ADS-B Mode-S

My tracking of nearby ADSB-out aircraft using my local AWACS server.

1090-at-work

Automatic dependent surveillance-broadcast - Mode-S

On January 1, 2020, Federal Regulation 14 CFR § 91.225 requiring ADSB-out to transmit their position information to ATC and other aircraft takes effect. This applies to all aircraft above 10,000 MSL, inside Class A, B, and C airspace, and within 30 NM of a Mode-C airport to the surface. Since the transmission happens at 1090MHz, is vertically polarized, and is receivable within a line of sight, ground stations can pick up signals from aircraft hundreds of nautical miles away flying at high altitude!

Unscientific deployment observation

Being within the KIAH Mode-C ring, all planes are required to have a squawkable transponder for the primary ATC radar. Unfortunately, most of these planes are invisible without the 1090MHz transponder which allows for a MLAT(multi-lateration) calculation with multiple base stations. Sometimes an ADSB-IN aircraft is flying nearby which will activate a ADSB-R (rebroadcast). The traffic within several miles and within 5000' of the aircraft will be rebroadcast meaning that my AWACS system can now see the ground traffic at major airports as well as random signatures for the remainder of the transponder only flights.

Yesterday's Stats

Yesterday's Flights last 24h range Flight and plane information

504 Gateway Time-out

504 Gateway Time-out


nginx/1.27.1

You only need a few things to get started:

My long range setup is using a Raspberry Pi Zero and a ProStickPlus. PiZero + ProStickPlus

To improve the setup:

ADSB-in

Since it's more expensive to add ADSB-in capability and not required by the FAA many planes don't have this. Fortunately, using almost the same setup as my home AWACS system Stratux can supplement your electronic flight bag. I'm currently using Avare with the external i/o plugin to connect to the homebuilt stratux.

References and Software

gr-air-modes - ADS-B receiving software.
wikipedia ADS-B
rtl-sdr ads-b article
antirez dump1090
satsignal pi-1090
asd-b.ca
mutability mlat-server
alkissack dump1090
British Airways used this in a pretty neat marketing campaign #lookup.