The classic 1090 MHz Mode S / ADS-B decoder for RTL-SDR. Demodulates the 1 Mbps PPM Extended Squitter, decodes DF17/DF18 frames (ICAO 24-bit address, callsign, position, velocity, altitude) and serves the result over a built-in web map and on Beast/raw/JSON network ports. The maintained dump1090-fa fork is the de-facto reference receiver; pure RX, no transmit.