Tagged: radio direction finding

KrakenSDR Update: New Prototypes, Software Updates, Campaign to Release Soon

KrakenSDR is our 5-tuner coherent software defined radio based on RTL-SDR. It is the successor to the KerberosSDR and will be crowdfunded on Crowd Supply with the campaign due to begin soon. Please sign up to the KrakenSDR Crowd Supply mailing list to be notified as soon as the campaign begins, and to check out our previous videos demonstrating the unit in action.

With a 5-channel phase coherent RTL-SDR interesting applications like radio direction finding (RDF), passive radar and beam forming become possible. It can also be used as five separate RTL-SDRs for multichannel monitoring.

KrakenSDR Updates

Like many other projects we have been severely delayed by COVID work restrictions and the effects it's having on the supply chain, and I'd like to thank everyone who is keen to get a hold of a KrakenSDR for their patience. But the ball is rolling faster now and we have finally received our latest KrakenSDR prototypes! Testing has been ongoing for the last few days, and apart from a few minor issues everything is working brilliantly. At this stage we are confident in the design and are making plans to begin the crowdfunding campaign soon.

The latest KrakenSDR Prototype PCB running on a Pi 4.

Supply Chain Constraints

The first batch will unfortunately be limited to 1000 units maximum due to supply constraints and we expect this first batch to be ready 2-3 months after the campaign finishes. So if you are after a unit ASAP, please ensure you are on the CrowdSupply mailing list as we fully expect demand for the first batch to outstrip the supply.

But if you are willing to wait, batch 2 will be still be available at the campaign special price. we will have a second batch available for early preorder at a discount (sorry due to higher than expected shipping and skyrocketing component prices we can't discount the second batch at the moment). Please keep in mind that the second batch will be at least 6 months away due to the long supply chain resulting from the pandemic.

Next Steps

The next stages in hardware development will involve finalizing our custom milled aluminum enclosure, testing one last prototype, and beginning mass manufacturing when the crowd funding campaign is over.

Work on the software is ongoing, but the beta version of our new DAQ firmware and direction finding DSP software layer is stable and already available on the krakensdr GitHub at https://github.com/krakenrf. Everything resides in the development branches and there is full documentation on the code structure available in the Documentation folder. This code can also be used on the KerberosSDR by editing the configuration files to specify 4 receivers instead of 5.

By the time the units ship out we will have a ready to use SD card image for the Raspberry Pi 4 and a quickstart guide available.

KrakenSDR DAQ and DOA DSP Web Interface

Android App

We have also been working at improving the Android direction finding companion app. This app was made during the KerberosSDR release a couple of years ago, and is used to plot and log the direction finding bearings being generated by the Kerberos/KrakenSDR unit, combining it against the GPS and movement data generated by the Android phone. This Android phone + KrakenSDR combination results in a powerful multipath resistant radio direction finding tool, and once enough data has been collected (usually after a few minutes of driving) it is able to determine where the most likely transmitter location is.

The upgraded app makes use of the full 360 degrees of direction of arrival and multipath data that is generated by the KrakenSDR, resulting in a more accurate determination of the transmitter location, and a better understanding of the uncertainties. It also allows users to visualize multipath. There are also various bug fixes and improvements made overall. We are planning to transition this app into a paid app, but all KrakenSDR backers will receive a license for free and the older KerberosSDR app will remain free.

KrakenSDR Android App Improvements

KrakenSDR Antennas

To work as a radio direction finder, KrakenSDR needs five antennas. If you plan to use them in a circular array, they need to be omnidirectional antennas such as whips or dipoles. So to go along with the KrakenSDR we will be selling an optional set of five magnetic whip antennas which can be mounted on for example, the roof of a car. (Please note the magwhips shown in the photo may differ slightly from the final ones sold).

KrakenSDR Magnetic Whips on a Car Roof

We have also been working with Arrow Antennas in the USA, who are producing a KrakenSDR 5-element dipole array antenna which is great for use in fixed sites (for example on the roof of a house). The antenna will be sold by Arrow antennas (not by us), and the future link (not active yet) will be http://www.arrowantennas.com/arrowii/kraken.html. We expect them to generate this page within the next few days. This antenna has been used in all our fixed site experiments as you can see in some of the YouTube videos, and works very well. (The image below show a prototype, we're told the final version may look slightly different.)

Arrow Antenna 5-element antenna array for the KrakenSDR

Future Work

DAQ & Direction of Arrival (DOA / Radio Direction Finding) :
Work on the DAQ and DSP software is coming along well and this is mostly complete and runs stable on a Raspberry Pi 4. There are just now bug fixes and minor features being added. Intermittent 'bursty' signal handing is already working, but we are working on improving it's sensitivity to weak bursty narrowband CW signals which can still be problematic to detect. The Android app is also currently being field tested.

