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Chinese Researchers Announce Radar Invisibility Cloak with Illusion Cap

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Chinese Researchers Announce Radar Invisibility Cloak with Illusion Capabilities
Posted on February 24, 2011 by Editor

A Chinese research team from Southeast University in Nanjing have announced that they have found a way to change the way radar waves interact with an object. Researchers Wei Xiang Jiang and Tie Jun Cui used advanced metamaterials, sometimes used to guide light in unique ways, to similarly guide radio waves, thus changing how the object appeared in a radar scan. The New Scientist explains the experiment:

Copper conducts electricity well and reflects incoming radio waves, giving it a bright radar signature. To alter this behaviour, the team built a device made of 11 concentric rings of circuit boards etched with small metal-lined channels that prevent electromagnetic waves reflecting away. Instead, they guide the waves in a direction that the researchers choose specifically to make the hidden object appear to have different electrical properties.

Many of you are probably saying, “so what?” Admittedly, it’s not very exciting in and of itself that some guys were able to make copper look like porcelain to radar. But then one of the researchers says the magic words that will make your ears prick up.

Similar illusion devices could eventually be used for stealth technology: for example, to “convert the radar image of an aircraft into a flying bird”, Cui says.

There’s the payoff. Currently, stealth technology relies heavily on airframe shapes and materials to deflect or change how they are perceived on radar. The F-117 Nighthawk is a prime example of how shaping the airframe can dramatically alter the radar image.

The hypothetical device that the Chinese team describes has the potential to change stealth design by making many more aircraft designs stealthy with a device rather than a design. Something like a massive cargo plane could perhaps be made to look much, much smaller but still carry huge payloads.

There are, of course, limitations to the concept. Many stealth designs, like the B2 Spirit, use recessed engines to help mask the heat put off by the aircraft’s propulsion system. A radar cloaking device won’t be able to help with that, obviously.

Moreover, the Chinese device currently only works when viewed from one side, and the radar image was still the same size as the original object. This is a proof of concept, but the development of this technology will almost certainly shape the design of future aircraft.

(via The New Scientist, image via Memory Alpha)
*ttp://daringminds.com/new/chinese-researchers-announce-radar-invisibility-cloak-with-illusion-capabilities/
 
Illusion 'cloak' makes you see what's not there
* 24 February 2011 by Rachel Courtland
*ttp://www.newscientist.com/article/mg20928005.800-illusion-cloak-makes-you-see-whats-not-there.html?DCMP=OTC-rss&nsref=online-news

First black hole for light created on Earth
* 17:13 14 October 2009 by Anil Ananthaswamy
Now Tie Jun Cui and Qiang Cheng at the Southeast University in Nanjing, China, have turned Narimanov and Kildishev's theory into practice, and built a "black hole" for microwave frequencies. It is made of 60 annular strips of so-called "meta-materials", which have previously been used to make invisibility cloaks.
*ttp://www.newscientist.com/article/dn17980-first-black-hole-for-light-created-on-earth.html

Study: US, Chinese researchers engineer invisible cloak
Jan 18, 2009 by ■ Chris V. Thangham -
In a joint research by the U.S. and China, scientists and the universities in North Carolina have created an invisible cloak that mimics mirages in desert.
The study was conducted at the University of North Carolina, Duke University and supported by the US Air Force Office of Scientific Research and National Science Foundation of China.
*ttp://www.digitaljournal.com/article/265454

Invisibility Undone: Chinese Scientists Demonstrate How To Uncloak An Invisible Object
ScienceDaily (Sep. 4, 2008)
*ttp://www.sciencedaily.com/releases/2008/09/080903073016.htm
 
It's been accepted to Physical Review. Very good article then! I'll have to look at their original article, it sounds very very interesting! This is cutting edge material science research!
 
from same scientist related to cloaking published on nature

Three-dimensional broadband ground-plane cloak made of metamaterials
* Hui Feng Ma1
* Tie Jun Cui1
*ttp://www.nature.com/ncomms/journal/v1/n3/abs/ncomms1023.html
*ttp://www.nature.com/ncomms/journal/v1/n8/abs/ncomms1126.html
 
from same scientist related to cloaking published on nature

Three-dimensional broadband ground-plane cloak made of metamaterials
* Hui Feng Ma1
* Tie Jun Cui1
*ttp://www.nature.com/ncomms/journal/v1/n3/abs/ncomms1023.html
*ttp://www.nature.com/ncomms/journal/v1/n8/abs/ncomms1126.html

GREAT! It's not paywalled!
 
Study: US, Chinese researchers engineer invisible cloak
Jan 18, 2009 by ■ Chris V. Thangham -
In a joint research by the U.S. and China, scientists and the universities in North Carolina have created an invisible cloak that mimics mirages in desert.
The study was conducted at the University of North Carolina, Duke University and supported by the US Air Force Office of Scientific Research and National Science Foundation of China.
*ttp://www.digitaljournal.com/article/265454

Very odd that something like this be a joint project with China and the US (with US funding coming from USAF)

but this paper has been published in Science.

Broadband Ground-Plane Cloak (the principal investigator is a Chinese scientist)
 
Very odd that something like this be a joint project with China and the US (with US funding coming from USAF)

but this paper has been published in Science.

Broadband Ground-Plane Cloak (the principal investigator is a Chinese scientist)
Because China is ahead of USA in this area of science so the US is leveraging Chinese expertise here. The same does not happen the other way around where US advantages in potential military technology is strictly controlled. That is unless of course you believe rumors and other unconfirmed reports from dubious sources that propagate American right-wing media.
 
Because China is ahead of USA in this area of science so the US is leveraging Chinese expertise here. The same does not happen the other way around where US advantages in potential military technology is strictly controlled. That is unless of course you believe rumors and other unconfirmed reports from dubious sources that propagate American right-wing media.

We can't honestly be as stupid as to give away tech with something in return...
 
Ah, the concept of destructive and constructive interference

---------- Post added at 06:31 PM ---------- Previous post was at 06:30 PM ----------

If this gets successfully integrated, this will be a killer device for use on fighter, bomber, and EW aircraft
 
Ah, the concept of destructive and constructive interference



I think meta-materials are not based on simple constructive and destructive interference patterns. More about parts of the material acting together to achieve properties that are not found in nature. I could be wrong, I have read what they published and this not my field.
 
I think meta-materials are not based on simple constructive and destructive interference patterns. More about parts of the material acting together to achieve properties that are not found in nature. I could be wrong, I have read what they published and this not my field.

Destructive and constructive interference is pretty much the only way to weaken or strengthen radar waves with radar waves
 
Destructive and constructive interference is pretty much the only way to weaken or strengthen radar waves with radar waves

For it work on constructive/destructive interference basis, Bragg's law (relationship between angle, slit width, and interference) states that the constructive/destructive slit width would need to be in the cm-meter range.

95ea40074637575d1b01df21b5a8159d.png


where n is an integer, λ is the wavelength of incident wave, d is the spacing between the planes in the atomic lattice, and θ is the angle between the incident ray and the scattering planes.

em_spectrum.jpg


Radar is in the cm-m wavelength range.



Meta-materials are as far I know on the nanoscale.
 
For it work on constructive/destructive interference basis, Bragg's law (relationship between angle, slit width, and interference) states that the constructive/destructive slit width would need to be in the cm-meter range.

95ea40074637575d1b01df21b5a8159d.png




em_spectrum.jpg


Radar is in the cm-m wavelength range.



Meta-materials are as far I know on the nanoscale.

There's a chance that they developed a way to bridge cm and nm.

Either way, if the displacement of the waves are correct, waves will be interfered
 

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