Fractal Antenna Systems,
Inc. today announced development of a new metamaterial technology that uses
fractals to make layered, partless antennas and related electronics. Fractals
are complex geometric shapes built up from a repetition of a simple one, while
metamaterials are composites with unusual properties not found in nature. These
new antennas, called "metacloak™" antennas, have unique performance
abilities in bandwidth, gain, directivity, and versatility of form factor.
“Previously antennas had attributes in many form factor and performance
but these new antennas are unprecedented”, notes inventor Nathan Cohen,
the firm. The new antennas have layers that are partless, with no electrical
connections, are lightweight, have no ferrite or exotic materials, and are easy
make and implement. They can be far smaller and far thinner. Built up as layers
separated printed circuits to form a covering or ‘cloak’, the technology
to other EM spectral regimes, in addition to RF.
The cloaking layers use close-spaced fractal resonators, tiny partless circuits,
accomplish the effect, and Cohen notes that the scientific community has
commonly called close-spaced resonators metamaterials. The firm owns the patent
on fractalized resonators systems, as used in these metacloak™ antennas,
many patents and pending patents on this and other metamaterial technologies.
“You just can’t optimize nor render practical this new class of
fractals and our technology”, added Cohen,” as the smaller size
bandwidth attributes of fractal resonators enable the new metamaterial
advantages”. Cohen also points out that: “The technology has also
led to fractalbased
arrays that are far smaller than expected from their gain, while maintaining
very broadband ability.”
The new antenna technology builds on the foundations of the metamaterial
physics of plasmonics, first applied by Nobel Prize Winner Gugliemo Marconi
1919 patent, and also seen in an obscure type of antenna called a CCD, invented
1961. “These historical technologies hinted at something beyond their
possibilities, but sometimes it takes a new twist to open up a field. We use
in plasmonics to get the currents to be slowly varying across the entire aperture
within a wideband, dropping off at the physical boundary conditions. FRACTAL’s
team had the know-how to be there first and has been working on developing the
technology for sometime”, noted Cohen.
As an example, a conventional monopole (Marconi) antenna was snugly covered
by a slip-on cloak of fractal metamaterials. Instead of the cloak blocking out
antenna’s emissions, it dramatically enhanced and controlled the bandwidth
gain. Both the performance enhancements and simple method of achieving them
constitute a breakthrough in the antenna field. “To take a simple and
understood antenna and produce something previously unrealized, with a slip-on
tube, was one sweet moment. It redefines a field. The effect is transformational”
said Cohen. The cloak approach applies to most types of conventional antennas,
such as patches and slots, as other examples.
The firm first publicly showed the new technology in a live demo at a colloquium
at Harvard University in April. Many dozens of scientists; engineers; government
researchers; patent attorneys; students; and antenna experts have witnessed
“Metacloak™ antennas and their array applications are far and
away the most
important applied applications of metamaterials to date, taking that field out
science fiction and research stage and well into applied reality”, asserted
Cohen believes that the new metacloak™ antennas leapfrog developments
pursued by other researchers, by 5 to 15 years. “It’s common for
us to be far ahead
of the pack, and we always have a lineup of new technology to roll out”,
For example, in March, 2009, the firm disclosed the world’s first wideband
metamaterial invisibility cloak, which also uses fractal metamaterials in a
application. Shortly before, other researchers published predictions in prestigious
journals that wideband metamaterial invisibility cloaks could never be made.
The new antenna technology is expected to allow antennas to go in many places
they haven’t been used before, especially in conformal or hidden platforms.
be used to integrate antenna onto surfaces used for other things, thereby making
the separate antenna platform notion a relic in many cases”, notes Cohen.
sees the new technology as a logical extension of its core technologies and
and versatile addition in solving challenging problems in electromagnetics.
reserving specific applications of the technology for government needs, and
rollout in the first commercial products in 2010.
A metacloak™ monopole antenna prototype is now shown as an heuristic
on the www.metacloak.net website, with other examples and a white paper to
follow. An educational video on the new fractal metamaterial technology,
including the world’s first wideband invisibility cloak, is being produced
firm for a late-Fall release.