2352:
2350:
2348:
2342:
2327:
2319:
2313:
2312:
2310:
2309:
2281:
2275:
2274:
2272:
2271:
2247:
2241:
2240:
2238:
2237:
2209:
2203:
2202:
2200:
2199:
2171:
2165:
2164:
2148:
2138:
2132:
2131:
2129:
2127:
2107:
2096:
2095:
2093:
2091:
2071:
2065:
2064:
2062:
2061:
2033:
2027:
2026:
2024:
2023:
1993:
1984:
1983:
1981:
1980:
1952:
1946:
1945:
1943:
1922:
1911:
1905:
1904:
1902:
1900:
1895:on 28 March 2014
1891:. Archived from
1881:
1875:
1874:
1872:
1870:
1847:
1841:
1840:
1838:
1837:
1809:
1803:
1802:
1800:
1799:
1793:
1776:
1765:
1754:
1753:
1751:
1749:
1733:
1727:
1726:
1708:
1702:
1701:
1699:
1678:
1667:
1661:
1660:
1658:
1657:
1638:
1632:
1631:
1629:
1628:
1600:
1529:
1528:
1524:
1413:Radio waves are
1138:, often causing
998:
991:
984:
868:
849:
823:property of the
802:right-hand sense
756:radio wave (mid-
747:
745:
744:
739:
724:
722:
721:
716:
709:
708:
705:
703:
702:
668:
666:
665:
660:
653:
652:
647:
640:
622:
620:
619:
614:
599:
597:
596:
591:
565:
563:
562:
557:
514:
512:
511:
506:
483:. However, from
438:, consisting of
398:
394:
392:
379:
375:
367:
365:
356:
351:half-wave dipole
279:electromagnetism
273:History of radio
178:radio navigation
120:
119:
115:
99:and the longest
95:with the lowest
55:half-wave dipole
21:
3924:
3923:
3919:
3918:
3917:
3915:
3914:
3913:
3899:
3898:
3897:
3887:
3885:
3875:
3873:
3865:
3863:
3858:
3857:
3834:
3830:Havana syndrome
3815:Nuclear physics
3798:
3762:
3655:
3645:
3631:Unruh radiation
3567:
3548:Nuclear weapons
3533:Nuclear fission
3479:
3419:
3413:
3383:
3378:
3344:
3271:
3246:
3232:
3200:
3128:
3080:
3022:
2999:
2976:
2969:
2962:
2955:
2953:
2905:
2900:
2870:
2865:
2856:
2854:
2847:
2842:
2839:
2838:300 GHz/1 mm
2837:
2827:
2824:
2822:
2812:
2809:
2807:
2797:
2794:
2793:300 MHz/1 m
2792:
2782:
2779:
2777:
2767:
2764:
2762:
2752:
2749:
2748:300 kHz/1 km
2747:
2737:
2734:
2732:
2722:
2719:
2717:
2707:
2704:
2703:300 Hz/1 Mm
2702:
2692:
2689:
2687:
2677:
2674:
2672:
2655:
2649:
2608:
2605:
2587:
2571:
2565:
2543:
2507:
2504:
2493:
2485:. p. 186.
2474:
2473:
2469:
2460:
2458:
2451:
2436:
2435:
2431:
2421:
2419:
2415:
2400:
2395:
2394:
2390:
2380:
2378:
2361:
2360:
2356:
2346:
2344:
2340:
2336:. 31 May 2011.