Passive Radar:
Work on new passive radar software is also ongoing and we expect to have something ready for experimentation and with quickstart guides before shipping. At the moment it is also still possible to use the older KerberosSDR software for passive radar, but we believe the new DAQ core software will run things much smoother. The goal for the new software is to not only plot a range-doppler map, but to combine it with direction finding and be able to plot radar detections on a map. This feature may require operation on a device faster than the Raspberry Pi 4, such as GPU based device like a NVIDIA Jetson.

Beam Forming, Interferometry:
One application we think the KrakenSDR would be great with is amateur radio astronomy via interferometry. The ability to combine multiple small hydrogen line dishes spread out over several meters of area should result in much greater radio imaging resolution, without needing to deal with a single huge dish. It may also allow for electrically steering a beam without needing to rotate the dishes.

Advanced Direction Finding + Advanced Log Management:
At the moment networked direction finding (direction finding via multiple fixed or mobile sites spread out around a city or area) is possible via the third party RDF Mapper software, but we aim to create our own advanced platform in the near future. The goal is to have software that will automatically log and alert when a signal of interest appears. For some examples we can see this being used to help coastguard locate distressed marine pleasurecraft that typically do not have AIS via their VHF radios, locate emergency beacons, for animal/wildlife/asset tracking, and monitoring for illegal/interference transmissions.

At this stage the core DAQ+DSP software will also be updated to support monitoring multiple simultaneous channels within the available 2.56 MHz bandwidth, and with a scanning and beacon ID detection feature.

Research into field applications:
One example we hope to test is the operation of KrakenSDR on a drone. With great line of sight from up in the sky, localizing a transmitter should be fast. Another example could be actually visualizing signals like light via augmented reality.

Some of our previous KerberosSDR and KrakenSDR posts might also be of interest.

A KerberosSDR Based Radio Direction Finding RC Boat

If you weren't already aware KerberosSDR is our 4-channel phase coherent capable RTL-SDR unit that we previously crowdfunded back in 2018. With a 4-channel phase coherent RTL-SDR interesting applications like radio direction finding (RDF), passive radar and beam forming become possible. It can also be used as four separate RTL-SDRs for multichannel monitoring.

KerberosSDR is soon to be replaced with the upgraded KrakenSDR, which will begin crowd funding on Crowd Supply later this year. Please note that we have had some pandemic related delays finalizing the design, but progress is being made.

Recently we came across a brief demonstration video on YouTube where it appears that students have embedded a KerberosSDR into an RC boat. The boat carries four direction finding antennas connected to the KerberosSDR and autonomously navigates towards a signal source.

KerberosSDR Direction Finding RC Boat
Kerberos SDR project result

KerberosSDR direction finding #2

DF Aggregator: New Software for Networked Radio Direction Finding with KerberosSDR

Over on GitHub Corey (ckoval7) has released a new open source radio direction program called "DF Aggregator". This software is able to receive bearings and locations from multiple remotely networked KerberosSDRs, and display them on a map.

If you weren't already aware KerberosSDR is our 4-channel phase coherent capable RTL-SDR unit that we previously crowdfunded back in 2018. With a 4-channel phase coherent RTL-SDR interesting applications like radio direction finding (RDF), passive radar and beam forming become possible. It can also be used as four separate RTL-SDRs for multichannel monitoring.

A single KerberosSDR combined with an antenna array is able to determine a bearing towards a signal source. By using multiple KerberosSDR units spread over a large area it is possible to triangulate the location of a transmitter and display it on a map. Corey's software uses a modified branch of our open source KerberosSDR code in order to generate a modified XML page that the mapping software polls for updated data. Some instructions on it's use are available on our forums and on the GitHub.

The image below shows three KerberosSDR stations on the map, and two transmitter locations that have been triangulated using the bearings from the three distributed KerberosSDR units. 

Alternative direction finding mapping software includes our Android App (mostly for mobile vehicular use), and RDF Mapper with our adapter code.

DF Aggregator: KerberosSDR Direction Finding Mapping Software

KerberosSDR Currently On Sale – Ends Midnight Sunday 1 Nov

KerberosSDR is currently on sale for US$150 over on the Othernet store

Sale ends 1 NOV SUNDAY MIDNIGHT (PT)!

If you weren't aware KerberosSDR is our 4-channel phase coherent capable RTL-SDR unit that we previously crowdfunded back in 2018. With a 4-channel phase coherent RTL-SDR interesting applications like radio direction finding (RDF), passive radar and beam forming become possible. It can also be used as 4 separate RTL-SDRs for multichannel monitoring.

In previous posts we've shown some interesting experiments performed with the KerberosSDR. For example:

We note that V2 of our KerberosSDR demo software is also on the way but a little delayed. We are aiming to release a beta around the end of the year, or early next year at the latest. The new software will have better handling of bursty intermittent signals, and paves the way for new developments coming in 2021 such as combined passive radar direction finding.

