OnAirSatellite & navigation · Experimental
Decode GNSS with an SDR
OnAir receives GNSS. GNSS satellites (GPS, GLONASS, BeiDou, Galileo) around 1575 MHz, needs an active antenna.
What GNSS is
GNSS satellites (GPS, Galileo, GLONASS, BeiDou) broadcast signals from which a receiver works out position and time.
Frequencies and where it is used
GPS L1.
In OnAir the tuning shortcut is GPS, GLONASS, BeiDou; you can enter any frequency your radio reaches.
What OnAir shows for GNSS
Satellites, position and time.
This receiver is built from the published specification and checked end to end on simulated signals. It has had little or no testing on real transmissions yet, so reports and recordings on Discord are welcome.
Which radio you need
This mode sits at a high frequency, so check that your radio tunes it: a HackRF covers 1 MHz to 6 GHz, and RTL-SDR stops near 1.7 GHz. Some modes at these frequencies also need a fast radio (10 to 20 Msps) or a dish and an LNB.
Questions about GNSS
Can I decode GNSS with an RTL-SDR?
Probably not: an RTL-SDR tunes up to about 1.7 GHz. A HackRF (1 MHz to 6 GHz) or another wideband radio is the usual choice for this frequency range.
Is it legal to receive GNSS?
Receiving satellite downlinks is generally legal. Encrypted or spread content is not decoded, and voice codecs that are patented are not shipped with OnAir.
Can I try GNSS in OnAir without a radio?
Yes. Most modes include a built-in synthetic test signal, so you can open the screen and try the controls before you own a radio.
Try it without a radio
OnAir includes built-in synthetic test signals for most modes, so you can open this screen, see the layout and try the controls before you own a radio. The Tour button walks you through the app.