Radio frequency

Radio frequency, or RF, is a carrier, or alternating current with or without a signal, at a frequency that can radiate, or propagate, if not shielded. Such frequencies account for the following parts of the electromagnetic spectrum:

Very low frequency (VLF): 3-30 kHz
Low frequency (LF): 30-300 kHz
Medium frequency (MF): 300-3000 kHz
High frequency (HF): 3-30 MHz
Very high frequency (VHF): 30-300 MHz
Ultra high frequency (UHF): 300-3000 MHz
Super high frequency (SHF): 3-30 GHz
Extremely high frequency (EHF): 30-300 GHz

Note: above 300 GHz, the absorption of electromagnetic radiation by Earth's atmosphere is so great that the atmosphere is effectively opaque to higher frequencies of electromagnetic radiation, until the atmosphere becomes transparent again in the so-called infrared and optical window freqency ranges.

Analog signals that are not RF include IF (intermediate frequency) and AF (audio frequency, 20-20000 Hz).

Electrical connectors designed to work at radio frequencies are known as RF connectors. RF is also the name of a standard audio/video connector, also called BNC (BayoNet Connector).

Named Frequency Bands

Microwave (US)

See also:



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