Re: ~e; invisible antenna design

From "H S" <>
Date Sun, 10 Mar 2002 14:43:05 +0100
References <a05101404b8aff7cbeec5@[]>


Prevent Nanotech-based Terrorism

In one of his weekly columns on technology and public 
policy for _Tech Central Station_, University of Tennessee 
law professor and Director Glenn Reynolds 
stated that 2001 "was the year that people started  to get 
serious about the promises and dangers of nanotechnology".  
And he concludes: "Where this powerful technology is 
concerned, a nanogram of prevention is worth a kilogram
of cure. Let's start thinking about  nanoterrorism now, while 
we have the luxury of time. It's a luxury that won't last forever."

----- Original Message ----- 
From: "bc" <>
To: "~e-list" <>
Sent: Saturday, March 09, 2002 6:44 PM
Subject: ~e; invisible antenna design

>   [antenna design has been a curiousity ever since seeing an
>   early manual on the old metal TV antennas were all about
>   the place, pre-cable TV era. the materials and geometry
>   were the reason for the aesthetic design of the antenna,
>   directly correlating with how to maximize picking-up the
>   radio and tv signals from the aether. in the past year or
>   two there have been some advances in this regard. one
>   was a military one, if remembering correctly, that could
>   be sprayed onto a tarp or tent or car window in a certain
>   pattern and be used as a ultra-thin, almost paint-based it
>   seemed, antenna. that was that. the other clue that things
>   may be changing due to materials is the article below, and
>   news about plastics being able to do some things that have
>   been done with metals previously. thus, the geometries of
>   metal that made the skeleton-like antennas often seen ontop
>   of roofs, now because of a change in material may also have
>   a change in form. one guess is that these may be reception
>   antennae, not transmitters. but then again, if in a cell-phone
>   these newer antennas must have some formal shape that is
>   capable of sending a directed signal. one downside, and this
>   is all speculation of course, is that issues with the older
>   cellphone antennas which dealt with the cancer-debate issue
>   would seem to be tougher if the antenna was now in the phone
>   itself, not above the phone (near scalp) but instead by human
>   cheekbones and whatnot. with electromagnetic radiation there.
>   but it is to be debated, but for some reason, the 'invisibility'
>   of the antenna is somewhat scary, as it can make these things,
>   these devices, even more mysterious in their workings, and
>   more of a black-box/magical device. so that one cannot 'see'
>   that it may have more complex effects than plastic phones
>   and their hi-techno designs might suggest via industrial styling.]
> March 7, 2002 WHAT'S NEXT
> Shrinking and Rethinking the Old Vertical Antenna
> Sign up to receive a free weekly Circuits newsletter by e-mail, with 
> technology news and tips and exclusive commentary by David Pogue, the 
> State of the Art columnist.
> As cellphones start to approach the size of matchboxes, their 
> antennas are shrinking, too. In the tiniest new phones the antenna is 
> often hidden inside, where it may take the form of a piece of foil or 
> a coiled wire. But a new material may allow antennas for phones and 
> other devices to become both obvious and invisible at the same time.
> The material was invented by Tom A. Aisenbrey, general manager at 
> Integral Technologies (news/quote), a tiny company with offices in 
> Bellingham, Wash., and Vancouver, British Columbia. While working on 
> a more traditional antenna, he stumbled across a way to mix a 
> metallic compound with plastic or rubber to make a conductive 
> material that can be molded into any shape. That makes it possible to 
> create phones in which the plastic case serves as the antenna.
> Because the material is such an effective conductor, it reduces the 
> amount of battery power needed to send a signal and offers better 
> reception than a traditional antenna, Integral says.
> Mr. Aisenbrey has been trying out prototype antennas on his own 
> cellphone for months. He said that the antenna he is now using is a 
> careful blend of silicone and his metallic compound, the ingredients 
> of which are a company secret. The silicone casing makes a good shock 
> absorber if the phone is dropped, he said, and the antenna can pull 
> in a signal even in deep valleys where reception may ordinarily be 
> poor. Integral says that the manufacturing costs of the new antennas 
> will be the same as or less than those of traditional metal ones.
