Open Source Military TAK Android App Supports RTL-SDR ADS-B Tracking

ATAK (Android Tactical Assault Kit) is an Android app used by some branches of the US military for visualizing geospatial information such as enemy and friendly positions, as well as any other information of interest. The civilian version of ATAK (CivTAK) was recently open sourced in 2020 and can be downloaded from the Google Play Store.

The software has a huge number of features for coordinating teams, planning operations and visualizing information. It can even network via handheld, or ham radios or a Meshtastic LoRa network if a central server and internet connection is unavailable. Of note is that their plugin page references the possibility of using a plugin that uses RTL-SDR hardware for ADS-B aircraft tracking. However, it appears that the plugin needs to be purchased from tak.gov. We suspect that in the future there will be more RTL-SDR compatible plugins available.

[First seen on Hackaday]

ATAK on an Android Device

An Inside Look into FlightAware’s RTL-SDR

Over on the FlightAware blog, Hardware and Software Engineers Eric Tran and Ziquan Wang have put up a blog post showing how they have designed the FlightAware RTL-SDR hardware and software, and detail some future plans.

FlightAware is a company that specializes in distributed ADS-B aggregation, in order to produce real time maps and information about what aircraft are in the air. In 2021 FlightAware was acquired by Collins Aerospace, which is a subsidiary of Raytheon Technologies, a large US aerospace and defense contractor.

Most of the data that FlightAware obtains comes from volunteers all around the world running an RTL-SDR dongles on their Raspberry Pi based image. The dongles receive the ADS-B 1090 MHz broadcasts from aircraft which contain information about the aircraft including GPS location. 

Back in 2016 they released the FlightAware ProStick, which is an ADS-B optimized RTL-SDR with onboard 1090 MHz LNA.  Later in 2017 they released the Prostick Plus which improved performance in high interference areas due to the addition of a 1090 MHz SAW filter.

Their post goes into more detail about their products, and note that they are currently designing a new Prostick Plus with filter placed before the LNA instead of after. They also discuss how they are looking into higher end 12-bit ADCs for their receiver hardware, and at creating a dual channel receiver for the 978 MHz UAT band as well. They then go on to discuss the software architecture behind the ADS-B decoder they use.

FlightAware ADS-B Kitset

KrakenSDR Locates a TETRA Transmitter

Over on YouTube F4IPO has posted a video of him using a KrakenSDR and the KrakenSDR Android mapping app to quickly locate the source of a TETRA transmission at 427 MHz in France.

The KrakenSDR is our 5-channel coherent radio based on RTL-SDRs, and it can be used for applications like radio direction finding and passive radar. We successfully crowd funded the device on Crowd Supply.  

In the video F4IPO shows a dash cam recording of his vehicle alongside a screen recording of his Android phone screen. He makes use of the auto-navigation feature which navigates him right to the radio transmit tower. He notes that the entire process to locate the transmitter only took about 5 minutes. At the end of the video he shows the antenna setup on his roof.

KrakenSDR : recherche d'un émetteur TETRA

IEEE Spectrum: Chasing Weather Balloons with Software Defined Radio

Electrical engineering magazine IEEE Spectrum has recently shared a story about how RTL-SDRs can be used for chasing weather balloons. With an RTL-SDR, antenna and appropriate decoding software, it is possible to decode the telemetry signal from weather balloons radiosondes, and track their live GPS location.

The author, James Provost explains how chasing and hunting weather balloons can be a fun sport. To help with his hunt James uses an RTL-SDR, a directional antenna and the Sondehub Tracker website.

First James logged onto Sondehub Tracker which aggregates multiple weather balloon signals received by volunteer ground stations. One feature of Sondehub is that it can predict an approximate landing position of a balloon. It however cannot track a balloon right to its final landing spot as usually the ground station will loose signal when the balloon gets too low.

