For a long time I have been interested in finding out more about CPDLC. The Controller Pilot Data Link Communications primarily operate via VDL/2 (on VHF) and SATCOM, with a number of comms also happening via HFDL (HF).
I found an active L band patch antenna available for under $15, and figured I would try it out. What fun I had! From my location I was able to receive data on 600, 1200 and 10500bps channels from 2 different satellites.
This antenna also enabled me to receive SATCOM audio from the Inmarsat birds. This might be of particular interest to those interested in Military Airband communications.
JAERO is the software I used in this demonstration.