Category: Airband

Receiving VOR Radio Navigation with an RTL-SDR and GNU Radio

Over on YouTube user hpux735 has uploaded a video where he explores the feasibility of receiving VOR radio navigation signals using GNU Radio and an RTL-SDR. VOR is an acronym for VHF Omni Directional Radio Range and is an older method of navigation used by aircraft which is quickly being made redundant due to GPS navigation. VOR uses two signals, one master omnidirectional signal and one rotating directional signal. By doing some calculations on the received phase of these two signals it is possible to determine the angle of the aircraft from the transmitter.

In the video hpux735 explains and discusses the VOR signal and also shows how to use these signals for navigation with an RTL-SDR and GNU Radio flowchart. To receive the VOR signal he uses an RTL-SDR to record the VOR signal while he drives around with a car. Then later he uses his GNU Radio program to generate a plot that shows when he is moving and in which direction.

hpux735 has also uploaded some supplemental material over on his blog. In the future he hopes to correlate his VOR results with GPS coordinates that he will take whilst actually flying around.

VORs and SDRs part 1: Playing with angles

Recording Video of Passing Aircraft with A Raspberry Pi and RTL-SDR

Electronics experimenter Simon Aubury has recently made a write up on his blog about a project he has been working on. His project is the use of a Raspberry Pi with servo mounted video camera and RTL-SDR to automatically track and record video of passing aircraft.

Simon’s project works by using the RTL-SDR connected to the Raspberry Pi as an ADS-B receiver. From the ADS-B signals the current coordinates of nearby aircraft can be determined. Then by using some coordinate math, the Raspberry Pi can be told to point its camera in the direction of the aircraft. As well as videoing the passing aircraft, the Raspberry Pi also overlays text on to the video showing information such as flight number, source and destination airports, aircraft type, elevation and distance and date of observation.

In addition to all that, his software also automatically uploads the recorded videos onto his website. Here you can see the latest and closest video captures his system has performed.

[Discovered on Hackaday]

Raspberry Pi RTL-SDR Plane Tracker Video Capture
Raspberry Pi RTL-SDR Plane Tracker Video Capture
Pi Plane Tracking

Hak5: Mobile SDR Apps

On this episode of Hak5, a popular YouTube technology channel, Shannon shows two Android based ADS-B RTL-SDR apps that we have mentioned on this blog previously. One is “ADS-B on USB SDR RTL” and the other is Avare ADS-B. Both are ADS-B apps that will display real time airplane positions on a map.

To run these apps you need a RTL-SDR dongle, a USB OTG cable and an Android phone.

Cellular Testing Tools and Mobile SDR Apps, Hak5 1708

Visualizing ADS-B Data in 3D using MATLAB

Over on Reddit user JorgeGT has posted an animated 3D visualization of his local ADS-B air traffic data using a MATLAB script he wrote. The script collects data from a dump1090 server. If you have a copy of MATLAB, his code can be downloaded from Github here. To run the code JorgeGT writes that you’ll need to do the following.

  • Get dump1090 running on an accessible server: http://url:8080.
  • Get countries/states/provinces SHPs from Natural Earth if you want them to show them and store them in a folder called 10m_cultural.
  • Have a look at my MATLAB script and try to run it.
MATLAB Visualization of ADS-B Data
MATLAB Visualization of ADS-B Air Traffic Data

ADS-B Front-End with LNA and SAW Filter for Improved Reception

Japanese blogger and RTL-SDR experimenter ttreftech has had an ADS-B front end kit (In Japanese, use Google Translate) consisting of a low noise amplifier (LNA) and SAW filter available for sale in Japan for a few months now. The LNA helps to push weak signals through the coax feed line and the SAW filter is a bandpass filter that helps to remove interference outside of the 1090 MHz ADS-B region. If you are interested in building your own version, ttrftech has also posted a schematic. Another recent post about the front-end can be found here.

Another Japanese blogger, “pup” has posted about his results with the ADS-B front end kit (Also in Japanese, use Google Translate). His results show that the front end does significantly improve ADS-B reception. The image below shows an ADS-B signal with the front end turned off (top) and with it turned on (bottom). Pup has also posted a video showing the kit and its performance on HDSDR.

