Translations:Observations/Radio wave propagation/22/en
| Band | Frequency | Wavelength | Propagation Method / Usage |
|---|---|---|---|
| ELF | 3–30 Hz | 100,000-10,000 km 62,137-6,213 miles |
Guided between the Earth and the ionosphere. This frequency band is used for underwater communication, especially for pipeline transportation. |
| SLF | 30–300 Hz | 10,000-1,000 km 6,213-621 miles |
Guided between the Earth and the ionosphere. Used for submarine communications and in the electric grid (not as a transmitted wave). |
| ULF | 0.3–3 kHz | 1,000-100 km 621-62 miles |
Guided between the Earth and the ionosphere. Used for mining communications and military applications. |
| VLF | 3–30 kHz | 100-10 km 62-6.2 miles |
Guided between the Earth and the ionosphere and ground wave propagation. As this band of frequency exhibits penetration properties through dirt and rock, it is used for geophysics applications, navigation, wireless heart monitoring, etc. |
| LF | 30–300 kHz | 10-1 km 6.2-0.6 miles |
Guided between the Earth and the ionosphere and ground waves propagation. In Europe and some parts of Asia, the LF band is used in AM broadcasting. Other LF band applications include RFID, amateur radio, and navigation. |
| MF | 300–3000 kHz | 1000-100 m 3,280-328 feet |
Ground waves propagation and slight ionospheric refraction. This frequency band covers AM broadcasting, coast-to-sea communication, emergency distress signals, etc. |
| HF | 3–30 MHz | 100-10 m 328-32 feet |
Ionospheric refraction. This band is also called the short wave band. It is most useful in aviation communication, amateur radio communication, and weather broadcasting applications. |
| VHF | 30–300 MHz | 10-1 m 32-3.2 feet |
* Line-of-sight propagation. This band is used for analog television broadcasting, FM radio broadcasting, medical equipment utilizing magnetic resonance imaging, mobile-land, and marine communication systems. |
| UHF | 300–3000 MHz | 100-10 cm 39-3.9 inches |
* Line-of-sight propagation. This frequency band is significant in modern wireless communication systems with applications in satellite television, WiFi, GPS, Bluetooth, television broadcasting, mobile communications such as GSM, CDMA, and LTE services. |
| SHF | 3–30 GHz | 10-1 cm 3.9-0.39 inches |
* Line-of-sight propagation. Modern communications technologies, modern radars, DTH services, 5GHz Wi-Fi channel, radio astronomy, mobile networks, TV broadcasting satellites, microwave devices, broadcasting satellites, and amateur radio are some of the applications of SHF. |
| EHF | 30–300 GHz | 10-1 mm 0.39-0.039 inches |
** Line-of-sight propagation, limited by atmospheric absorption to a few kilometers (miles). EHF is used in radio astronomy, amateur radio, remote sensing at microwave frequency, and high-frequency microwave relays. |
| THF | 0.3–3 THz | 1-0.1 mm 0.039-0.0039 inches |
** Line-of-sight propagation, limited by atmospheric absorption to a few meters. THF is utilized as an alternative to X-ray and is used in TeraHertz frequency imaging. Other applications include terahertz space-time spectroscopy, solid-state physics, and terahertz computability. |
* Line-of-sight propagation means the wave is not expected to be able to follow a curve nor propagate around and behind objects such as mountains.
** Limited by atmospheric absorption means the radio wave will not bounce off the atmos back down to the surface.
