Radar That Sees Through Walls Built In Garage 63
szczys writes: Building radar in his garage is nothing new to Greg Charvat. He has a PhD in this stuff and has literally written the book (and a University course) on building your own radar system. This time around it's Phased-Array Radar. This is more than just judging the speed of a baseball or Ferrari. This rig can actually see through walls. Greg uses the example of a soda can to illustrate the quality and resolution possible from this type of system.
What's so special in walls built in garage? (Score:3)
I'm sure you can use various radar-blocking materials to build walls in a garage, not just wood and plastic, but also metal. So what's so special in factory-made ones that they can't be penetrated by this radar? Is it patented? Or a government secret?
Re:What's so special in walls built in garage? (Score:5, Funny)
I think the writer is saying on average people are more likely to build with plywood or drywall in their garage instead of less permissive materials like brick, concrete, or metal.
So, statistically speaking, a radar system is more effective against walls built in a garage than walls built outside of a garage.
As usual, the article may provide clarification, but I've found I can avoid the trouble of reading them by simply making wild assumptions.
Re: (Score:2)
In TFA, it said he saw "a 12 oz soda can through a 4” thick concrete wall at a stand-off range of 20".
Re: (Score:1)
But who's building walls in his kitchen?
Re: (Score:2)
How are the kitchen-built walls different from the garage built walls?
Re: (Score:1)
Re:What's so special in walls built in garage? (Score:4, Funny)
Temba, his arms wide. ;-)
Re: (Score:2)
Re: (Score:2)
Depends... did you install 3-phase industrial power in the garage to power the radar? No? Then you'll have to move the installation into the garage, most likely.
You want to see through walls across the street? I guess you better start buying up used smoke alarms.
Re: (Score:2)
I'm glad you asked this question! All walls built within garages are effectively invisible to this radar. If the wall is removed from the garage and installed elsewhere it is still a garage-built wall and continues to remain invisible to the radar system.
You may be thinking, "What if I take one of these garage-built walls and build a garage out of them?" Let me warn you against this. We've tested this very scenario and it didn't turn out well. Lemons started spontaneously combusting and I think we might hav
Re: (Score:2)
How are the kitchen-built walls different from the garage built walls?
Well to start with, the usual construction materials are ginger bread, or (for people that don't have ginger servants on hand) chocolate "bricks."
Now the Little Brother can watch too! (Score:3)
Move away, NSA and other Big Brothers — real and wannabes. The Little Brother can watch too now.
No need for time-travel. "Happy goldfish bowl to you, to me, to everyone"
Re: (Score:2)
I can't say I'm any happier about the idea of random people being able to peer into a house and see who's home or not anymore than I am enamored of the idea of cops doing it without warrants. I wonder what is a burglar's time-to-break-even for an investment in building one of these?
Re: (Score:2)
My friend actually was punched without warning while randomly walking down the street, and his nose was broken. And I have studied martial arts. Unrelated facts.
=)
Re: (Score:2)
Not sure you are the same A.C. or not?
Anyhow, you misread my post.
I simply stated an amusing and, as I said, "unrelated" pair of facts based serendipitously on what the previous respondent happened to write. They bear no relation to the price of rice in China.
So calm down. =)
And no in fact, no, years of martial arts preparation should do very little to protect you from a random, unprovoked, and stealthy assailant.
Nonetheless, since you asked, I think there are other very good reasons however for studying m
Comment removed (Score:4, Informative)
Neat (Score:3)
This is exactly the sort of thing i love seeing a project and nice explanation on. This sort of thing will never be my career path, but, is the sort of thing I might play with as a hobby project and I love seeing the areas a person can get into without much formal training expand.
Of course, I already have a use for such a thing but.... I think it will be easier to use a small drill and a camera to find out if the rumors of my great grandmother's old safe still being in the walls somewhere (plastered over of course) is true.
Have to imagine that will be cheaper and faster (if not cooler) than building one of these.
Re: (Score:2)
Wouldn't one of those stud finders be easier than drilling a bunch of holes in the wall?
Re: (Score:3)
Or use a metal detector? Chances are the safe will not be too deep in the wall, and unlike pipes and wires, which would give off short beeps, a safe would register an entire square face to the detector.
Re: (Score:2)
Nope stud finders wont even find studs in my house because its old enough to have horse hair plaster, so the studs are covered by horizontal wood slats. SOME stud finders kinda work, most don't work well (admittedly, its been a few years, maybe they got better?)
Also it wouldn't really identify the object, just that it looked like something more solid was there.
