More Raspberry Pi Projects

Project 7 — ADS-B Flight Tracker

What Is ADS-B?

Modern commercial aircraft broadcast their position, altitude, speed, and flight number every second using a radio signal called ADS-B (Automatic Dependent Surveillance–Broadcast) on 1090 MHz. This data is used by air traffic control — but it's also transmitted openly and unencrypted, meaning anyone with the right hardware can receive it.

A cheap RTL-SDR USB dongle — originally designed to receive digital TV broadcasts — can receive these 1090 MHz signals. Combined with software running on your Pi, you get a live radar map of every ADS-B-equipped aircraft within roughly 200–300 km of your antenna.

What You Will Need

Step 1 — Install readsb

readsb is a high-performance ADS-B decoder that reads the raw signal from your RTL-SDR dongle and decodes it into structured flight data. It is the successor to the popular dump1090 family and is actively maintained.

# Add the wiedehopf repository (author of readsb and tar1090)
pi@raspberrypi:~$ sudo apt install -y curl gnupg

pi@raspberrypi:~$ curl -L https://github.com/wiedehopf/adsb-wiki/raw/master/readsb-install.sh | sudo bash

If you prefer to install manually:

# Manual install (if the script is unavailable or you prefer step-by-step control)
pi@raspberrypi:~$ sudo apt update
pi@raspberrypi:~$ sudo apt install -y rtl-sdr

# Blacklist the DVB-T driver so it doesn't claim the dongle
pi@raspberrypi:~$ sudo bash -c 'echo "blacklist dvb_usb_rtl28xxu" > /etc/modprobe.d/rtlsdr.conf'

# Add the readsb Debian package repository
pi@raspberrypi:~$ sudo bash -c '(source /etc/os-release; echo "deb [arch=arm64] https://github.com/wiedehopf/readsb-packages/raw/master/apt stable main") > /etc/apt/sources.list.d/readsb.list'

pi@raspberrypi:~$ sudo apt update
pi@raspberrypi:~$ sudo apt install -y readsb

Configure readsb with your location

pi@raspberrypi:~$ sudo nano /etc/default/readsb

Find and set these lines (replace with your actual coordinates and elevation):

RECEIVER="rtlsdr"
DECODER_OPTIONS="--dcfilter --fix"
NET_OPTIONS="--net --net-heartbeat 60 --net-ro-size 1250 --net-ro-interval 0.05 --net-ri-port 0 --net-ro-port 30002 --net-sbs-port 30003 --net-bi-port 30004,30104 --net-bo-port 30005"
JSON_OPTIONS="--json-location-accuracy 2"
LAT=51.5074     # your latitude (positive = North)
LON=-0.1278     # your longitude (negative = West)
ALTITUDE=50     # your elevation in metres above sea level

pi@raspberrypi:~$ sudo systemctl restart readsb
pi@raspberrypi:~$ sudo systemctl status readsb
● readsb.service
     Active: active (running)

Check that the dongle is being detected

pi@raspberrypi:~$ sudo readsb --device-type rtlsdr --device 0 --interactive
Found 1 device(s):
  0:  Realtek, RTL2838UHIDIR, SN: 00000001

Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
Sampling at 2400000 S/s.
...

Step 2 — Verify Data Is Flowing

Before installing the web interface, confirm readsb is actually decoding aircraft:

# readsb writes decoded aircraft to this JSON file every second
pi@raspberrypi:~$ watch -n1 'cat /run/readsb/aircraft.json | python3 -m json.tool | head -40'

Or use the raw data stream directly:

pi@raspberrypi:~$ nc localhost 30003 | head -20
MSG,3,1,1,400F3A,1,,,,,,,36000,,,51.23,-0.41,,,0,0,0,0
MSG,4,1,1,4CA7B6,1,,,,,,449,215,,,,,,,0,0,0
MSG,1,1,1,400F3A,1,,,,,BAW123,,,,,,,,0,0,0,0

If you see output like this, readsb is receiving and decoding ADS-B messages. No output means no aircraft in range yet — try pointing the antenna out of a window, or wait a few minutes.

