OnAirDecode Inmarsat (all carriers) with an SDR
Inmarsat: all Aero P and Inmarsat-C carriers at once, needs an L-band antenna and a wide radio (needs a user test).
- In the mode list
- all carriers, L-band
What Inmarsat (all carriers) is
Every Inmarsat L-band carrier in one wide capture, decoded at the same time: Aero P channels (600, 1200 and 10500 bit/s, ACARS and ADS-C with an aircraft map) and Inmarsat-C (EGC safety and news broadcasts), found and listed automatically with a CPU budget. Aero C voice channels are listed but not decoded yet, and voice needs the AMBE codec you install yourself (never shipped). Best with a radio….
Frequencies and settings
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 all carriers, L-band.
What OnAir shows
Every Inmarsat L-band carrier in one wide capture, decoded at the same time: Aero P channels (600, 1200 and 10500 bit/s, ACARS and ADS-C with an aircraft map) and Inmarsat-C (EGC safety and news broadcasts), found and listed automatically with a CPU budget. Aero C voice channels are listed but not decoded yet, and voice needs the AMBE codec you install yourself (never shipped). Best with a radio that does 6 Msps or more (Airspy, SDRplay, HackRF); an RTL-SDR at 2.4 Msps covers one P group. Synthetic signals only so far: needs a user test with a real capture.
Limits and what it was checked with
Checked with generated signals and impairments; recordings of real signals welcome.
Which radio you need
Any radio that tunes this range works. An RTL-SDR covers roughly 24 MHz to 1.7 GHz, and every other radio in the radio guide reaches it too. Antenna height and a clear view of the transmitter matter most.
Receiving and the law
Questions about Inmarsat (all carriers)
Can I decode Inmarsat (all carriers) with an RTL-SDR?
Usually yes for narrowband signals, as 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.
Is it legal to receive Inmarsat (all carriers)?
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 Inmarsat (all carriers) 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.