2325:
2321:
2320:
2316:
2307:
2305:
2298:
2283:
2282:
2278:
2269:
2267:
2249:
2248:
2244:
2235:
2233:
2226:
2211:
2210:
2206:
2197:
2195:
2188:
2173:
2172:
2168:
2161:
2140:
2139:
2135:
2125:
2123:
2109:
2108:
2099:
2089:
2087:
2086:on 20 June 2021
2073:
2072:
2068:
2059:
2057:
2050:
2035:
2034:
2030:
2021:
2019:
2012:
1995:
1994:
1987:
1978:
1976:
1969:
1954:
1953:
1949:
1941:
1935:
1920:
1913:
1912:
1908:
1898:
1896:
1883:
1882:
1878:
1868:
1866:
1849:
1848:
1844:
1835:
1833:
1826:
1811:
1810:
1806:
1797:
1795:
1791:
1785:
1774:
1767:
1766:
1757:
1747:
1745:
1735:
1734:
1730:
1723:
1710:
1709:
1705:
1697:
1691:
1676:
1669:
1668:
1664:
1655:
1653:
1640:
1639:
1635:
1626:
1624:
1617:
1602:
1601:
1597:
1593:
1580:Radio astronomy
1576:
1544:volts per meter
1540:
1526:
1522:
1521:
1453:polar molecules
1435:them, or break
1411:
1405:
1380:bandpass filter
1328:bandpass filter
1316:magnetic fields
1290:radio frequency
1242:
1236:
1224:millimeter wave
1118:cordless phones
1090:Ground stations
1086:microwave relay
1002:
923:Call-in (radio)
887:Satellite radio
847:
841:
766:
730:
729:
694:
677:
676:
641:
628:
627:
605:
604:
582:
581:
548:
547:
541:
488:
487:
396:
390:
389:
377:
373:
363:
362:
354:
343:
337:" around 1912.
275:
269:
252:magnetic fields
248:electric fields
246:Diagram of the
117:
113:
112:
53:Animation of a
47:
40:Radio Wave 96.5
32:Radio frequency
28:
23:
22:
15:
12:
11:
5:
3922:
3920:
3912:
3911:
3901:
3900:
3896:
3895:
3883:
3860:
3859:
3839:
3836:
3835:
3833:
3832:
3827:
3822:
3817:
3812:
3806:
3804:
3800:
3799:
3797:
3796:
3791:
3786:
3781:
3776:
3770:
3768:
3764:
3763:
3761:
3760:
3755:
3750:
3745:
3740:
3735:
3730:
3725:
3720:
3715:
3710:
3705:
3700:
3695:
3690:
3685:
3680:
3678:Health physics
3675:
3674:
3673:
3668:
3659:
3657:
3651:
3650:
3647:
3646:
3644:
3643:
3638:
3636:Dark radiation
3633:
3628:
3626:Bremsstrahlung
3623:
3618:
3613:
3608:
3603:
3598:
3593:
3588:
3583:
3578:
3572:
3569:
3568:
3566:
3565:
3560:
3555:
3550:
3545:
3540:
3538:Nuclear fusion
3535:
3530:
3525:
3520:
3515:
3510:
3508:Alpha particle
3505:
3500:
3495:
3489:
3487:
3481:
3480:
3478:
3477:
3472:
3467:
3462:
3457:
3452:
3447:
3442:
3436:
3434:
3425:
3421:
3420:
3414:
3412:
3411:
3404:
3397:
3389:
3380:
3379:
3377:
3376:
3371:
3366:
3361:
3355:
3353:
3346:
3345:
3343:
3342:
3337:
3332:
3327:
3322:
3317:
3312:
3307:
3302:
3297:
3292:
3287:
3281:
3279:
3273:
3272:
3270:
3269:
3264:
3259:
3254:
3249:
3244:
3240:
3235:
3230:
3226:
3221:
3216:
3210:
3208:
3202:
3201:
3199:
3198:
3193:
3188:
3166:
3161:
3138:
3136:
3130:
3129:
3127:
3126:
3121:
3116:
3111:
3106:
3101:
3096:
3090:
3088:
3082:
3081:
3079:
3078:
3073:
3068:
3063:
3058:
3053:
3048:
3043:
3038:
3032:
3030:
3024:
3023:
3021:
3020:
3015:
3009:
3007:
3001:
3000:
2998:
2997:
2992:
2986:
2984:
2978:
2977:
2975:
2974:
2941:
2936:
2931:
2926:
2921:
2916:
2910:
2907:
2906:
2901:
2899:
2898:
2891:
2884:
2876:
2867:
2866:
2852:
2849:
2848:
2844:
2843:
2830:
2828:
2823:30 GHz/10 mm
2815:
2813:
2800:
2798:
2785:
2783:
2778:30 MHz/10 m
2770:
2768:
2755:
2753:
2740:
2738:
2733:30 kHz/10 km
2725:
2723:
2710:
2708:
2695:
2693:
2688:30 Hz/10 Mm
2680:
2678:
2665:
2660:
2657:
2656:
2652:Radio spectrum
2650:
2648:
2647:
2640:
2633:
2625:
2619:
2618:
2604:
2603:External links
2601:
2600:
2599:
2585:
2569:
2563:
2541:
2503:
2502:
2491:
2467:
2449:
2429:
2388:
2373:. 9 Nov 2018.
