A radio antenna less than one-tenth of an inch long sits on a computer chip and can send and receive signals across a room. University of Florida electrical engineers devised the device as a step toward building an ultrasmall radio chip — a transceiver, processor, and battery all on a chip not much larger than a pinhead.

The goal is to pair radios with equally tiny, inexpensive sensors as a way of saturating large areas with sensing and communication capabilities. For example, airplanes could drop radio-motion detectors by the hundreds of thousands along boarders, creating an electronic eavesdropping "fence" that would alert authorities to anyone illegally crossing the border.

Other applications may include using the tiny radio "nodes" in place of heavy wiring in aircraft and spacecraft, as a way of lightening these crafts. However, the most important factor in the latest research is that it gets the antenna on the same chip as the radio circuits. "The problem of getting RF from an antenna through wires to a chip has always been difficult, and the latest research eliminates an interface," says Joe Brewer, a UF electrical and computer engineering professor.