The KerberosSDR: 4x Tuner Coherent Capable RTL-SDR
The KerberosSDR: 4x Tuner Coherent Capable RTL-SDR
KerberosSDR Android App for Direction Finding
KerberosSDR Android App for Direction Finding
KerberosSDR Passive Radar Display Peak Hold
An Example of KerberosSDR Passive Radar Display Peak Hold Displaying Aircraft and Road Tracks

 

SignalsEverywhere: Driving around with KerberosSDR and Locating a P25 Transmitter

On this weeks episode of SignalsEverywhere, host Corrosive tests out our KerberosSDR coherent RTL-SDR unit for radio direction finding. If you didn't already know KerberosSDR is our experimental 4x Coherent RTL-SDR product. With it, coherent applications like radio direction finding (RDF) and passive radar are possible. Together with the KerberosSDR direction finding Android app it is possible to visualize the direction finding data produced by a KerberosSDR running on a Pi3/Tinkerboard.

In the video Corrosive uses the KerberosSDR together with the recently updated companion Android app to determine the location of a P25 control channel. By driving around with the app constantly collecting data he's able to pinpoint the location within about 15 minutes.

If this interests you, we also have some more driving demo videos available here.

Direction Finding With Kerberos SDR

In addition to his video, Corrosive has also created a very useful calculator that can be used to calculate the required antenna spacing for a circular or linear direction finding array that can be used with the KerberosSDR.

KerberosSDR App Update: Heatmap + Precise TX Localizing & Turn by Turn Navigation Demo Videos

We have just released an updated version of the KerberosSDR Android direction finding app. If you didn't already know KerberosSDR is our experimental 4x Coherent RTL-SDR product. With it, coherent applications like radio direction finding (RDF) and passive radar are possible. Together with the KerberosSDR direction finding Android app it is possible to visualize the direction finding data produced by a KerberosSDR running on a Pi3/Tinkerboard.

The KerberosSDR hardware is currently in preorder status on Indiegogo for the second production batch, and we expect it to be ready to ship out this month. If you preorder then you'll be able to purchase a KerberosSDR at a reduced price of USD$130. After shipping for batch two begins the price will rise to USD$150.

The new version of the KerberosSDR Android app adds the following features:

  1. Heatmap Grid Plotting
  2. Precise TX location pinpointing when enough data points are gathered
  3. Turn by turn navigation to the RDF bearing direction / TX location
  4. Bearing moving average smoothing

To understand what these features are, we've released two demo videos showing them in action. In the first video we use the new features to find an 858 MHz TETRA transmitter, and in the second video we find a 415 MHz DMR transmitter. The first video explains the new features so we recommend watching that first.

KerberosSDR Radio Direction Finding: Heatmap + Auto Navigation to Transmitter Location Demo 1

KerberosSDR Radio Direction Finding: Heatmap + Auto Navigation to Transmitter Location Demo 2

Pseudo-Doppler Direction Finding with a HackRF and Opera Cake

Last week we posted about Micheal Ossmann and Schuyler St. Leger's talk on Pseudo-Doppler direction finding with the HackRF. The talk was streamed live from Schmoocon 18, but there doesn't seem to be an recorded version of the talk available as of yet. However, Hackaday have written up a decent summary of their talk.

In their direction finding experiments they use the 'Opera Cake' add-on board for the HackRF, which is essentially an antenna switcher board. It allows you to connect multiple antennas to it, and choose which antenna you want to listen to. By connecting several of the same type of antennas to the Opera Cake and spacing them out in a square, pseudo-doppler measurements can be taken by quickly switching between each antenna. During the presentation they were able to demonstrate their setup by finding the direction of the microphone used in the talk.

If/when the talk is released for viewing we will be sure to post it on the blog for those who are interested.

OperaCake running with four antennas
OperaCake running with four antennas
Schyler's Poster on Pseudo Doppler from GNU Radio Con 17.
Schyler's Poster on Pseudo Doppler from GNU Radio Con 17.

 

YouTube Talk: Hunting Rogue WiFi Devices using the HackRF SDR

Over on YouTube a video titled “Hunting Rogue WiFi Devices using the HackRF SDR” has been uploaded. The talk is given by Mike Davis at the OWASP (Open Web Application Security Project) Cape Town. The talk’s abstract reads:

Rogue WiFi Access Points are a serious security risk for today’s connected society. Devices such as the Hak5 Pineapple, ESP8266-based ‘throwies’, or someone with the right WiFi card and software can be used to intercept users’ traffic and grab all of their credentials. Finding these rogue devices is a very difficult thing to achieve without specialised equipment. In this talk Mike will discuss the work he has been doing over the past year, to use the HackRF SDR as a RF Direction-finding device, with the goal of hunting down various malicious RF devices, including car remote jammers.

The talk starts off with the basics, explaining what the problems with WiFi devices are, what the HackRF and SDR is, and then goes on to explain some direction finding methods that Mike has been using. 

Hunting rogue WiFi devices using the HackRF SDR - Part 1 of 2

Hunting rogue WiFi devices using the HackRF SDR - Part 2 of 2