2354:
2314:
2296:
2276:
2242:
2224:
2204:
2186:
2166:
2159:
2133:
2097:
2066:
2048:
2028:
2010:
1985:
1968:978-1316785164
1967:
1947:
1933:
1923:. Geneva, CH:
1906:
1876:
1842:
1824:
1804:
1783:
1755:
1728:
1721:
1703:
1689:
1679:. Geneva, CH:
1662:
1648:. 2024-07-26.
1633:
1616:978-1316785164
1615:
1594:
1592:
1589:
1588:
1587:
1582:
1575:
1572:
1556:field strength
1539:
1536:
1534:of the waves.
1457:microwave oven
1437:chemical bonds
1404:
1401:
1384:tuned circuits
1366:, measured in
1356:microprocessor
1348:display screen
1324:radio receiver
1274:digital signal
1238:Main article:
1235:
1232:
1228:terahertz band
1215:
1214:
1211:radio amateurs
1182:
1145:
1144:
1143:
1122:walkie-talkies
1004:
1003:
1001:
1000:
993:
986:
978:
975:
974:
973:
972:
967:
962:
954:
953:
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932:
928:
927:
926:
925:
920:
915:
910:
902:
901:
900:Uses and forms
897:
896:
895:
894:
892:Internet radio
889:
884:
875:
874:
870:
869:
861:
860:
854:
853:
843:Main article:
840:
837:
809:dipole antenna
798:magnetic field
774:electric field
765:
762:
737:
728:Equivalently,
726:
725:
714:
701:
697:
693:
690:
687:
684:
670:
669:
658:
650:
645:
638:
635:
612:
589:
555:
545:speed of light
540:
537:
504:
501:
498:
495:
452:radio receiver
407:when they are
386:standing waves
366:, green arrows
359:electric field
342:
339:
307:standing waves
303:Heinrich Hertz
295:magnetic field
271:Main article:
268:
265:
233:radio spectrum
162:radio receiver
123:speed of light
91:are a type of
82:speed of light
62:electric field
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
3921:
3910:
3907:
3906:
3904:
3894:
3884:
3882:
3872:
3868:
3856:
3852:
3848:
3847:Radioactivity
3844:
3837:
3831:
3828:
3826:
3823:
3821:
3818:
3816:
3813:
3811:
3808:
3807:
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3652:
3642:
3639:
3637:
3634:
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3629:
3627:
3624:
3622:
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3617:
3614:
3612:
3609:
3607:
3604:
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3599:
3597:
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3589:
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3554:
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3539:
3536:
3534:
3531:
3529:
3526:
3524:
3521:
3519:
3516:
3514:
3513:Beta particle
3511:
3509:
3506:
3504:
3501:
3499:
3498:Cluster decay
3496:
3494:
3491:
3490:
3488:
3486:
3482:
3476:
3473:
3471:
3468:
3466:
3463:
3461:
3458:
3456:
3453:
3451:
3448:
3446:
3443:
3441:
3438:
3437:
3435:
3433:
3429:
3426:
3424:Main articles
3422:
3417:
3410:
3405:
3403:
3398:
3396:
3391:
3390:
3387:
3375:
3372:
3370:
3367:
3365:
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3354:
3351:
3347:
3341:
3338:
3336:
3333:
3331:
3328:
3326:
3323:
3321:
3318:
3316:
3313:
3311:
3308:
3306:
3303:
3301:
3298:
3296:
3293:
3291:
3288:
3286:
3283:
3282:
3280:
3278:
3274:
3268:
3265:
3263:
3260:
3258:
3255:
3253:
3250:
