ADS-B
From The RadioReference Wiki
ADS-B stands for Automatic Dependent Surveillance - Broadcast
You can find some excellent descriptions of the system here:
There are several professional ADS-B receivers on the market for use by pilots and commercial enterprises, too many to list here. This article will try to cover amateur-level ADS-B reception and decoding solutions.
PC-based Decoding Software
ADSB# Free
RTL1090 Free
PlanePlotter Paid
Hardware Decoders
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