Now we can make our stuff completely invisible.
Ohio State University engineers have invented a radar system that is virtually undetectable, because its signal resembles random noise.
The radar could have applications in law enforcement, the military, and disaster rescue.
The radar scatters a very low-intensity signal across a wide range of frequencies, so a TV or radio tuned to any one frequency would interpret the radar signal as a very weak form of static.
You realize this also means your car’s radar detector will soon be useless, too.
I think you mean “completely visible”, since this radar can see everything.
Car detectors have been useless for quite some time — they just pick up noise for the most part.
xully,
This can’t see everything.
Think Stealth craft w/ stealty radar vs stealth craft w/ noisy radar: The first can use its rader more often w/o giving itself away, the second has to be careful to ensure it doesn’t give itself away. So now we are closer to invisibility, without giving up ability.
No, I do mean completely invisible.
A stealth fighter is very hard to see on radar, but if it uses its own radar, that radar can be detected. With this technology, radar beams coming out of the fighter would be undetectable.
Today, when a fighter “paints” a target with radar, that target knows someone is shooting at them because the radar beam they are using for missile tracking is visible. An “invisible” missile would be an extremely formidable weapon indeed.
(Knocks wood)
John, you owe me a beer.
Haven’t police been using a laser reflection technology for many years now? I didn’t think radar detectors were useful any more because of that.
Obviously no one here has a Valentine One. Oh, and laser (or LIDAR) is worthless (at least in CA) since it has no judicial review.
I understand now, thanks. FYI there are projects that involve piloting vehicles using entirely pre-sensed data.
whats interesting,
It NOT using a signal, but using Ambiant noise, to carry signals back to you. As long as you have 1 point of referance for Depth, you can see everything.
Not impressed. Apparently they were already using this technology on WMDs in Iraq.
4. Today, when a fighter “paints” a target with radar, that target knows someone is shooting at them because the radar beam they are using for missile tracking is visible.
I thought there was a distinction between the low-power outputs of search/navigation radars, and the high-powered Fire Control variety.
Or, is that only for the passive radar-homing missiles which require a target to be “painted” or “illuminated” with a high-power signal so they will have a strong return/echo to seek?
i.e. typical movie scenario where the pilot can’t get a “Lock” or “Tone” from the missile’s tracking system because the radar-reflection isn’t strong and/or steady enough.
Using a passive system can be a pain…
with all the noise and focus (non-existant), then having to NOT be moving very fast…You could hear alot..BUT, even that can be defeated.
Using exiting sound signals, radio, Cellphones, wireless phones signals, could be a cool idea, and fairly simple…
You SHOULD be able to map a whole region from the air, if you do it right, and the ground targets dont have to even KNOW you are using the signal to map the area…
That shoots the market for fallout shelters.
With no warining, one moment you’ll be watching Cranky Geeks on your computer, next moment you’ll be Radioactive Airborne Toxic Particulate Incinerated Sugar Snacks.
Which is probably the better way to go anyway.
If they kill car radar detectors, I’d say its a good thing. Unless anyone can tell me a use for car radar that’s purpose is not to let you exceed the posted limit with impunity. I mean, it may be debateable, but it is the law …
First, Stealth technology relies on the reflection not returning to the source. This technology has already been defeated by coordinating (networking) spaced radars – reflection from one source is collected by another. It still works against a 3rd world technology (e.g., Iraq) but not without some failures even in Kosovo.
Second, it is not credible that this source is indistinguishable from noise. For example, even if the spectrum were exactly the same as background, the amplitude would be conspicuously high just in front on the airplane. This is just another example of military industrialists pumping up the next big sale to a diluded electorate. You know better.
reuel,
You are close, but you don’t quite get it. This technology does not try to mimic background noise; its signal is indistinquishable from background noise by discrimination circuits. There is a difference.
A radar detector can’t find signals outside of its band of sensitivity, right? It has the ability to “see” radar signals within a frequency range. Now, it recognizes a radar signal because the parameters programmed into it. The earth’s atmosphere is constantly in flux with radio signals; we give off as much RF as a small star. A radar detector works by picking out the signal with the specific characteristics it was told to look for.
It doesn’t work by amplitude, or it would track the sun. It has to sift through the radio spectrum to find the organized signal it has been told to look for. If the radar signal is a mishmash that it cannot track, it is rejected as noise by the circuit.
