A New Satellite Can Peer Inside Buildings, Day or Night
futurism.com
futurism.com
The NRO Topaz satellites are the successful radar development of the two prong Future Imaging Architecture (the optical component failed, which was to be the successor to Keyhole [of which the Hubble Space Telescope is derived]) should be assumed to have capabilities far beyond those of this company.
https://en.wikipedia.org/wiki/Future_Imagery_Architecture
https://www.space.com/23871-air-force-spy-satellite-launch-n...
https://www.nytimes.com/2007/11/11/washington/11satellite.ht...
^ A very well put together long read from the Times on black world contracting chaos, exemplified by these satellites.
By physics, and computing power.
For any stable circular orbit, a satellite can only fly that fast, and the radio window would only pass so much of radio spectrum.
But you are right talking about computing power. SAR work in a very different way from optical imagery and data generation/processing is quite a huge difficulty.
Thompson's adage of when the going gets weird, the weird turn pro suggests that the tinfoil hat crowd could be able to corner the emerging domestic Faraday cage market.
EDIT: On a more general case, I wonder how expensive and feasible it would be to cover the roof/ceiling and walls with an array of 9ghz emitting "pixels" with the wire mesh behind that. Then show the satellites whatever image you want. Make it look like funny stuff is going on inside for their own amusement.
Wouldn't be able to account for the different angles the satellite might take pictures from, though. Unless you track it.
It would also draw a lot of attention to you... So maybe not the best approach if you're trying to hide.
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.
https://www.westmarine.com/WestAdvisor/Selecting-a-Radar-Ref...
Similarly there's monitoring of AIS by Iridium, but pirates and drug lords turn those off.
Bob: "Hmmm, anyone preventing us from getting a look means they are subversive. Get a no-knock warrant to investigate that location. Only illicit activities can be taking place there."
In this case, being "invisible" actually makes you more suspicious which only brings their attention upon you that much more intense.
It's weird to hear places that were expected to be private to be called 'gaps' like they should be visible but weren't until we had the technology to fix that.
> Capella launched a platform allowing governmental or private customers to request images of anything in the world
'or private customers' adds to the looming creepiness of our future.
Looking at the examples of 'ghostly buildings', it seems these are just combining different perspectives as the satellite moves. It isn't actually seeing inside the building, just 3D rendered to look transparent.
10Ghz has (optimistically) a building penetration loss of 25dB [1], with any reflections back also seeing 25dB loss. I don't think this is workable with current satellite power flux density regulations. At least not at 10Ghz.
[1] ITU-R P.2346-1 https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-P.2346-1-201...
Edit: the claims to seeing 'individual rooms' are not backed by any examples, but maybe natural corner reflectors could rarely give a return. Still wouldn't be able to see anything within the room.
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 are invisible to human eyes, they do have to send out pretty strong signals. So I wonder if a kind of sousveillance is possible. Can we have devices that detect the signal being directed at the target, and alarm and publish that info? Both individuals could know if/when they are being imaged, and the public could see some patterns in who they look at. Anyone aware of how hard a detector would be to build?
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.
If that's what is available to civilians, I'd like to see what 2020 spy satellites can do.
https://www.thedrive.com/the-war-zone/29634/trump-tweets-int...
More like standard optical image(the resolution and details are amazing, if it's a satellite, which is doubtful given the angle).
The biggest secrets within US Reconnaissance Satellites isn't really optical clarity anymore, it is their capabilities in other spectrums (and have supported at least infrared for 30+ years, but with signals intelligence well beyond that since).
[1] https://apnews.com/press-release/pr-prnewswire/d35f7cb315af0...
When it does, it will be massively destabilizing as it places the "invulnerable" second strike capability that guarantees deterrence against peer states at risk.
It never been such to begin width, at least by the late cold war, some portion of missile subs were reliably tailed by adversaries without any high tech trickery.
North Korea, Russia, and China each already have more submarines than USA, and would have no problem to put 10 subs to tail each Ohio.
It takes a nuclear sub to trail a nuclear sub. NK and China have exclusively, and primarily (respectively) diesel subs. These have to surface and run their engines to charge batteries. They cannot make 20+ knots submerged for long, and they cannot track deeply submerged submarines from the surface. Surfacing and running diesels would make their presence known. They cannot range far from port, and certainly cannot track missile boats under the arctic ice.
Russia has a sufficiently large nuclear fleet, but it is outdated and probably outclassed by US technology. There is probably greater disparity between the powers than existed during the cold war, at which time deterrence was credible.
Newer ones are directly sensing density, and temperature changes in the seawater by sensing Raman shift, and are supposedly much better. No known data in public of course.
