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HF-UHV-VHF Frequency Bands and Features

Frequency values ​​were divided into certain bands according to their characters and usage.r.

DEFINITION

ABBREVIATION
FREQUENCY
WAVELENGTH

Very Low Frequency

VLF

3 kHz-30 kHz

100 km-10 km

Low Frequency

LF

3O kHz-300 kHz

10km-1 km

Mediurn Frequency

MF

300 kHz-3 MHz

1 km-l00m

High Frequency

HF

3 MHz-3O MHz

100 m-10 m

Very High Frequency

VHF

30 MHz-3O0 MHz

10 m-1 m

Ultra High Frequency

UHF

300 MHz-3 MHz

100cm-10cm

Super High Frequency

SHF

3 GHz-30 GHz

10cm-1 cm

Extremely High Frequency

EHF

30 GHz-300 GHz

1 cm-1 mm

 

Properties of Frequency Bands

VLF

PUBLICATION: Earth and sky waves

RANGE: Ground waves are dominant and can reach distances farther than 4000 NM. Mountains do not interfere with the propagation of low frequency waves

ANTENNA: Antenna dimensions are quite large (depending on long wavelength)

POWER: In the ranks of kW depending on the weakening of the ground waves.

USAGE: OMEGA, commercial telegraph shots, radio broadcasts

NOISE: They are highly affected by static noise and weather conditions of the air.

LF

PUBLICATION: Earth and sky waves (sky waves only dominate at night)

RANGE: 1 500 NM with ground waves, 3000 NM with sky waves

ANTENNA: 50 m. wide dipole in neck

POWER: Within the range of several kW depending on the range

USAGE: NDB, LORAN

NOISE: High enough, sensitive to weather conditions

MF

PUBLICATION: Earth and sky waves in general, direct waves in some places

RANGE: 300 NM above ground, 1000 NM above water

ANTENNA: A few meters of dipole

POWER: At the order of several hundred watts

USAGE: NDB, LORAN, ground to ground or rarely air to ground communication

NOISE: High, Fading event

HF

PUBLICATION: Generally, sky and direct waves are dominant. It can be seen in ground waves up to 100 NM.

RANGE: Silent zone between 300 NM during the day and 100 NM up to 150 NM during the night by means of sky waves.

ANTENNA: Medium-sized dipole

POWER: 100-200 W depending on the range

USAGE: Long range to ground and air to ground communication

NOISE: Moderate

VHF

PUBLICATION: Direct waves

RANGE: 100-300 NM, related to altitude receiving

ANTENNA: 1 m dipole

POWER: Within the range of several 10 W

USAGE: VOR, ILS Localiser, Markers, VDF, FM radio and television broadcasting, wireless communication.

NOISE: Minimum

UHF

PUBLICATION: Direct waves

RANGE: More than 200 NM, depending on altitude

ANTENNA: 20-30 cm. in size

POWER: A few watts

USAGE: DME, ILS Glide Path, TACAN, military communication, GPS

NOISE: At negligible levels

SHF and EHF

PUBLICATION: Direct waves

RANGE: More than 200 NM, depending on altitude

ANTENNA: A few centimeters in size

POWER: At the order of several watts

USAGE: MLS, Radio altimeter, all radar systems

NOISE: At negligible levels.

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