Step 3 — Install tar1090 (Radar Web Interface)

tar1090 is a polished, feature-rich web interface that reads readsb's JSON output and displays it as an interactive radar map. It's fast, beautiful, and runs entirely locally with no internet connection required for the map itself.

pi@raspberrypi:~$ curl -L https://github.com/wiedehopf/tar1090/raw/master/install.sh | sudo bash

The installer sets up tar1090 to run under a lightweight HTTP server on port 8080. Open it in your browser:

http://raspberrypi.local:8080

Configure tar1090 for your location

pi@raspberrypi:~$ sudo nano /etc/tar1090/config.js

// Centre the map on your location
SiteLat  = 51.5074;
SiteLon  = -0.1278;
SiteShow = true;           // show your location as a dot on the map
SiteName = "My Pi";

// Display preferences
DefaultZoom         = 7;    // map zoom level on load (7 shows a wide regional view)
ShowAltitudeChart   = true;
TrackHistorySize    = 200;  // number of trail points per aircraft
PageName            = "My Flight Radar";

Step 4 — Install graphs1090 (Statistics Dashboard)

graphs1090 generates historical graphs of your station's performance — message rates, aircraft counts, range over time, and signal strength. Install it alongside tar1090:

pi@raspberrypi:~$ curl -L https://github.com/wiedehopf/graphs1090/raw/master/install.sh | sudo bash

Access the graphs dashboard at:

http://raspberrypi.local:8080/graphs1090/

After a day of operation you'll see charts showing when aircraft traffic peaks (morning and evening rushes are clearly visible), your maximum detection range, and how different antenna positions affect your message rate.

Step 5 — Feed Data to FlightAware (Optional)

FlightAware, Flightradar24, ADSBexchange, and others aggregate ADS-B data from volunteer feeders worldwide to build their global flight tracking maps. Sharing your local data earns you a free premium account on most of these services — and it genuinely improves flight tracking coverage in your area.

Install PiAware (FlightAware feeder)

# Add FlightAware's repository
pi@raspberrypi:~$ wget -O /tmp/piaware_bullseye_arm64.deb \
  https://flightaware.com/adsb/piaware/files/packages/raspbian/bullseye/piaware_10.0_arm64.deb
pi@raspberrypi:~$ sudo apt install /tmp/piaware_bullseye_arm64.deb

pi@raspberrypi:~$ sudo piaware-config allow-auto-updates yes
pi@raspberrypi:~$ sudo piaware-config allow-manual-updates yes

pi@raspberrypi:~$ sudo systemctl start piaware
pi@raspberrypi:~$ sudo systemctl enable piaware

Claim your feeder at flightaware.com/adsb/piaware/claim — log in or create a free account and it will automatically detect your running PiAware instance.

Install fr24feed (Flightradar24 feeder)

pi@raspberrypi:~$ wget -O /tmp/fr24feed.deb https://repo-feed.flightradar24.com/linux_arm_binaries/fr24feed_1.0.40-2_armhf.deb
pi@raspberrypi:~$ sudo dpkg -i /tmp/fr24feed.deb

# Run the signup wizard (creates an account and generates your sharing key)
pi@raspberrypi:~$ sudo fr24feed --signup

The signup wizard asks for your email address, location, and MLAT preference. It configures fr24feed to read from readsb's output port automatically.

Step 6 — Improve Your Range

Once everything is working, antenna placement is the single biggest factor in how many aircraft you can see. Here's what makes the biggest difference:

Antenna height

ADS-B signals travel in straight lines (line-of-sight). Every metre of additional antenna height extends your horizon. A loft-mounted antenna will typically see 2–3× more aircraft than one on a windowsill.

Avoid coax cable runs

Standard coax cable loses signal at 1090 MHz — roughly 6–10 dB per 10 metres of RG58. Use low-loss cable (LMR-400 or equivalent) for runs longer than 2 metres, or use a long USB cable and put the Pi near the antenna instead.

Use a bandpass filter

Strong nearby signals (mobile phone masts, FM radio) can overload the RTL-SDR's tuner and mask weak ADS-B signals. A 1090 MHz bandpass filter (~£10) placed between the antenna and dongle dramatically improves performance in urban areas. The FlightAware 1090 MHz dark blue filter is the standard recommendation.

Build a simple DIY antenna

A quarter-wave ground-plane antenna for 1090 MHz is one of the most cost-effective projects in amateur radio. You need one vertical element of 69 mm and four radial ground elements of the same length, made from stiff wire or a coat hanger. Plenty of build guides exist at rtl-sdr.com.

Troubleshooting

Quick Reference