Radio amateur & inventor secures patent on Invisibility Cloak detection

Demonstrating again that a foundation in amateur radio can foster many achievements.

73, John, WØPV

Fractal Antenna Systems, Inc. (‘Fractal’) today announced it has secured patent on a method to detect invisibility cloaks and related stealth metamaterials, thus preventing hostile military assets from being hidden from radar, and decreasing the potential for sparking conflicts.

Detailed in US patent 11,408,976 and patent pending, the cloak detection technique – dubbed LPASS™ – is a new radar method that looks for tell-tale signatures of cloaked objects. that are made invisible by ‘metasurfaces’ (skins made of metamaterials), including satellites, planes, vessels, or UAV’s. At the frequencies where the cloak works, called its ‘passband’, radar tries to bounce signals back from the target but the cloak stops that reflection, and the target remains hidden. Beyond the cloak’s passband, radar transmitters are hampered by lower power limits, and thus poor at pinging cloaked targets both in and out of a cloak’s passband.



Inventor and firm CEO Nathan Cohen (aka Chip @W1YW) showed radar transmitters don’t need to transmit outside of the passband, since metasurfaces have a failure mode that produces nonlinear, heterodyned RF ‘hash’. High powered radar systems may be thwarted to detect targets that are cloaked in the passband, but their transmissions hit the target and excite this hash of heterodynes at much higher and lower frequencies where the cloak doesn’t function and the target is not hidden. On receive, a radar antenna picks up these frequencies, correlated with the transmitted signals, filters out most of the noise, and leads to a unique reflected signature of the target.

In the past, radar was considered the trump card that succeeded at target detection, a task made difficult by stealth techniques. Because they are less expensive to implement than other radar stealth methods, metasurfaces are used extensively outside of the USA, highlighting the urgent need of LPASS™ as the remedy of Pandora’s burden. Those countries that may seek a tactical advantage by retrofitting war machines with metasurfaces to hide from radar now have to face a revision to their prior assumption of hidden assets.

Cohen invented the invisibility cloak (patent 8,253,639) in 2003 and clearly saw the need to stop their destructive use, by creating LPASS™ shortly after. New patent 11,408,976 is a public message that invisibility cloaks were not invented solely to be toys of war. Metasurfaces can do more than hide objects and have many useful applications. Cohen states the firm’s recent patents on ‘fractal license plates’ for satellites (patent 11,249,178), enhanced radar road reflectors for autonomous vehicles (patents 10,901,082, 11,175,400), and smaller, wideband directional antennas (patents 10381738,11128052) are a few of many positive spinoffs of his invisibility cloak/metasurface inventions.

"Metamaterials overall have a terrific future, if we encourage their use in applications which improve the human condition and that promise of tomorrow."

 

Thanks for posting John .

The caption for the photo is:

Inventor Nathan Cohen leading a microwave invisibility cloak demonstration. Cohen invented the invisibility cloak (patent 8,253,639)and now FRACTAL’s patent 11,408,976 makes radar capable of seeing cloaked objects. Courtesy Fractal Antenna Systems, Inc.

The cloak is layers of a 'metasurface'.

Basically its a microwave cloak demo making a chunk of a tree go away. Audience was composed of radar/phased array conference attendees, and a curious mailman.

No mail was harmed in this demonstration.

The new technique allows detection of cloaks and metasurfaces in general, so now cloaks are bad candidates for stealthy applications. SUCH as PRC fighter jets, as discussed in the later sections of this youtube video--


(9) 《大国重器（第二季）》 第八集 创新体系 | CCTV财经 - YouTube

See: 42:14

Of course, if you want to believe they are making pretty prints for grandma's sofa, well, so be it.

 

..and here is a dailymail article from a while back.

China claims it has created invisible material for fighter jets | Daily Mail Online

My experience is that daily mail articles are either straight-on truth or absolute BS. In any case, China can claim nothing regarding 'creating' invisibility cloaks. The work was done by others and used without knowledge nor permission. You can decide what you want on that.

I always knew those x ray specs we saw advertised as kids would have impact on my life;-)

 

Eh, no biggy...
David Copperfield made the statute of liberty disappear.

 

Congratulations! This is very cool. Metamaterials and their use in cloaking is fascinating.

 

Heck, Ham radio made a bunch of my money disappear…

 

Remarkable ! Congrats Chip & Co.
Let's hope Star Trek's USS Enterprise is suitably modified
G3SEA/KH6

 

Very nice work, Chip & Co. Anything we can do to keep China off balance is fine by me.

But go ahead and admit it. You really are a mad scientist!

73,

--Kurt

 

The "Klingons" will be very upset! More POWER Scottie"

 

You and ME both. by by...

 

This has me really concerned!! I hope Chip has considered this and acted accordingly!

But in all seriousness, WELL DONE Chip!

...............Bob

 

I appreciate that this is an international forum and that there are many amazing, smart, hard working hams in PRC.

My issue is with policy, not individuals. Basically, if you do not recognize the talents of those not in your country, what does that say about the way your citizens are truly viewed?

Having a sense of ethics should not be a weakness.

There are other ways to do stealth. They cost more. That means they will be used far less. Thus reducing the likelihood of someone doing something stupid.

This takes one (cheap) way off the table.

Many sincere thanks to all for your well wishes

73
Chip W1YW

 

Definitely I was PO'ed on this example...and acted constructively.

 

I view the Chinese people and the Chinese communist government as two very different things. The first are not our enemy--the second certainly is.
My own daughter-in-law is Chinese and my grandson is Chinese-American both of whom I love dearly. The CCP not so much.

Naturally, others are entitled to their own opinions.

73,

--K

 

For me it wasn't so much ham radio but more my wife's credit card.