Japanese ADS-B Front End
Japanese ADS-B Front End
ADS-B AMPキットの実験

Using dump1090 in Windows

Dump1090 is a command line based ADS-B decoder for the RTL-SDR. It is considered by many to be the best ADS-B decoder for the RTL-SDR available at the moment. Dump1090 is most commonly used in Linux but over on his blog, SonicGoose has written a tutorial that shows how to use dump1090 on Windows with the popular PlanePlotter software. He also shows how to use ModeSMixer2, which is another command line utility that is used to combine data from multiple ADS-B decoders and then rebroadcast the combined feed.

SonicGoose writes that the reason that many PlanePlotter users are moving away from the simpler GUI based RTL1090 ADS-B decoder is because dump1090 provides better raw data to use for multilateration. Multilateration is a technique supported by PlanePlotter which used data shared from multiple receivers to determine the location of an aircraft, even if that aircraft is not transmitting location information.

Dump1090 Running on Windows
Dump1090 Running on Windows

New RTL-SDR ADS-B App for Android

Over on the Google Play store there is a new (released July 2014) RTL-SDR ADS-B Android app available for purchase called “ADS-B Receiver”. This app allows you to with the aid of an RTL-SDR and USB OTG cable, display live aircraft ADS-B data on your Android phone. This app can also be used to display the live ADS-B data in another app called “Avare”, which provides offline FAA aviation charts and other pilot tools on a Android phone.

The app can be downloaded as a trial version with a fixed limit on the number of packets allowed to be received, or the pro version for around $1.99 USD with no limits.

Previously on this blog we mentioned another similar RTL-SDR Android ADS-B app called “ADS-B on USB SDR RTL“.

ADS-B Receiver on Android
ADS-B Receiver on Android

Monitoring Military Aircraft with an RTL-SDR Part 2

Last month we posted about monitoring and logging military ADS-B data on It turns out that there is another service at that also does military ADS-B logging. One user of has recently uploaded a tutorial showing how to use a RTL-SDR to contribute to their logs. By contributing to their service you get a username and password to access members only sections of their site.

Contribution involves running an ADS-B decoder like RTL1090, sending the decoded data to Virtual Radar Server (VRS) and then using VRS to rebroadcast the data to their Mode-S Logger software.

Some Military ADS-B Logs
Some Military ADS-B Logs

Monitoring Military Aircraft with an RTL-SDR

The military air communications monitoring enthusiasts over at have been using a system involving RTL-SDRs to monitor military air traffic through ADS-B. While military aircraft generally do not transmit GPS position information like commercial aircraft do, they are still able to record live information such as the aircraft’s hex code, registration number, aircraft type, the base station location and a graph of recorded altitudes. They also log all this data showing where military aircraft have been spotted over time.

To receive this information they so far have a network of about 30 volunteers running RTL-SDR based ground stations that use their custom MilAirComms1090 software. If you want to contribute, the software is available for Windows and for Linux/Raspberry Pi.

Example of a US Coast Guard C-130 Aircraft doing Touch/Goes and Sighting History
Example Logs of a US Coast Guard C-130 Aircraft doing Touch/Goes and its Sighting History

FlightAware Introduces PiAware for use with RTL-SDR and dump1090 on a Raspberry Pi

FlightAware is an online service providing real time flight tracking. The flights are primarily tracked by volunteers who run ADS-B decoding hardware which is networked through the internet to the FlightAware servers.

Now FlightAware have written in to to let us know about their new PiAware software which enables a Raspberry Pi running dump1090 to contribute data to the FlightAware network. Dump1090 is a popular RTL-SDR compatible ADS-B decoder program for Linux systems.

A major perk for running their software and contributing data is that FlightAware will buy you a licensed copy of PlanePlotter.

The press release provided is quoted below.

If you are running an inexpensive Raspberry Pi ADS-B receiver with dump1090 then you can install the PiAware Package from FlightAware to freely view nearby flight traffic and transmit this data to FlightAware’s tracking network.  Most aircraft within Europe by 2017 and USA by 2020 will be required to have ADS-B transmitters onboard.
FlightAware’s user-hosted worldwide ADS-B receiver network tracks about 90,000 unique aircraft per day and feeds this live data into the FlightAware website in combination with other public/private flight tracking data sources.  FlightAware has over 500 user-hosted ADS-B sites online across 60 countries, with top contributors tracking over 10,000 aircraft per day.  To see how ADS-B data is put to use, check out the FlightAware Live Map.
The PiAware installation process takes only a few minutes.  If you don’t have PlanePlotter, you can download it and then send FlightAware your installation’s serial number and we’ll buy you a license.  FlightAware will also give users a free Enterprise Account ($90/month value) in return for installing PiAware.
FlightAware Real Time Map Example