Knowing the approximate landing position, James drove out to the indicated location and then took out his RTL-SDR and directional antenna and was able to track and find the radiosonde by decoding the telemetry signal with Sonde Monitor

IEEE Spectrum Weather Balloon hunting graphic

Software Defined Radio Academy 2022 Conference Talks

Videos of talks from the Software Defined Radio Academy 2022 (SDRA22) conference have recently been uploaded to YouTube. SDRA22 was held during the HAMRadio World Fair in Friedrichshafen, Germany during June 2022. The talks include topics on:

  • Usage of SDR in a contest
  • HackRF Supercluster
  • PLLs in software defined radios
  • M17 Project: A new digital voice mode for VHF and up
  • RM Processor to Xilinx FPGA Connection for SDR
  • User-Assisted Spectrum Labeling
  • The perfect HF Receiver. How would it look like today?
  • FutureSDR: An Async SDR Runtime for Heterogeneous Architectures
Playlist: SDR Academy 2022 @HAM Radio Fair

Running KrakenSDR on the Steam Deck

DragonOS creator Aaron has recently put out a few Tweets showing that he has been successful at getting his KrakenSDR to run on a Steam Deck. The Steam Deck is a handheld gaming device made by Valve, the creators of several famous PC games and the Steam game store. It is essentially a powerful handheld computer with screen and good battery life, so it makes an excellent mobile SDR computing platform too.

Aaron notes that the output power of the Steam Desk isn't enough to power the KrakenSDR itself, but after adding an external battery pack it works well.

Frugal Radio KrakenSDR Part 1 – Unboxing, Antennas and Initial Setup

Over on the Frugal Radio YouTube channel Rob has uploaded part one of his two part series on the KrakenSDR. The KrakenSDR is our 5-channel coherent radio based on RTL-SDRs, and it can be used for applications like radio direction finding and passive radar. We successfully crowd funded the device on Crowd Supply.  

In the video Rob unboxes his KrakenSDR, and explains how he will use it for radio direction finding. He shows his setup including the other required parts, like the Pi 4, and power supply, and then goes on to show the software installation process which involves burning an SD card and downloading an Android app. Next he sets up his antenna array by printing the antenna spacer and using the Excel antenna array calculator sheet.

Rob notes that Part 2 is coming in one to two weeks and will show him using the KrakenSDR in his vehicle to locate the source of a transmission.

KrakenSDR Unboxing / Prep & Setup device & antennas : Part 1

SATRAN MK3 Antenna Rotator Hardware Kit Released

Back in January 2021 we posted about the release of the SATRAN product, which is a low cost automatic motorized satellite antenna rotator kit. The rotator is deigned to be used for pointing high gain directional antennas such as a Yagi or satellite dish at low earth orbit satellites which can move across the sky quickly. They also supply an Android App for easily controlling the rotator.

Recently SATRAN MK3 (version 3) has been released a few days ago and costs € 175,00 for the kit, but does not include the plastic parts which need to be 3D printed. Unfortunately the kit appears to already be sold out, but we suspect they are working on getting more kits soon. Also of note is that they are based in Sweden and cannot ship to the US or Canada.

The email announcement reads:

"There's a new Satran in town!"

I'm glad to announce the newest Satran MK3 Rotator which is now available in the shop. The former cast aluminum version has been abandoned since the production was way too time-consuming and expensive.

The new MK3 has taken all the advantages of both older versions and returned to a more open source and 3D-printable design. This cuts the price by two thirds, while still getting a really user-friendly, compact and able device.

...and there's a new app!

Some users have reported issues with their Android app crashing, so today a new version of the app (2.3) has been finished and will be available in a day or two. If you don't get an update notification automatically in your app, visit Google Play to check for the latest version. 

The app also have a more extensive list of satellites and the possibility to search for a satellite by its Norad ID. 

SATRAN MK3 Antenna Rotator
SATRAN MK3 plastic parts that need to be 3D printed.