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> Another innovation, he says, is the resolution at which Capella’s satellites can collect imagery. Each pixel in one of the satellite’s images represents a 50-centimeter-by-50-centimeter square, while other SAR satellites on the market can only get down to around five meters. When it comes to actually discerning what you’re looking at from space, that makes a huge difference. If that's what is available to civilians…
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This is likely the best recent example (from last year): https://www.thedrive.com/the-war-zone/29634/trump-tweets-int...
It doesn't looks like SAR to me(there are shadows, for example). More like standard optical image(the resolution and details are amazing, if it's a satellite, which is doubtful given the angle).
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If you want to block SAR, just set up a big corner reflector near you. It'll completely blind the part of the image near you. It would also draw a lot of attention to you... So maybe not the best approach if you're trying to hide.
Are you sure a corner reflector will work? The entire premise of the synthetic aperture is that the transmission and reception are distant from each other, but a corner reflector will reflect back to the location of the transmission - i.e. it will entirely miss the receiver.
It's true that the SAR antenna has moved a little bit by the time the transmitted signal is received. However, the signal is moving significantly faster than the satellite - with a 600km orbit, velocity is ~8km/s - so the roundtrip time is maybe 0.04s, meaning the satellite has moved 320m. That's about 0.2 degrees from the point of view of the reflector.
The synthetic aperture is not just the distance covered in the round trip of a single chirp, but the distance covered during the imaging process. A SAR typically produces chirps constantly (in the tens to hundreds of Hz) and digitises the responses. All of the energy of all those responses can then be combined to form the image.
If the corner reflector is in a fixed location, every chirp will have a spike in the response corresponding to that location.
Earlier quoted context omitted.
This is likely the best recent example (from last year): https://www.thedrive.com/the-war-zone/29634/trump-tweets-int...
It doesn't looks like SAR to me(there are shadows, for example). More like standard optical image(the resolution and details are amazing, if it's a satellite, which is doubtful given the angle).
> The satellite beams down a powerful 9.65 GHz radio signal toward its target, and then collects and interprets the signal as it bounces back up into orbit. Years ago there were lots of articles about X-ray backscatter vans, owned by NYPD but probably also other jurisdictions. One of the concerns was you'd never know when they were scanning you and looking inside your car. But of course, though these active systems a…
9.65GHz would be outside the range of most common SDRs, but other than that it would be like detecting any other radio transmission. You would need a sample to know it's the satellite in question and not some other noise on that band, and it would be vulnerable to false positives unless the sample is unique.
At what point are we going to be able to distinguish those who are being always watched from the paranoid schizophrenic?
LOVEINT tells us it's really just a matter of time until we hear of some worker who goes postal after tracking his love interest in everything building they go in.
> The satellite beams down a powerful 9.65 GHz radio signal toward its target, and then collects and interprets the signal as it bounces back up into orbit. Years ago there were lots of articles about X-ray backscatter vans, owned by NYPD but probably also other jurisdictions. One of the concerns was you'd never know when they were scanning you and looking inside your car. But of course, though these active systems a…
One of the problems would be that detecting such a thing in an omnidirectional way would be problematic and difficult, the horn antenna described above would have the vast majority of its gain when aimed in one particular azimuth and elevation.