> Lothar Schmidt, a technical manager at Cetecom, a company that was 
> hired by Integral to assess the antenna, said tests had shown that in 
> some cases the new antenna more than doubled a cellphone's outgoing 
> signal strength.
> Integral is working with GE Plastics to help it develop and market 
> the material, and the two companies are talking to several cellphone 
> makers about using it in their products, said William Robinson, 
> Integral's chief executive.
> Of course, there are other gadgets that could benefit from better 
> antennas, like those that make use of the short-range wireless 
> standard Bluetooth and the Global Positioning System, the satellite 
> network that allows users to plot precise locations. Integral is even 
> talking to a provider of satellite tracking services about turning 
> truck bumpers into giant antennas by making them out of a rubbery 
> blend of the new material. The antennas would improve communication 
> with low-orbit satellites that allow the company to report the 
> location of a truck and status information back to its clients.
> The bumpers will need some exposure to the open sky to communicate 
> with the satellites. But unlike a cellphone network, the tracking 
> system does not need to remain in constant contact to do its job, so 
> it is not a crisis if the signal is temporarily blocked by tunnels or 
> buildings.
> Mr. Robinson said that Integral also planned to make flat antenna 
> strips that could be attached to the sides of shipping containers so 
> that they could be tracked the same way. The strips will be an 
> improvement over standard metal antennas, which are often targets for 
> vandals or are accidentally broken off, he said.
> Mr. Aisenbrey said that the same principle could be applied to cars, 
> where "you could turn the gasket of your windshield into an antenna." 
> Or manufacturers could build an antenna into the surface of a boat's 
> deck.
> The United States military has taken a similar approach by building 
> metal antennas into the structural frame of airplanes. SkyCross, a 
> company based in Melbourne, Fla., that has developed commercial 
> applications for some military communications technology, is working 
> to apply the concept to cars and perhaps buildings.
> When the antenna is structurally embedded in a car, it becomes "a 
> very effective radiator" of electromagnetic waves, said Alan L. 
> Haase, chief executive of Skycross. An antenna built into the walls 
> of a building could do the same thing, he said.
> Skycross is also looking at technology that would allow it to "print" 
> an antenna on the inside of a cellphone's case, Mr. Haase said.
> Integral's invention shows that plastic, hardly a cutting-edge 
> material, still has plenty of untapped high-tech potential.
> Researchers have devoted much attention lately to conductive 
> plastics, which, unlike Integral's material, do not require any metal 
> to make them effective carriers of electric current. The technology 
> is already being used to create moldable plastic batteries for 
> electronic products. For example, NEC released a laptop last year 
> with a lithium-polymer battery wrapped around the back of its screen.
> Blends of plastic and metal compounds similar to the one in 
> Integral's antenna are often found in military equipment, where they 
> act as shielding material to keep enemy sensors from spotting sources 
> of electromagnetic energy. They can also shield people from energy 
> sources in computers and other devices.
> Mr. Aisenbrey said that Integral's innovation was to tweak the blend 
> to make it conductive enough for use as an antenna - in effect, 
> turning a barricade into a pathway.
> Experts on antenna design said that Integral's technology sounded 
> interesting but that they would need more information to evaluate it. 
> They noted that other researchers were also looking to novel 
> materials as a way to boost antenna performance.
> Dr. David M. Pozar, professor of electrical and computer engineering 
> at the University of Massachusetts and a researcher in the school's 
> Antenna Laboratory, questioned Integral's emphasis on seeking to 
> patent its technology.
> "Patents in the antenna area, by themselves, do not ensure the 
> success of a product, and it is usually very easy to circumvent 
> patents" in this field, Dr. Pozar said. Performance and price rather 
> than patents are the keys to success, he added.
> NYTimes online copyright 2002. { fair-use, 2oo2}
>   the electronetwork-list
>   electromagnetism / infrastructure / civilization

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