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
- Band III - 174-245 MHz
- ISM band......specific frequencies vary
Microwave (US)
- L-band........1 to 2GHz
- S-band........2 to 4GHz
- C-band........4 to 8GHz
- X-band........8 to 12GHz
- Ku-band......12 to 18GHz
- K-band.......18 to 26GHz
- Ka-band......26 to 40GHz
- V-band.......40 to 75Ghz
- W-band.......75 to 110GHz
See also: