FlightAware Discussions

Help with ADS-C / INMARSAT?

Hi all,

Firstly, can we discuss ADS-C here (perhaps in a new sub forum) - does this meet the goals / intentions of FlightAware?

If so, I’d be very interested in discussing and building an ADS-C receiever for use with INMARSAT - from what I’ve read, this uses INMARSAT birds to recieve aircraft positions etc over satellite? Removes the limitation of “radio coverage / distance” , and could perhaps still feed into and meet FA’s plane-plotting goals?

Interesting article here…


**@MODS - please feel free to remove if inappropriate / off topic… **

So - this is very very possible and has indeed been done - however, it’s not for the faint of heart.

The small dish with the little GPS antenna he’s pictured on the site can indeed decode L-Band signals, which are used for the ground-to-aircraft link,

However: the Air-to-Ground link containing the coveted positioning data operates on the C-Band 3600 MHz - 3629 MHz using 10.5 kbps burst packets sent via A-QPSK

What does that mean for you?

Well - decoding these signals with a discarded DirecTV dish and an RTL dongle isn’t going to happen. Here’s the dish he uses:

The link you posted has all the code you’ll need, but to recieve it properly one needs a 3m dish, a PLL LNB, and a pretty high quality SDR. (he’s using an SDRplay)

So, with Time, Space for the Dish itself, and about $400 you too can pick up ADS-C.

I, however, live in an apartment. :smiley:

Some of the members of Planeplotter user Group are already running dishes with Jaero and feeding inmarsat acars positioning data in to the Planeplotter system.

You will find a group of pp members who share their ideas and techniques link below


See this thread also (Created on Mar 09, 2016)

Satellite ACARS (SatCom ACARS)

Thanks for the feedback guys…

@JonHanford - hmmm, the A2G comms like that might have to wait till a future phase… :wink:
(DOnt know how chuffed my GF would be with a 3m dish in the garden :wink: ).

I do, however, understand re the freq range etc of the rtl vs what’s needed.

Thanks for the links gents, I’ll take a read.

1 Like

i’m looking to have a little play with this too, just need to find a dish.

Drive through just about any rural area of any U.S. state. Find a mobile home sitting in the middle of a field. Chances are good that an old C-Band dish is sitting next to it. Make an offer. Beware of dog.


The guys at Planeplotter await their first dish downloaders from the USA or Central Europe to subscribe /set up and begin feeding .
A 1.2mtr or 1.8mtr dish will get signals from Inmarsat/Alphasat service.


The planeplotter group doesn’t seem to provide public archives so linking to it is somewhat pointless…

1 Like



1 Like