Where has the passive radar code gone?

I’m in the same industry, and find these attempts of constraining technology through secrecy extremely naive by our legislators. I’d wager that if you already know how to operate an SDR, you properly will have little trouble with the fairly simple algorithm of measuring phase differences, filtering, CFAR etc. to make a passive radar. Synchronizing a bag of RTL-SDRs with a common oscillator is a trivial soldering task.<p>The cat went out of the bag the second SDRs jumped from DARPA R&amp;D to DVB-T commodity.<p>That aside having a passive radar breadboard is not the same as a high-end passive radar where frequency&#x2F;phase stability, use of wideband multi-source emitters, ultra-low noise amplifiers and N&gt;&gt;2 channels for increased angular resolution are integrated in an operational system. These systems that actually works, should be controlled.

You can order a reasonably good passive radar on Alibaba right now.[1]<p><i>The DVB-T&#x2F;T2 Passive Radar (external radiation source radar) itself does not emit signals, but receives the echo signals of non-cooperative radiation sources (radio, television, communication base stations, etc.) reflected by the target for detection (as shown in Figure 1). The radar is composed of antenna, multi-channel receiver, and signal processor: the dedicated reference antenna receives direct wave signals, and the monitoring antenna array receives target echo signals; the multi-channel receiver amplifies the signals received by all antennas, performing frequency conversion and A&#x2F;D sampling. The signal processor processes the output signal of the receiver, and outputs target information after reference signal purification, clutter suppression interference, matched filtering, target detection, parameter estimation and tracking processing. Unlike other passive detection systems, DVB-T&#x2F;T2 Based Passive Radar(external radiation source radar) can achieve single-station positioning and speed measurement, and can detect more types of targets (can detect radio silence targets, such as autonomous cruise drones, birds and balloons), and is particularly suitable for applications where there are restrictions on electromagnetic radiation and high detection performance requirements.</i><p><i>Type of Target: Low-altitude targets such as drones, balloons, paragliders, and general aviation aircraft, including non-cooperative targets with radio silence</i><p><i>Detection Range Directional model: 5 to 10km (DJI Phantom 4), Omnidirectional model: 2 to 4km (DJI Phantom 4)</i><p>All suppressing this does is cut the US out of the market.<p>[1] <a href="https:&#x2F;&#x2F;www.alibaba.com&#x2F;product-detail&#x2F;Silent-Sentry-Passive-Radar_1600484445946.html" rel="nofollow">https:&#x2F;&#x2F;www.alibaba.com&#x2F;product-detail&#x2F;Silent-Sentry-Passive...</a>

Is there overlap between these ITAR restrictions and mmWave radar coming to consumer Wi-Fi routers via IEEE 802.11bf in Wi-Fi 7 (2024)? There are open-source projects which demonstrate Wi-Fi Sensing on $20 Wi-Fi devices, no SDR needed, plus a handful of commercial products with Wi-Fi &quot;motion detection&quot;. There are also several hundred public academic papers on the subject. <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=31561338#31563572" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=31561338#31563572</a><p>Edit1: is Wi-Fi (2.4Ghz+) radar excluded, due to limited range?<p><i>&gt; (xxvii) Bi-static&#x2F;multi-static radar that exploits greater than 125 kHz bandwidth and is lower than 2 GHz center frequency to passively detect or track using radio frequency (RF) transmissions (e.g., commercial radio, television stations); <a href="https:&#x2F;&#x2F;www.ecfr.gov&#x2F;current&#x2F;title-22&#x2F;chapter-I&#x2F;subchapter-M&#x2F;part-121" rel="nofollow">https:&#x2F;&#x2F;www.ecfr.gov&#x2F;current&#x2F;title-22&#x2F;chapter-I&#x2F;subchapter-M...</a></i><p>Edit2: 2.4Ghz Wi-Fi can &quot;see&quot; reflections from moving objects through walls and other physical obstructions, at distances much greater than 0.2m from the obstruction.<p><i>&gt; (xvi) Radar that detects a moving object through a physical obstruction at distance greater than 0.2 m from the obstruction;</i>

I can&#x27;t help but think that the regulators have just triggered the Streisand effect in this case. The components cost for this type of system has sunk through the floor. As in the case of PGP, I suspect that development outside of the US will take place, and we&#x27;ll end up having to &quot;import&quot; the very technology from &quot;experts&quot; outside of the US while the internal pool of experts move on to other less forbidden fruit. Thus we&#x27;ll lose any leadership we had her in the US.

