Tracking International Flights via Raspberry Pi

This article explains how a Raspberry Pi can be transformed into a local radar station to track international flights using radio signals. By decoding Automatic Dependent Surveillance-Broadcast (ADS-B) signals transmitted from commercial aircraft, a Raspberry Pi paired with a low-cost Software Defined Radio (SDR) receiver can capture real-time aviation data including altitude, speed, and flight coordinates. Readers will discover the required hardware components, the software setup process, and how to visualize or share this live flight data globally.

The Core Technology: ADS-B Signals

Modern commercial aircraft continuously broadcast tracking information using a system called Automatic Dependent Surveillance-Broadcast (ADS-B). This technology relies on an onboard transponder that determines the aircraft’s precise position using satellite navigation systems. The position, alongside vital telemetric data such as flight number, velocity, heading, and altitude, is broadcast unencrypted via radio frequencies at exactly 1090 MHz.

Because these signals are public and unencrypted, anyone with a proper radio antenna and a decoding computer can capture them. A standard ground station can intercept these broadcasts from aircraft up to 250 miles away, provided there is a relatively clear line of sight between the receiver antenna and the open sky.

Required Hardware Components

Building a DIY flight tracker requires a modest amount of hardware, centered around a compact computer and an inexpensive radio receiver.

• Raspberry Pi: A Raspberry Pi 3, 4, 5, or Zero 2 W is ideal. The device processes the raw radio signals decoded by the receiver.
• MicroSD Card: An 8GB or larger card to host the operating system and tracking software.
• USB SDR Receiver: A Software Defined Radio USB dongle based on the RTL2832U chipset. Many specialized dongles come with built-in 1090 MHz amplifiers and filters to reduce background radio noise.
• 1090 MHz Antenna: A small magnetic antenna often comes bundled with the SDR, but a specialized, outdoor-mounted 1090 MHz antenna drastically maximizes range.
• Power Supply and Internet: A stable power adapter for the Pi and a local Wi-Fi or Ethernet connection to update software and share data.

Setting Up the Software

The setup involves flashing specialized software to the Raspberry Pi to control the USB radio dongle and decode the incoming binary pulses into human-readable data.

There are two primary methods to deploy the software:

1. Dedicated OS Images

Major aviation tracking networks like Flightradar24, FlightAware, and ADS-B Exchange offer pre-configured operating system images (such as Pi24 or PiAware). Using a tool like the Raspberry Pi Imager, you flash this custom software directly onto the microSD card. Upon booting the Pi with the USB SDR connected, the system immediately initializes as a dedicated flight-tracking node.

2. Manual Terminal Installation

For users who prefer to use a standard Raspberry Pi OS, the tracking software can be added manually. By accessing the Pi via a secure shell (SSH) or a local terminal window, a user can run a simple installation script provided by the chosen flight service. For instance, installing a tracker client pulls down a foundational decoder application known as dump1090. This program handles the heavy lifting of translating the raw 1090 MHz I/Q radio data samples into structured flight coordinates.

Visualizing and Sharing Flight Data

Once the software is operational, the Raspberry Pi begins logging aircraft data immediately. The dump1090 utility launches a local web server on the Pi. By typing the local IP address of the Raspberry Pi into any web browser on the same network, users can access an interactive, real-time map displaying every aircraft currently being tracked by their antenna. Clicking on an aircraft reveals its flight number, altitude, speed, and visual trajectory.

Beyond personal mapping, users can feed their data streams to global aggregation networks. In exchange for contributing local coverage data, platforms like Flightradar24 and FlightAware reward hosts with premium, data-rich subscription tiers for free. By leveraging Multilateration (MLAT)—a process where multiple ground stations calculate the time-difference-of-arrival of a signal—these networks can even pinpoint older commercial and military aircraft that do not broadcast full GPS data, providing a comprehensive view of global airspace right from a home setup.