Metamaterial identifies source of radio waves

The technique could lead to inexpensive devices that can find radio wave devices like cellular phones or Wi-Fi emitters, or cameras that capture images using radio waves. Their results appear online in Optica.

UK team sounds off with metamaterial bricks

"In this paper we achieved spectral images of microwave noise sources themselves, which means we can locate radio and microwave sources, like antennas, while simultaneously characterising what frequencies they are emitting over," said Aaron Diebold, an electrical and computer engineering research assistant at Duke University, North Carolina, who led the research. "At optical frequencies, that would be like getting a colour image of a hot object like a stove burner. While that is pretty simple optically, it takes different techniques in the radio and microwave regime."

Locating sources of these types of waves is already possible, but the techniques and equipment required are complex. Such devices traditionally use an array of antennae that cause them to become bulky and expensive. According to Duke, radio waves are much larger than light waves, so the methods used in optical frequencies are prohibitively complex and would result in extremely large detectors and other machinery.