<a href="https:&#x2F;&#x2F;github.com&#x2F;mfkiwl&#x2F;krakensdr_pr" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;mfkiwl&#x2F;krakensdr_pr</a>

Combine this with news about how quickly Starlink mitigated Russian EW and the Pentagon&#x27;s reaction(1). It looks like portions of the US Government have badly underestimated what people and organizations outside their circles can accomplish. It&#x27;s no surprise that their regulations aren&#x27;t keeping up with how the open source SDR community has driven down the barrier to entry.<p>1: <a href="https:&#x2F;&#x2F;breakingdefense.com&#x2F;2022&#x2F;04&#x2F;spacex-beating-russian-jamming-attack-was-eyewatering-dod-official&#x2F;" rel="nofollow">https:&#x2F;&#x2F;breakingdefense.com&#x2F;2022&#x2F;04&#x2F;spacex-beating-russian-j...</a>

&gt; KrakenRF notes that if you must use an FM signal, pick a heavy-metal station “since heavy metal is closer to white noise.”<p>Does a white noise correlation analysis exist for other musical genres?

Explanation of the software and hardware setup: <a href="https:&#x2F;&#x2F;spectrum.ieee.org&#x2F;passive-radar-with-sdr" rel="nofollow">https:&#x2F;&#x2F;spectrum.ieee.org&#x2F;passive-radar-with-sdr</a>

Here&#x27;s another arbitrary passive radar project I just found on GitHub:<p><a href="https:&#x2F;&#x2F;github.com&#x2F;Max-Manning&#x2F;passiveRadar" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;Max-Manning&#x2F;passiveRadar</a><p>I suspect this particular cat is out of the bag.

Does anyone know what regulatory &#x2F; legal hurdles they may be facing? Relevant Wikipedia article [0] is strangely silent on the topic, though my guess would be, this might be classified as military technology.<p>--<p>[0] - <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Passive_radar" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Passive_radar</a>

They could always print it on a T-Shirt, sing it (70&#x27;s folk protest song style), or print it out in book form, then mail it overseas to be OCR&#x27;ed.<p>Those strategies worked for RSA. Anyone have a link to the RSA song? Here&#x27;s a link to the T-Shirt design:<p><a href="http:&#x2F;&#x2F;www.cypherspace.org&#x2F;adam&#x2F;shirt&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.cypherspace.org&#x2F;adam&#x2F;shirt&#x2F;</a>

A procedural victim. Unfortunate, I was hoping to use this to track vehicle speeds on my street.<p>ITAR always falls apart at the edges. High-end thermal and night vision equipment online to “US persons,” but a a bad passive radar’s code isn’t.

The code should just &quot;accidentally&quot; leak somewhere. I bet there are lots of people outside of the U.S. who would subsequenty host it.

Why are developers still limiting themselves by posting their code on the clearweb in a manner they can be traced and held liable for? Host everything on Tor from a server outside USA jurisdiction and this should be a total non issue. Code is speech. It’s time to stop letting the government get away with trampling on our 1st amendment rights to free speech.

How accurate is this? What are some potential use cases?

For those who were looking a link from the forum to the homepage:<p><a href="https:&#x2F;&#x2F;Krakenrf.com" rel="nofollow">https:&#x2F;&#x2F;Krakenrf.com</a>

I wonder what the normal or non-military use cases of this code could be? Planespotting? Indoor navigation?

Here&#x27;s a failed patent on a system to auto-tune an antenna array meant for a KerberosSDR, but easily extendable to a KrackenSDR.<p><a href="https:&#x2F;&#x2F;gitlab.com&#x2F;crankylinuxuser&#x2F;pantograph-antenna-array" rel="nofollow">https:&#x2F;&#x2F;gitlab.com&#x2F;crankylinuxuser&#x2F;pantograph-antenna-array</a><p>All the details are here to do autotuning to the frequencies available to a KrackenSDR dependent on frequencies. This device and antenna go from 400MHz to 1.7GHz.

What was it?

What algorithm was it using? GCC-PHAT?

Anyone has the code pls?

Who are the users of KrakenRF?

what jurisdiction is this in<p>disclaimer, i&#x27;m not related to krakenrf