GSMmobile phones operate at 800–900 and 1800–1900 MHz. Iridium Satellite LLC phones use frequencies between 1616 and 1626.5 MHz to communicate with the satellites. Inmarsat and LightSquared terminals use frequencies between 1525 and 1646.5 MHz to communicate with the satellites. Thuraya satellite phones use frequencies between 1525 and 1661 MHz to communicate with the satellites.
Aircraft can use Automatic dependent surveillance-broadcast (ADS-B) equipment at 1090 MHz to communicate position information to the ground as well as between them for traffic information and avoidance. The 1090 MHz frequency is also used by Mode S transponders, which ADS-B extends when operated at this frequency. ADS-B information can also be broadcast just outside the L band range at 978 MHz.
The band also contains the hyperfine transition of neutral hydrogen (the hydrogen line, 1420 MHz), which is of great astronomical interest as a means of imaging the normally invisible neutral atomic hydrogen in interstellar space. Consequently parts of the L-band are protected radio astronomy allocations worldwide.