Mode UAT

UAT 978 MHz: ADS-B, FIS-B weather and TIS-B relay.

Group	Aviation
Default frequency	978 MHz
Default sample rate	2 Msps
In the mode list	Aircraft, 978 MHz

Step-by-step: Tutorial-UAT

What UAT is

UAT (Universal Access Transceiver) is the 978 MHz ADS-B link used by low-flying aircraft in the United States. Besides ADS-B reports it carries FIS-B weather products and the TIS-B traffic relay (RTCA DO-282).

Frequencies and settings

Setting	Value
Start frequency	978 MHz
Tuning range of the mode table	960 to 990 MHz
Sample rate asked	2 Msps
Lowest working rate	1.9 Msps
Channel width	1 MHz

OnAir takes any frequency you type; the numbers above are the mode's starting point and the range its table describes. In the app the shortcut label is Aircraft, 978 MHz.

What OnAir shows

UAT on 978 MHz: ADS-B position and identity reports, FIS-B weather text products and TIS-B traffic relay (DO-282). Typical 1 Msps capture. Receive only.

Tips and caveats

• Checked with generated signals and impairments; recordings of real signals welcome.
• Which radio: Usually yes for narrowband signals: an RTL-SDR tunes roughly 24 MHz to 1.7 GHz at up to about 2.4 Msps. Wide signals such as TV channels need a faster radio, and OnAir says next to the source what the selected radio can do.
• Try it without a radio: most modes include a built-in synthetic test signal, so you can open the screen and try the controls first.
• Receiving and the law: Receiving aircraft broadcasts is legal in many countries, but some restrict listening to or using what you hear. OnAir is a receiver. Check the rules where you live. See Legal.

Related pages

• All modes, Aviation
• Supported radios, Troubleshooting, FAQ
• More in Aviation: ADS-B, Mode S uplink, ACARS, VDL2, VDL4, HFDL, Airband, VOR, ILS, NDB, Drone Remote ID, FLARM, DJI drones