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Classification of radio wavesRadio waves are electromagnetic waves. Electromagnetic waves include waves such as X rays, ultraviolet light,visible light, infrared rays and so on, but you probably imagine radio waves to be quite different from these waves. Of the various kinds of electromagnetic waves,

radio waves have a longer wave length than infrared rays, and are defined by the Radio Law as 'electromagnetic waves with a frequency of less than 3,000 GHz (3

THz)'.

Ultralowfrequency radiowaves

below 3kHz

radio waves

3kHz~3THz

infrared rays

3THz~380THz

visible light

380THz~790THz

ultraviolet light

790THz~105THz

X rays

105THz~107THz

rays

above 107THz

*K:kilo 1*103, M:mega 1*106, G:giga 1*109, T:tera 1*1012

Names of radio waves Frequency Wave length Principal

applications

VLF(Very LowFrequency)

3kHz ~ 30kHz 100km ~ 10km

LF(Low Frequency) 30kHz ~ 300kHz 10km ~ 1km Vessel /

Airplane

beacon

MF(Medium Frequency) 300kHz ~ 3MHz 1km ~ 100m AM radio,

Marine radio,

Amateur radio

HF(High Frequency) 3MHz ~ 30MHz 100m ~ 10m Shortwave

broadcasting,

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Marine / Air

radio,

Amateur radio

VHF(Very High

Frequency)

30MHz ~ 300MHz 10m ~ 1m TV, FM, Fire

radio, Police

radio, Disaster

PA radio

network

UHF(Ultra High

Frequency)

300MHz ~ 3GHz 1m ~ 10cm Low power

radio, Mobile-

phone, Taxi

radio,Amateur

radio, TV,

Wireless LAN

SHF(Super High

Frequency)

3GHz ~ 30GHz 10cm ~ 1cm Satellite

broadcasting,

Radar

EHF(Extremely HighFrequency)

30GHz ~ 300GHz 1cm ~ 1mm Satellitebroadcasting,

Radio

astronomy,

Radar

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submillimeter waves 300GHz ~ 3THz 1mm ~ 0.1mm

Radio frequencies and their primary mode of propagation

Band Frequency Wavelength Propagation via

ELF

Extremely

Low

Frequency

3300Hz 1000-100,000 km

VLFVery Low

Frequency330kHz 10010 km Guided between the earth and theionosphere.

LFLow

Frequency

30

300kHz

101 km

Guided between the earth and theD layerof the ionosphere.

Surface waves.

MFMedium

Frequency

300

3000kHz1000100 m

Surface waves.

E,F layerionospheric refraction at night, when D layer absorption weakens.

HF

High

Frequency

(Short

Wave)

330MHz 10010 m

E layerionospheric refraction.

F1,F2layer ionospheric refraction.

VHFVery High

Frequency

30

300MHz101 m

InfrequentE ionospheric (Es) refraction.UncommonlyF2layer ionosphericrefraction during high sunspot activity up to 50 MHz and rarely to 80 MHz.

Generally direct wave. Sometimestropospheric ducting.

UHFUltra High

Frequency

300

3000MHz10010 cm Direct wave.Sometimestropospheric ducting.

http://en.wikipedia.org/wiki/Extremely_low_frequencyhttp://en.wikipedia.org/wiki/Extremely_low_frequencyhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Very_low_frequencyhttp://en.wikipedia.org/wiki/Very_low_frequencyhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Ionospherehttp://en.wikipedia.org/wiki/Ionospherehttp://en.wikipedia.org/wiki/Ionospherehttp://en.wikipedia.org/wiki/Low_frequencyhttp://en.wikipedia.org/wiki/Low_frequencyhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/D_layerhttp://en.wikipedia.org/wiki/D_layerhttp://en.wikipedia.org/wiki/D_layerhttp://en.wikipedia.org/wiki/Surface_wavehttp://en.wikipedia.org/wiki/Surface_wavehttp://en.wikipedia.org/wiki/Medium_frequencyhttp://en.wikipedia.org/wiki/Medium_frequencyhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/F_layerhttp://en.wikipedia.org/wiki/F_layerhttp://en.wikipedia.org/wiki/F_layerhttp://en.wikipedia.org/wiki/High_frequencyhttp://en.wikipedia.org/wiki/High_frequencyhttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/E_layerhttp://en.wikipedia.org/wiki/E_layerhttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/Very_high_frequencyhttp://en.wikipedia.org/wiki/Very_high_frequencyhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Sporadic_E_propagationhttp://en.wikipedia.org/wiki/Sporadic_E_propagationhttp://en.wikipedia.org/wiki/Sporadic_E_propagationhttp://en.wikipedia.org/wiki/Sporadic_E_propagationhttp://en.wikipedia.org/wiki/Sporadic_E_propagationhttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/Ultra_high_frequencyhttp://en.wikipedia.org/wiki/Ultra_high_frequencyhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Line-of-sight_propagationhttp://en.wikipedia.org/wiki/Line-of-sight_propagationhttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/Line-of-sight_propagationhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Ultra_high_frequencyhttp://en.wikipedia.org/wiki/Tropospheric_ductinghttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/Sporadic_E_propagationhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Very_high_frequencyhttp://en.wikipedia.org/wiki/F2_propagationhttp://en.wikipedia.org/wiki/E_layerhttp://en.wikipedia.org/wiki/Megahertzhttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/Shortwavehttp://en.wikipedia.org/wiki/High_frequencyhttp://en.wikipedia.org/wiki/F_layerhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Medium_frequencyhttp://en.wikipedia.org/wiki/Surface_wavehttp://en.wikipedia.org/wiki/D_layerhttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Low_frequencyhttp://en.wikipedia.org/wiki/Ionospherehttp://en.wikipedia.org/wiki/Kilohertzhttp://en.wikipedia.org/wiki/Very_low_frequencyhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Extremely_low_frequency

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SHF

Super

High

Frequency

330GHz 101 cm Direct wave.

EHF

Extremely

High

Frequency

30

300GHz10

1 mm Direct wave limited by absorption.

http://en.wikipedia.org/wiki/Super_high_frequencyhttp://en.wikipedia.org/wiki/Super_high_frequencyhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Extremely_high_frequencyhttp://en.wikipedia.org/wiki/Extremely_high_frequencyhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Extremely_high_frequencyhttp://en.wikipedia.org/wiki/Gigahertzhttp://en.wikipedia.org/wiki/Super_high_frequency