Kraken

3 Articles

The KrakenSDR in its metal case, with five small antennas connected to it

Open-Source Passive Radar Taken Down For Regulatory Reasons

November 19, 2022 by 92 Comments

Open-source technology brings a world that laws and regulations are not quite prepared for. As a result, every now and then, open projects need to work around governmental regulations. In today’s news, KrakenRF team has stumbled into an arms-trafficing legal roadblock for their KrakenSDR-based passive radar code, and is currently figuring it out. There’s no indication that there’s been any legal action from the USA government – the team’s being proactive, as fas as we’re told.

KrakenSDR hardware, to simplify it a lot, is five RTL-SDRs on one PCB – with plenty of work put in to do it the right way. It gets you much further than a few dongles – there’s shielded case, suitable connectors, reliable power distribution, a proper USB hub, and importantly, receiver synchronization hardware. Naturally, there’s nice things you can build with such a hefty package – one of them is passive radar, which was a prominent selling point on both KrakenSDR’s pre-launch page back in 2021, and on their crowdfunding page just a week ago. How does that work?

There’s RF emissions floating around you in the air, unless you’re at sea or in the desert. Whether it’s airplane transponders, cell towers, or a crappy switch-mode PSU, the radiowaves emitted interact with objects all around you. If you have multiple receivers with directional antennas, you can catch waves being reflected from some object, compare the wave reflected wave to the wave received from the initial source, and determine the object’s properties like location and speed. If you’d like to know more, IEEE Spectrum has covered this topic just a week ago, and the previously-deleted KrakenSDR wiki page has more details for you to learn from.

Through exposure in IEEE Spectrum, the KrakenSDR work has received plenty of attention and comments. And this is where the International Traffic in Arms Regulations (ITAR) laws come in. We’re not lawyers, but it does look like passive radar is on the list. Today, the code repository and the documentation pages are scrubbed clean while the team is talking to legal experts.

Dealing with this is intimidating, and we wish them luck in clearing this with legal. In the bad old days, certain encryption algorithms were famously in scope, which appeared absolutely ridiculous to us at the time. The laws did eventually change to better reflect reality, but the wheels of justice turn slowly.

GSM Sniffing On A Budget With Multi-RTL

January 30, 2017 by 26 Comments

If you want to eavesdrop on GSM phone conversations or data, it pays to have deep pockets, because you’re going to need to listen to a wide frequency range. Or, you can just use two cheap RTL-SDR units and some clever syncing software. [Piotr Krysik] presented his work on budget GSM hacking at Camp++ in August 2016, and the video of the presentation just came online now (embedded below). The punchline is a method of listening to both the uplink and downlink channels for a pittance.

[Piotr] knows his GSM phone tech, studying it by day and hacking on a GnuRadio GSM decoder by night. His presentation bears this out, and is a great overview of GSM hacking from 2007 to the present. The impetus for Multi-RTL comes out of this work as well. Although it was possible to hack into a cheap phone or use a single RTL-SDR to receive GSM signals, eavesdropping on both the uplink and downlink channels was still out of reach, because it required more bandwidth than the cheap RTL-SDR had. More like the bandwidth of two cheap RTL-SDR modules.

Getting two RTL-SDR modules to operate in phase is as easy as desoldering a crystal from one and slaving it to the other. Aligning the two absolutely in time required a very sweet hack. It turns out that the absolute timing is retained after a frequency switch, so both RTL-SDRs switch to the same channel, lock together on a single signal, and then switch back off, one to the uplink frequency and the other to the downlink. Multi-RTL is a GnuRadio source that takes care of this for you. Bam! Hundreds or thousands of dollar’s worth of gear replaced by commodity hardware you can buy anywhere for less than a fancy dinner. That’s a great hack, and a great presentation.
Continue reading “GSM Sniffing On A Budget With Multi-RTL” →

“Strong Enough To Lift A Person, Yet Gentle Enough To Embrace A Child.”

November 28, 2010 by 13 Comments

Tentacles have inspired fear and respect in humans long before anime came into the scene. Sailors shivered in their timbers at the thought of the great Kraken, or that octopus from 20,000 Leagues Under the Sea. It’s no surprise to know that humans have been trying to harness this fear and respect in technological form since the mid-20th century at least.

The fascinating world of tentacle robots has come a long way. It used to be that every breakthrough in tentaclebot technology had to be justified with either a military or misogynistic application, as demonstrated in this remarkable MIT project from 1968.

Thankfully our society has moved on since those misguided times, and while there is still the ever-present military-industrial complex to push for tentacled combat-omatons, forward-thinking people on the domestic front like [festo] demonstrate that at least some of us want to use tentacle robots for peace, love and food handling.

Catch the video after the break.

 

Continue reading ““Strong Enough To Lift A Person, Yet Gentle Enough To Embrace A Child.”” →