3248:
3241:
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3236:
3234:
3227:
3225:
3222:
3220:
3217:
3215:
3212:
3211:
3209:
3207:
3203:
3197:
3194:
3192:
3189:
3186:
3182:
3178:
3174:
3170:
3167:
3165:
3162:
3159:
3155:
3151:
3147:
3143:
3140:
3139:
3137:
3135:
3131:
3125:
3122:
3120:
3117:
3115:
3112:
3110:
3107:
3105:
3102:
3100:
3097:
3095:
3092:
3091:
3089:
3087:
3083:
3077:
3074:
3072:
3069:
3067:
3064:
3062:
3059:
3057:
3054:
3052:
3049:
3047:
3044:
3042:
3039:
3037:
3034:
3033:
3031:
3029:
3025:
3019:
3016:
3014:
3011:
3010:
3008:
3006:
3002:
2996:
2993:
2991:
2988:
2987:
2985:
2983:
2979:
2972:
2968:
2961:
2949:
2945:
2942:
2940:
2937:
2935:
2932:
2930:
2927:
2925:
2922:
2920:
2917:
2915:
2912:
2911:
2908:
2904:
2897:
2892:
2890:
2885:
2883:
2878:
2877:
2874:
2864:
2863:
2850:
2841:
2840:3 THz/0.1 mm
2836:
2835:
2829:
2826:
2825:300 GHz/1 mm
2821:
2820:
2814:
2811:
2810:30 GHz/10 mm
2808:3 GHz/100 mm
2806:
2805:
2799:
2796:
2795:3 GHz/100 mm
2791:
2790:
2784:
2781:
2776:
2775:
2769:
2766:
2763:3 MHz/100 m
2761:
2760:
2754:
2751:
2746:
2745:
2739:
2736:
2735:300 kHz/1 km
2731:
2730:
2724:
2721:
2720:30 kHz/10 km
2718:3 kHz/100 km
2716:
2715:
2709:
2706:
2705:3 kHz/100 km
2701:
2700:
2694:
2691:
2686:
2685:
2679:
2676:
2673:3 Hz/100 Mm
2671:
2670:
2664:
2663:
2658:
2653:
2646:
2641:
2639:
2634:
2632:
2627:
2626:
2623:
2615:
2611:
2610:"Radio Waves"
2607:
2606:
2602:
2596:
2592:
2588:
2586:9780792307754
2582:
2578:
2574:
2570:
2566:
2564:9781429740364
2560:
2556:
2552:
2551:
2546:
2542:
2538:
2534:
2530:
2526:
2522:
2518:
2514:
2510:
2506:
2505:
2498:
2494:
2492:9780893242367
2488:
2484:
2480:
2479:
2471:
2468:
2456:
2452:
2450:9781351453370
2446:
2442:
2441:
2433:
2430:
2414:
2410:
2406:
2399:
2392:
2389:
2376:
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2364:
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2339:
2335:
2331:
2324:
2318:
2315:
2303:
2299:
2297:9780471284543
2293:
2289:
2288:
2280:
2277:
2265:
2261:
2257:
2253:
2246:
2243:
2231:
2227:
2221:
2217:
2216:
2208:
2205:
2193:
2189:
2183:
2179:
2178:
2170:
2167:
2162:
2156:
2152:
2147:
2146:
2137:
2134:
2121:
2117:
2113:
2106:
2104:
2102:
2098:
2085:
2081:
2077:
2070:
2067:
2055:
2051:
2049:9781351356367
2045:
2041:
2040:
2032:
2029:
2017:
2013:
2007:
2003:
1999:
1992:
1990:
1986:
1974:
1970:
1964:
1960:
1959:
1951:
1948:
1940:
1936:
1934:9789261191214
1930:
1926:
1919:
1918:
1910:
1907:
1894:
1890:
1886:
1880:
1877:
1864:
1860:
1856:
1854:
1846:
1843:
1831:
1827:
1825:9780192607645
1821:
1817:
1816:
1808:
1805:
1790:
1786:
1780:
1773:
1772:
1764:
1762:
1760:
1756:
1743:
1739:
1732:
1729:
1724:
1722:0-521-00585-X
1718:
1714:
1707:
1704:
1696:
1692:
1690:9789261191214
1686:
1682:
1675:
1674:
1666:
1663:
1651:
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1637:
1634:
1622:
1618:
1612:
1608:
1607:
1599:
1596:
1590:
1586:
1583:
1581:
1578:
1577:
1573:
1571:
1568:
1564:
1563:power density
1559:
1557:
1553:
1549:
1545:
1537:
1535:
1533:
1519:
1514:
1512:
1506:
1504:
1500:
1491:
1487:
1484:
1483:
1478:
1474:
1468:
1466:
1462:
1458:
1454:
1450:
1446:
1442:
1438:
1434:
1430:
1426:
1422:
1418:
1417:
1410:
1402:
1400:
1397:
1393:
1389:
1385:
1381:
1377:
1373:
1369:
1365:
1359:
1357:
1353:
1349:
1345:
1341:
1337:
1333:
1329:
1325:
1319:
1317:
1313:
1309:
1305:
1301:
1297:
1296:
1292:, called the
1291:
1287:
1284:generates an
1283:
1279:
1275:
1271:
1267:
1263:
1259:
1255:
1251:
1247:
1241:
1233:
1231:
1229:
1225:
1220:
1212:
1208:
1204:
1200:
1196:
1192:
1188:
1187:
1183:
1180:
1176:
1172:
1167:
1166:surface waves
1163:
1159:
1155:
1151:
1150:
1146:
1141:
1137:
1133:
1132:
1127:
1123:
1119:
1115:
1111:
1107:
1106:
1101:
1098:
1097:
1095:
1091:
1087:
1083:
1082:dish antennas
1079:
1075:
1071:
1067:
1063:
1059:
1058:
1057:Line of sight
1054:
1053:
1052:
1050:
1046:
1042:
1038:
1034:
1030:
1026:
1023:The study of
1021:
1019:
1015:
1011:
999:
994:
992:
987:
985:
980:
979:
977:
976:
971:
968:
966:
963:
961:
958:
957:
956:
955:
950:
945:
942:
940:
939:Radio station
937:
936:
935:
934:
929:
924:
921:
919:
916:
914:
911:
909:
906:
905:
904:
903:
898:
893:
890:
888:
885:
882:
879:
878:
877:
876:
871:
867:
863:
862:
859:
855:
851:
850:
846:
838:
836:
834:
830:
827:called their
826:
822:
817:
815:
810:
805:
803:
799:
795:
791:
787:
783:
779:
775:
771:
763:
761:
759:
755:
751:
735:
712:
699:
695:
691:
688:
685:
682:
675:
674:
673:
656:
648:
643:
636:
633:
626:
625:
624:
610:
603:
587:
580:
575:
573:
569:
553:
546:
538:
536:
534:
530:
526:
522:
518:
502:
499:
496:
493:
486:
482:
478:
474:
470:
469:
464:
460:
455:
453:
449:
445:
441:
437:
432:
430:
426:
422:
418:
414:
410:
406:
387:
383:
376:and negative
371:
360:
352:
347:
340:
338:
336:
335:Hertzian wave
332:
328:
324:
320:
316:
312:
308:
304:
300:
296:
292:
288:
284:
280:
274:
266:
261:
257:
253:
249:
244:
240:
238:
234:
230:
226:
222:
218:
214:
209:
207:
206:line of sight
203:
199:
195:
191:
187:
183:
179:
175:
171:
167:
163:
159:
155:
150:
148:
144:
140:
136:
132:
128:
124:
110:
106:
102:
98:
94:
90:
83:
79:
75:
71:
67:
63:
59:
56:
51:
45:
41:
37:
33:
19:
3851:Radiobiology
3733:Radiobiology
3693:Laser safety
3469:
2954:
2943:
2853:
2832:
2831:
2817:
2816:
2802:
2801:
2787:
2786:
2780:300 MHz/1 m
2772:
2771:
2765:30 MHz/10 m
2757:
2756:
2750:3 MHz/100 m
2742:
2741:
2727:
2726:
2712:
2711:
2697:
2696:
2690:300 Hz/1 Mm
2682:
2681:
2675:30 Hz/10 Mm
2667:
2666:
2576:
2549:
2520:
2516:
2477:
2470:
2459:. Retrieved
2439:
2432:
2420:. Retrieved
2404:
2391:
2379:. Retrieved
2366:
2357:
2345:. Retrieved
2329:
2317:
2306:. Retrieved
2286:
2279:
2268:. Retrieved
2255:
2245:
2234:. Retrieved
2214:
2207:
2196:. Retrieved
2176:
2169:
2144:
2136:
2124:. Retrieved
2115:
2088:. Retrieved
2084:the original
2079:
2069:
2058:. Retrieved
2038:
2031:
2020:. Retrieved
2001:
1977:. Retrieved
1957:
1950:
1916:
1909:
1897:. Retrieved
1893:the original
1879:
1867:. Retrieved
1858:
1852:
1845:
1834:. Retrieved
1814:
1807:
