Radio frequency (RF, rf, or r.f.) is a representation of the oscillation rate of the electromagnetic spectrum measured in hertz (Hz). One hertz is equal to one cycle per second, and most radio frequencies are measured in hundreds, thousands, millions, or billions of cycles per second. Radio frequencies are able to carry data over electromagnetic fields via specialized antennas and transmitters.
Aside from radio receivers, many kinds of technologies rely on RF field propagation to transmit and receive data. These include mobile phones, remote controls, microwave ovens, computers, smart home devices, satellites, and transceivers, among others. Bluetooth and wireless LANs (WLANs) also operate using radio frequencies.
RF range
The radio frequency spectrum was given a formal naming structure by the International Telecommunications Union (ITU) in the 1800s. The language that designates each band in the spectrum is very specific and should be used carefully. The RF spectrum is as follows:
- Tremendously low frequency (TLF): < 3Hz
- Extremely low frequency (ELF): 3-30 Hz
- Super low frequency (SLF): 30-300 Hz
- Ultra-low frequency (ULF): 300-3000 Hz (3 kHz)
- Very low frequency (VLF): 3-30 kHz
- Low frequency (LF): 30-300 kHz
- Medium frequency (MF): 300-3000 kHz (3 MHz)
- High frequency (HF): 3-30 MHz
- Very high frequency (VHF): 30-300 MHz
- Ultra-high frequency (UHF): 300-3000 MHz (3 GHz)
- Super high frequency (SHF): 3-30 GHz
- Extremely high frequency (EHF): 30-300 GHz
- Tremendously high frequency (THF): 300-3000 GHz (3 THz)
As indicated in the list above, one kilohertz (kHz) is equal to 1,000 hertz (Hz), one megahertz (MHz) is equal to 1,000 kilohertz, one gigahertz (GHz) is equal to 1,000 megahertz, and one terahertz (THz) is equal to 1,000 gigahertz.
How do radio frequencies affect the human body?
Higher radio frequencies are thought to have cancerous effects on the human body after repeated prolonged periods of exposure. Most research organizations have reported that there is either insufficient evidence to establish a causal relationship between radio frequencies and cancer or that there is the potential for radio frequency radiation to have carcinogenic effects. However, this is an ongoing field of biomedical research.