2-1190-01122-03 Rev. C Garmin GDL 88 ADS-B Transceiver Pilot’s Guide2 ADS-B SYSTEM OVERVIEWADS-B is a core technology in the FAA Next Gen air traffic control system andis comprised of three segments: ADS-B (Broadcast), ADS-R (Rebroadcast), andTIS-B.Nearly 400 ADS-B ground stations were completed and operational by mid-2012, with most of the rest — totaling more than 700 planned stations —expected to be operational by early 2014. The graphic below illustrates whereADS-B is currently operational. In the areas highlighted in blue, you can alreadystart taking advantage of ADS-B’s datalink traffic and subscription-free weatherservices if you’re equipped with an ADS-B “In” solution.Figure 2-1 ADS-B Ground Stations (mid-2012) - FAA Illustration