1796:. Retrieved
1770:
1746:. Retrieved
1731:
1712:
1706:
1672:
1665:
1654:. Retrieved
1645:
1636:
1625:. Retrieved
1605:
1598:
1562:
1560:
1547:
1543:
1541:
1518:Faraday cage
1515:
1507:
1496:
1480:
1477:permittivity
1469:
1449:space heater
1414:
1412:
1360:
1320:
1295:carrier wave
1293:
1270:video camera
1266:video signal
1258:audio signal
1256:, can be an
1243:
1216:
1184:
1149:Ground waves
1147:
1129:
1109:
1103:
1099:
1055:
1037:polarization
1022:
1007:
970:Radio signal
931:Developments
818:
806:
770:polarization
767:
764:Polarization
727:
671:
576:
572:permittivity
568:permeability
542:
466:
456:
433:
415:produced by
402:
388:of voltage (
334:
330:
319:polarization
276:
213:interference
210:
194:ground waves
170:broadcasting
151:
131:acceleration
88:
87:
3475:Ultraviolet
3470:Radio waves
3369:Medium wave
3046:Lyman-alpha
3028:Ultraviolet
2967:wavelengths
2960:frequencies
2924:Ultraviolet
2573:Rawer, Karl
2523:: 459–512.
2330:www.iarc.fr
1855:Calculator"
1538:Measurement
1473:resistivity
1392:tuning fork
1378:(GHz). The
1340:loudspeaker
1336:demodulator
1191:medium wave
1154:medium wave
1114:cell phones
1105:diffraction
1080:. By using
1066:cell phones
1049:radio bands
1041:diffraction
1018:diffraction
1010:propagation
965:Radio tower
960:Radio waves
918:Music radio
413:radio noise
409:accelerated
315:diffraction
225:frequencies
211:To prevent
154:transmitter
129:undergoing
101:wavelengths
97:frequencies
89:Radio waves
44:Radio Waves
18:Radio waves
3909:Radio wave
3656:and health
3654:Radiation
3523:Cosmic ray
3350:Wavelength
3206:Microwaves
3018:Hard X-ray
3013:Soft X-ray
2982:Gamma rays
2914:Gamma rays
2461:2018-02-15
2308:2018-02-14
2270:2019-08-16
2236:2018-02-14
2225:0750672447
2198:2018-02-14
2187:0471752045
2160:0750643552
2060:2021-05-20
2022:2017-02-03
2011:0471743682
1979:2020-11-19
1836:2021-12-04
1798:2021-10-28
1784:0750637412
1656:2024-09-22
1627:2020-11-19
1591:References
1532:wavelength
1482:skin depth
1441:DNA damage
1262:microphone
1203:ionosphere
1173:(VLF) and
1110:reflection
1094:satellites
1045:absorption
1033:refraction
1029:reflection
1014:wavelength
908:Talk radio
883:(overland)
579:wavelength
539:Properties
425:microwaves
382:wavelength
331:radio wave
311:refraction
237:microwaves
198:ionosphere
3810:Half-life
3683:Dosimetry
3518:Gamma ray
3465:Microwave
3455:Starlight
3416:Radiation
3364:Shortwave
3359:Microwave
2939:Microwave
2537:186207827
1567:far field
1503:cataracts
1499:waveguide
1461:diathermy
1429:molecules
1421:electrons
1388:resonator
1376:gigahertz
1374:(MHz) or
1372:megahertz
1368:kilohertz
1364:frequency
1332:amplifies
1308:electrons
1219:microwave
1195:shortwave
1136:interfere
754:megahertz
706: m/s
692:×
686:≈
634:λ
602:frequency
588:λ
529:classical
503:ν
440:electrons
417:lightning
370:electrons
180:systems,
139:lightning
109:gigahertz
3903:Category
3460:Sunlight
3445:Infrared
3374:Longwave
3134:Infrared
2934:Infrared
2595:26257685
2575:(1993).
2547:(1893).
2511:(1865).