There will almost certainly be technologies developed to address this, but they don’t exist now. In a dogfight, there is only one radar you have to worry about: your adversary’s. There won’t be a grid of radar beacons at 40,000 feet. (Not yet, but I know the Air Force is working on drone RPV teams to escort fighter aircraft. They would fill that role well.)
Mike,
A fire-control radar would be even more detectable, as its signal strength would be higher.
Never trust a movie to teach you anything about the military. Many get some of it right, some get most of it right, but none get all of it right. Fighter movies are the most notorious for bullshit because they need suspense every second.
That’s why they haven’t used the F-117 as a fighter, only as a bomber. The moment it lit up its radar it would be visible, and it isn’t the most maneuverable aircraft in the world. If it had an undetectable radar, it would be like the Romulan Warbird in Star Trek Six that could fire while cloaked.
how about thinking it this way…
Unless you are willing to take Every signal, and Locate it, on All the frequencies… you wont find this device/plane.
Radar on ground is set for spacific ranges. If you are using this found in 90% of most cities…the only FAST way to find the scource, is to NOT have any radio traffic with in 50 miles. That includes ambiant signals, which travel on Power cables..
Best way to defeat any Stealth system is to OPEN your eyes. night time is the worse, and best way to locate these ships, would be heat and sound..
They have to go SLOW, they have to have power to glide and be stable. But they Have an engine, and it makes noise, and Heat. Even vented…there will be a disturbance in the air..
As they say, They are difficult to detect, it dont mean IT cant be done.
Again, dogfighting at altitude will not occur slowly, or give anyone time to “look”, especially in an F-22 going at supercruise.
Heat detection does work, that’s why fighters carry heat-seeking missiles. But they are USELESS at the ranges radar works.
Also, a signal means something coherent. If there is nothing coherent to lock on (again, amplitude doesn’t work) the circuit will not recognize that a radar is being used against it.
If it had an undetectable radar, it would be like the Romulan Warbird in Star Trek Six that could fire while cloaked.
Those Romulan War Birds sure were tricky little things. Too bad the Romulans all caught Warbird Flu and died. But that was John Kerry’s fault.
Alix, I would change one word in post #4. From undetectable to . The whole premise of this radar is to appear to be just just background noise, to camouflage the signals. They could be detected, but would be ignored.
Just my understanding. Except for the Romulans. That is common knowledge I just invented.
I love your questions, my friend.
I defend my use of the word undetectable, because the signal isn’t really masked in noise, it behaves as noise as to fool the detection circuit.
There will be ways to detect such a signal (an array of radars comparing their results in a computer could sniff out the “random” signal, I’ll bet) in the future.
My apologies, in #19 that should have read:
From undetectable to unrecognizable. The word camouflage will make more sense that way.
Darn, my writing is getting almost as unrecognizable as my thought process.
Nonsense! Radar detectors need only be built to emulate the receiver portion of the the radar transmitter-receiver.
18, radar ISNT infinate. and seeing past about 40 miles is inaccurrate, and takes LOTS of power.
its interesting you say DOG fight. at super sonic speeds, you cant SHOOT BULLETS or ROCKETS. they will appear right in your face.
The last part is good. BUT, if you use existing signals, you try NOT to be the same as someone on a cellphone, its Garbage.
NOw if you could use signals already residing in the area…and clean the backgroound, as from an audio signal/radio tower/cellphone already in use, there IS NO signal sent. Only recieved.
As I said, Radar detectors are NOT set to pickup common signals. Its a PAIN to figure out their locations(so far), but making a 3D image of Incoming signals, and there Lacations would be the ONLY way to find this craft. Insted of using a 386 processor and a BIG dish, you would need a P4+ to render all the data.
22.
NO…
This is like being in a crowd of 2000 people and trying to pick 1 voice out of ALL of them… It can be done, but takes a bit of doing.
Mr. Fusion.
Your point. unrecognizable is better.
Alix, thank you, but damn I sure learned a lot from your (ahem) lecture. Not only is it informative, but even I understood most of it.
ECA, you too deserve an honorable mention for clarifying this topic. Your summary in #23 really hit home.
I think, it could be done…But you would need someone searching the channels, for a Pulse only signal, Nothing with voice or data.