Back تردد منخفض Arabic Baixa freqüència (radiofreqüència) Catalan Dlouhé vlny Czech Langbølger Danish Langwelle German Longondo Esperanto Baja frecuencia Spanish بسامد پایین Persian LF (taajuusalue) Finnish Basse fréquence French
Frequency range | 30–300 kHz |
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Wavelength range | 10–1 km |
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Low frequency (LF) is the ITU designation[1][2] for radio frequencies (RF) in the range of 30–300 kHz. Since its wavelengths range from 10–1 km, respectively, it is also known as the kilometre band or kilometre waves.
LF radio waves exhibit low signal attenuation, making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, part of the LF spectrum is used for AM broadcasting as the "longwave" band. In the western hemisphere, its main use is for aircraft beacons, navigation (LORAN, mostly defunct), information, and weather systems. A number of time signal broadcasts also use this band. The main mode of transmission used in this band is ground waves, in which LF radio waves travel just above the Earth's surface, following the terrain. LF ground waves can travel over hills, and can travel far beyond the horizon, up to several hundred kilometers from the transmitter.
- ^ US Federal Standard 1037B: Telecommunications, Glossary of Telecommunications Terms. Office of Technology Standards, General Services Administration. 3 June 1991. pp. S-18.
- ^ Final Acts WRC-15 (PDF). World Radiocommunication Conference. Geneva, Switzerland: International Telecommunications Union. 2015. p. 4. Retrieved 12 January 2025.