The reply of metal detector might work better....but there is also a metal chimney pipe for an old gas fireplace that used to be in the room also in
Re: (Score:1)
if you have 50 bucks, http://www.franklinsensors.com... [franklinsensors.com]
Re: (Score:2)
Electromagnetic fields and public health: radars and human health, Fact sheet N226 [who.int]
WHO has also concluded that there is no convincing scientific evidence that exposure to RF shortens the life span of humans, or that RF is an inducer or promoter of cancer.
Re: (Score:1)
In other news: All researchers collecting scientific evidence that exposure to RF shortens the life span of humans died for unknown reasons before they could finish their research.
Bert
Kidding
Re: (Score:1)
Yes, it can cause ionization by bumping electrons around
No. Any electrons that can be "bumped" around by EM radiation with wavelengths longer than UV are already in the conduction band. In other words, the ionization already happened and any induced current occurs in "loose" electrons... or, more likely, existing ions in solution.
It's called non-ionizing radiation for a reason.
Re: (Score:2)
Yes, it can cause ionization by bumping electrons around
No. Any electrons that can be "bumped" around by EM radiation with wavelengths longer than UV are already in the conduction band. In other words, the ionization already happened and any induced current occurs in "loose" electrons... or, more likely, existing ions in solution.
It's called non-ionizing radiation for a reason.
Wait a sec. I thought that was non-unionizing radiation.
I'm gonna havta rethink my support of that now.
Re: (Score:2)
Nonsense, burns are well known causes of skin cancer. If your microwave is burning you, that is just as dangerous as the Sun burning you.
The easy tinfoil-free way to know if the radar is increasing your cancer risk: Does it hurt yet? Burns hurt. Stay safe. If your microwave causes pain, unplug.
walls that were not built in a garage ? (Score:5, Funny)
Be careful making stuff cheap and easy. (Score:5, Informative)
In KYLLO v. UNITED STATES [google.com] , the Supreme Court held in 2001 that:
in determining that use of a thermal imaging device whose output was used to establish cause for a search warrant was, itself, a search that required a warrant.
By making intrusive surveillance devices available inexpensively (perhaps by showing hobbyists how to build their own), such devices could move (as planes have) into "general public use" and then be usable by police without a warrant to surveil areas normally off-limits to them without a warrant.
Re: (Score:2)
By making intrusive surveillance devices available inexpensively (perhaps by showing hobbyists how to build their own),
How dare those scum at MIT [mit.edu] teach people how to surveil their neighbors and stuff.
Re: (Score:1)
I doubt a home-built phased array radar will ever be considered "in general public use."
Besides, these devices only see thru walls built inside a garage, which would generally require a search warrant to see either side of...
Re: (Score:2)
When building walls inside your garage is outlawed, only outlaws will...
Re: (Score:3)
I cannot fault your analysis of that particular sentence since I'm certain that some lawyer somewhere will eventually argue that when the "not in general public use" criterion is absent it somehow becomes a "reasona
Re: (Score:2)
I think we are seeing the stage being set for a similar situation with drones.
If the FAA rules allow private drones to fly at low altitudes over private property without consent of the person controlling the property and the legislators don't pass laws restricting this (the FAA doesn't make rules about privacy - safety is their charter), the expectation of privacy will be reduced as more and more private citizens fly drones at the lower altitudes. Then, police will be free to do so as well and peer into you
Re: (Score:2)
In KYLLO v. UNITED STATES [google.com] , the Supreme Court held in 2001 that:
in determining that use of a thermal imaging device whose output was used to establish cause for a search warrant was, itself, a search that required a warrant.
By making intrusive surveillance devices available inexpensively (perhaps by showing hobbyists how to build their own), such devices could move (as planes have) into "general public use" and then be usable by police without a warrant to surveil areas normally off-limits to them without a warrant.
Almost makes it sound like they won't need a search warrant anymore, as long as enough people build these things and put them into general use.
Hmm (Score:1)
The same sort of thing has been reduced in size and cost for multirotors, it is not publicly available yet, but try to imagine a consumer drone that can see thru walls.
Re: (Score:2)
I know, talk about overkill. What a waste of bandwidth.
Re: (Score:2)
Or, if you want to save some money, just wrap the room in chicken wire and aluminum foil.
Works for hats, too. And you can keep your phablet under the hat when not in use.
Electronic Countermeasure (Score:2)
Put on your tinfoil hat and turn on your microwave oven.
CAUTION: do not stick your head in the microwave.