2497:Archived
2455:Archived
2413:Archived
2375:Archived
2338:Archived
2302:Archived
2264:Archived
2230:Archived
2192:Archived
2120:Archived
2054:Archived
2016:Archived
1973:Archived
1939:Archived
1927:. 2016.
1863:Archived
1859:1728.org
1830:Archived
1789:Archived
1748:13 April
1742:Archived
1695:Archived
1650:Archived
1621:Archived
1574:See also
1445:infrared
1433:ionizing
1352:computer
1344:earphone
1312:electric
1300:modulate
1278:computer
1186:Skywaves
1158:longwave
481:in phase
473:coherent
291:electric
256:monopole
250:(E) and
202:skywaves
190:diffract
78:negative
76:(+) and
74:positive
3867:Portals
3671:chronic
2965:longer
2958:higher
2929:Visible
1525:⁄
1370:(kHz),
1304:antenna
1272:, or a
1062:horizon
825:photons
758:AM band
468:photons
465:called
444:antenna
260:antenna
158:antenna
116:⁄
103:in the
58:antenna
3853:, and
3267:L band
3262:S band
3257:C band
3252:X band
3238:K band
3224:Q band
3219:V band
3214:W band
3119:Orange
3114:Yellow
3094:Violet
3005:X-rays
2919:X-rays
2593:
2583:
2561:
2535:
2489:
2447:
2294:
2260:US EPA
2222:
2184:
2157:
2126:11 Sep
2090:19 May
2046:
2008:
1965:
1931:
1899:15 Jan
1869:15 Jan
1822:
1781:
1719:
1687:
1613:
1140:fading
1124:, and
1043:, and
710:
689:2.9979
672:where
654:
517:joules
357:. The
317:, and
3881:Radio
3666:acute
3563:X-ray
3450:Light
3352:types
3277:Radio
3173:Bands
3146:Bands
3109:Green
2944:Radio
2654:(ITU)
2533:S2CID
2422:9 Jan
2416:(PDF)
2401:(PDF)
2381:9 Jan
2347:9 Jan
2341:(PDF)
2326:(PDF)
2153:–65.
1942:(PDF)
1921:(PDF)
1853:Ultra
1792:(PDF)
1775:(PDF)
1698:(PDF)
1677:(PDF)
1425:atoms
1423:from
1240:Radio
1189:: At
1078:radar
881:Radio
873:Forms
858:Radio
750:hertz
525:maser
477:laser
457:From
174:radar
3247:band
3233:band
3191:LWIR
3169:MWIR
3164:SWIR
3104:Cyan
3099:Blue
2614:NASA
2591:OCLC
2581:ISBN
2559:ISBN
2487:ISBN
2445:ISBN
2424:2019
2409:IARC
2383:2019
2371:IARC
2349:2019
2292:ISBN
2220:ISBN
2182:ISBN
2155:ISBN
2128:2009
2092:2021
2044:ISBN
2006:ISBN
1963:ISBN
1929:ISBN
1901:2018
1889:NRAO
1871:2018
1820:ISBN
1779:ISBN
1750:2021
1717:ISBN
1685:ISBN
1611:ISBN
1475:and
1314:and
1264:, a
1199:ions
1193:and
1156:and
1108:and
1076:and
829:spin
577:The
570:and
293:and
239:.
176:and
141:and
3340:ELF
3335:SLF
3330:ULF
3325:VLF
3305:VHF
3300:UHF
3295:SHF
3290:EHF
3285:THF
3196:FIR
3142:NIR
3124:Red
3076:UVA
3071:UVB
3066:UVC
3061:NUV
3056:MUV
3051:FUV
2834:THF
2819:EHF
2804:SHF
2789:UHF
2774:VHF
2714:VLF
2699:ULF
2684:SLF
2669:ELF
2525:doi
2521:155
2483:NAB
2334:WHO
1681:ITU
1530:of
1505:.
1427:or
1354:or
1342:or
1244:In
1217:At
378:(−)
374:(+)
229:GHz
223:of
3905::
3849:,
3845:,
3320:LF
3315:MF
3310:HF
3183:,
3179:,
3175::
3156:,
3152:,
3148::
2759:HF
2744:MF
2729:LF
2589:.
2557:.
2531:.
2519:.
2515:.
2495:.
2453:.
2411:.
2403:.
2365:.
2328:.
2300:.
2258:.
2254:.
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