Even in very well mapped areas, think of the effort in the Indian ocean to find MH370, this would require the assumption that the sub is moving, which is not always the case, e.g. if the sub halts propulsion and drifts with a current.
But there is no need for high resolution and the wake of the sub stands out starkly even with a large field of view. So I'm not sure it can evade detection by halting propulsion and drifting. The point at which it halted would be known and it would be detected as soon as it restarted, unless it was carried by an unknown current far enough to be out of view of the satellite.
First of all, security. If your opponent has that kind of capability, you cannot meaningfully deploy tanks or any other vehicles anymore. Even infantry will suffer massively once the resolution goes up a notch. On a much smaller level, one could easily detect brake-in attempts on unguarded property.
Second, industrial espionage. Want to know how much the competition buys/sells? Plug this data into some form of image recognition.
Third, government control. From traffic over demonstrations to "unsocial" behavior, governments at the municipal level could easily inspect "their" people and control their behavior much more efficiently.
But yeah, I agree with you about the potential. Also, presumably a constellation imaging the same location from multiple angles could synthesize a super high resolution 3D image?
Governments can now spy on their people via old fashioned surveillance: wire-tapping, informants, social media analysis, etc. If a nation has the checks and balances to prevent that, then it's very likely they'll be able to prevent satellites peeking into your home. If not, it could potentially be another tool in their oppression toolkit, but not terribly efficient compared to the mountains of tools they already have, like traffic light CCTV cameras, highway tollbooths, tracking of credit card payments, tracking of internet-connected personal devices, etc, etc.
I think the main thing preventing widespread use is that once you start using these technologies on a larger scale, then people can identify it's capabilities (making it less effective, especially against the highest value targets) and also creating public backlash once a sufficient number of 'normal' people have been targeted (without getting 'disappeared').
Another part is that you have equal-weight matchups occurring at each level. Your expensive and highly capable platforms will be busy targeting the adversarial platforms that pose the most threat to them (usually expensive systems as well), leaving less time/resources to commit to the lower weight targets. For example, you're not going to get as much air support from either side if the planes are dealing with each other.
Of course that is highly generalized as the whole system works as an interdependent mesh.
Even infantry to infantry conflicts against a peer-like adversary would result in unacceptable losses for today's society.
"This is part of why I don't expect any future direct wars between world powers."
I somewhat agree with that. I think it could be possible in a scenario similar to that video game (Solid Snake?) where countries fight each other in highly mechanized/autonomous fashion - limited loss of life, but high economic costs until one collapses. But yeah, probably more likely to be a cyber war or cold war scenario. Technically we are in a loose proxy war with Russia based on what's going on in Syria.
https://www.theguardian.com/us-news/2019/aug/02/pentagon-bal...
While it would be cool to have the capability, it won’t happen soon. Not because there aren’t people smart enough to solve the technical problems, but because nobody has navigated the political issues. The people with the resources to do so are happy enough with the money they are receiving from the governments of the world.
It's pulsed as well - you send an RF "chirp" at a sub-1kHz pulse frequency. Depending on imaging mode the average power draw is probably in the 500W-1kW range.
That had a much larger resolution (6m rather than 50cm), but the resolution is a function of frequency and antenna design as much as power.
The SAR concept essentially creates an image by sending out a known RF chirp and then, for each pixel of the image, correlating the response with the expected signal from that pixel. That correlation means that even if the received signal is below the noise floor you can create an image.
Presumably solar panels recharge a battery when it can, but continuous operations seem out of the question without some pretty large panels.
Maybe I'm underestimating modern solar panels or something.
Even easier, Capella-1 is in a sun synchronous orbit, so it will always pass overhead at the same local time, at noon or midnight.
https://www.dhs.gov/sites/default/files/publications/Radar-T...
The resolution of the image is proportional to the bandwidth of the waveform and the distance traversed by the satellite during the collection process.
This article is a bit of an exaggeration and Capella is certainly not the first or only SAR service.
Can anyone tell me if 9.65 GHz waves can penetrate concrete / wood homes?
If commercial satellites have reached this capability, military ones are definitely far ahead.
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.
As an EE, I consider it important to understand that nothing at any level in your technology stack from silicon to SAAS to smartphones is black magic. This is just an application of the physics of high frequency electromagnetic signals.
I haven't personally done work with SAR, but I imagine it's much the same as dealing with EMI/EMC in PCB development: extend Maxwell's equations from a simple case to the general principle, simulate, test, and tune. I'd have to go back to my textbook and review to figure out the exact mechanisms and the limiting factors for resolution and power, I think I have Johnson's "High Speed Digital Design: A Handbook of Black Magic" on a shelf around here somewhere...
"Hello this is the EU, you satellite does not comply with GDPR".