Nov 23 2010
Despite promises of amazing features, metamaterials have failed to demonstrate practical applications.
Now researchers at Fractal Antenna Systems have delivered on that promise, showcasing a new video that reveals metamaterials are a valuable application resource, whose advantage is dramatically enhanced using geometric shapes called fractals.
Metamaterials are composites with unique electromagnetic attributes. Fractals are structures built up from repeated sizings of a simple shape to make a complex one. Fractals are used to make partless, shrunken resonators, also called tuned circuits, that are densely and closely packed as a metamaterial, wound as cylinders in this example, then placed on top of a conventional antenna for dramatic performance enhancements.
The new video shows how the fractal metamaterials improve a monopole or ‘vertical’ antenna. With careful scientific protocols and controls, scientists at Fractal Antenna Systems demonstrate how a fractal metamaterial sleeve, with no power or electrical connection to the actual antenna, dramatically increases the bandwidth and gain. The firm’s CEO Nathan Cohen notes: “Some people need to be convinced that metamaterials and fractals are useful tools in the electronic toolbox. We feel the same way, and are happy to oblige with this educational video. It makes an overwhelming case for the fractal advantage, in this case with a specific and fascinating metamaterial application.”
Conservatively describing the bandwidth improvement as tripled, the actual bandwidth increases from 120 MHz to a new value 1500 MHz, just by slipping the fractal metamaterial sleeve over the monopole. Cohen added: “Physicists and engineers define bandwidth in different ways, either through a standing wave ratio or a half power point. We think folks should look for themselves, as any way you define it, it is startling and dramatic.”
The gain of the antenna also undergoes improvement, more than doubling value. Cohen also notes that this is an expected and well understood result. Cohen concluded: ”What is exciting for us is that fractals enable this technology, and as the inventors and patent holders, we are the innovators bringing it to our products and designs, and are happy to show this example to help others understand the benefits.”
Source: http://www.fractenna.com/