ChannelSPURIOUS EMISSIONS
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Episode 1 · ADS-B · Series 01: The Listening Station

How do I see aircraft?

A frame from the draft of episode 1, ADS-B
Release
Length
3:09
On the dial
1090 MHz
Signal
ADS-B

What it covers

Almost every airliner broadcasts its position twice a second on 1090 MHz, unencrypted. In this video I explain how ADS-B works, from the radio pulses to the 112 bits of a message, and how my own receiver decodes it and shares it with nine tracking networks.

The written guide: set this up yourself

Chapters

  1. 0:00Intro
  2. 0:18The broadcast
  3. 0:35The signal
  4. 1:00My receiver
  5. 1:28The message
  6. 2:00My station
  7. 2:41The result

Frames from the draft

ADS-B: Intro
01 Intro
ADS-B: The broadcast
02 The broadcast
ADS-B: The signal
03 The signal
ADS-B: My receiver
04 My receiver
ADS-B: The message
05 The message
ADS-B: My station
06 My station
ADS-B: The result
07 The result

Gear in this episode

FlightAware 1090 MHz fiberglass antennathe antenna on my roof for aircraft
FlightAware Pro Stick Plusthe USB radio I use for ADS-B, with a built-in amplifier and filter
Awxlumv aluminum heat sinks, 50 x 25 x 10 mm (2 pack)the heat sinks I add to most of my SDR dongles (not part of the radios as sold)
Raspberry Pi 4the small computer that runs my ADS-B receiver
ZimaBladethe small server I call Michelangelo
Low-loss coax, N plug to SMA plugthe cable from the aircraft antenna to the radio
CyberPower CP1500PFCLCD UPS (1500 VA, sine wave)the battery backup that keeps almost all of my station running through a power cut

Software and references

dump1090-fagithub.comthe decoder (FlightAware's version of dump1090)
PiAwareflightaware.comFlightAware's ready-made receiver software for a Raspberry Pi
docker-adsb-ultrafeedergithub.comthe hub that reads one stream and feeds many networks
readsbgithub.comthe decoder and data hub inside ultrafeeder
tar1090github.comthe live map
docker-planefencegithub.complanefence and plane-alert: the watcher for unusual aircraft
The 1090 Megahertz Riddlemode-s.orgthe best free book on decoding Mode S and ADS-B, by Junzi Sun

What is simplified, and what is invented

  • The example message is rebuilt from the real callsign and address of a flight my station tracked, with a valid checksum.
  • The line-of-sight drawing is not to scale.