Metamaterial Radar May Improve Car and Drone Vision

(Source: technologyreview.com)  

Plenty of people play with small drone aircraft in their backyards these days. Tom Driscoll, cofounder and chief technology officer of a startup called Echodyne may be the only one whose quadcopter packs the kind of sophisticated radar used on fighter jets. “We flew it around, did some collision avoidance, and locked onto one of our engineers and followed him around my backyard,” says Driscoll.

Radar instruments that can be used that way are normally bulky and extremely expensive. Echodyne is working on a device that is compact and cheap enough to be used widely.

Radar systems work by sending out radio waves and using the echoes that bounce back to create an image of an object. Some radar systems use electronics to actively steer their outgoing radio waves, instead of just mechanically sweeping a beam in a fixed pattern. This lets them simultaneously scan the sky for objects and track specific ones with high accuracy. But the complex devices normally needed to steer radio waves around, known as phase shifters, make such electronically scanning radar expensive and bulky.

Driscoll’s drone carries an electronically scanning radar instrument that doesn’t have a conventional phase shifter. The outgoing radio waves are steered with a much simpler device, built using techniques borrowed from a relatively new area of research on what are known as metamaterials.

Metamaterials provide a way to get around many of the physical limitations that have previously defined how engineers could control radio, light, and sound waves. For example, while conventional lenses need their characteristic shape to bend light rays into focus, a metamaterial lens can bend light the same way while being perfectly flat.

Metamaterials are made from repeating structures that are smaller than the wavelength of the electromagnetic radiation being manipulated. Echodyne makes its metamaterials by tracing out repeating patterns of copper wiring on an ordinary circuit board.

A board with multiple layers of such wiring can direct radar beams. And applying different voltages to some parts of the wiring makes it possible to actively control the beam as a phase shifter would. “Any printed circuit board manufacturer could produce these,” says Driscoll.

The radar systems used by the military typically start at around $100,000, says Eben Frankenberg, CEO and another cofounder of Echodyne. He says his company hopes to mass produce compact radar systems that cost only hundreds or thousands of dollars.

Continue Reading at technologyreview.com…