This is incredible stuff! One of the less-hyped slow revolution is what's happening in non-wearable sensing. Some of it is driven by the consumer-ization of advanced radar systems, a technology that was the domain of the military and space/satellite comm.<p>Some companions to this work:<p>1. Wifi sensing from academia, particularly in the ubiquitous computing community- Shwetak Patel's group in Washington [1], Dina Katabi's group in MIT [2], Patwari's group in Utah [3], etc.<p>2. MIT OCW on how to build a radar system with advanced [4] capabilities <a href="http://ocw.mit.edu/resources/res-ll-003-build-a-small-radar-system-capable-of-sensing-range-doppler-and-synthetic-aperture-radar-imaging-january-iap-2011/" rel="nofollow">http://ocw.mit.edu/resources/res-ll-003-build-a-small-radar-...</a><p>[1] <a href="https://ubicomplab.cs.washington.edu/" rel="nofollow">https://ubicomplab.cs.washington.edu/</a><p>[2] <a href="http://groups.csail.mit.edu/netmit/wordpress/projects/projects/" rel="nofollow">http://groups.csail.mit.edu/netmit/wordpress/projects/projec...</a><p>[3] <a href="http://span.ece.utah.edu/neal-patwari" rel="nofollow">http://span.ece.utah.edu/neal-patwari</a><p>[4] I use 'advanced' in the sense that it is way, way, more sophisticated in its use of math and signal processing/machine learning/linear algebra algorithms than your standard automotive speed monitoring radar.
Previous discussion of a similar project, by [evidently] the same person: <a href="http://hforsten.com/6-ghz-frequency-modulated-radar.html" rel="nofollow">http://hforsten.com/6-ghz-frequency-modulated-radar.html</a><p>As before, this is totally awesome---until the FCC (or other national spectrum regulator) shows up at your door...<p>Here is an assortment of things that the author might be interfering with in the neighborhood of his 5.5 GHz carrier frequency: <a href="https://wirednot.wordpress.com/2014/01/07/what-else-is-in-the-5-ghz-spectrum-hint-its-not-just-weather-radar/" rel="nofollow">https://wirednot.wordpress.com/2014/01/07/what-else-is-in-th...</a><p>Some of this is the sort of stuff you really don't want to interfere with--both for safety reasons, and because of the likelihood of enforcement.<p>Next time I suggest that the author look into whether his jurisdiction will grant him an experimental license so he can do this legally. In many jurisdictions that is cheap and easy (unless, of course, you want to operate in a band where the interference risk is just too high).<p>Edit: I see the author is in Finland. Unfortunately for the author, I'm guessing this changes nothing since these frequencies are regulated both nationally and internationally. But it does mean that there is probably some local variation in the exact services that might be subject to interference. And who knows: maybe in Finland the 5.5 GHz band is a "do whatever you want at any power level you want" band. But I doubt it...
This is pretty awesome. I used to write processing software for airborne SAR and often wondered what it would take to just strap some stuff to my car and do it. Unfortunately blasting EM radiation in almost any useful frequency is a pretty big no-no without going out to the middle of nowhere.
I’m not understanding how moving along a single axis can generate a 2D image. Is there a second axis that moves at a right angle to the flight path (or leadscrew)? I must be missing something..
Nice. The down-range focus on the fenceposts is very good. Cross-range focus isn't as good, still impressive for a such a low-cost system. It'd be very interesting to see some images of a more target-rich environment.<p>Radar, SAR, and especially passive multistatic SAR are technologies that I'm sure we're going to see more of in future. Passive SAR (or transmitter-of-opportunity SAR) can be computationally expensive, but pieces seem to be there to build something that works really well.
I'd hire this guy. This, the homemade GPS guy, and the homebuilt apollo computer guy are all the sorts of people you want on your team to teach the young bucks a thing or five.<p>So I'd hire him.