A Stanford University, Stanford, CA, engineering team has built a radio the size of an ant that requires no batteries. The device gathers all the power it needs from the same electromagnetic waves that carry signals to its receiving antenna. Designed to compute, execute, and relay commands, the tiny wireless chip costs pennies to manufacture.

The tiny radio-on-a-chip gathers all the power it needs from the same electromagnetic waves that carry signals to its receiving antenna. (Credit: Amin Arbabian)
Their approach entailed dramatically reducing size and cost entailed squeezing all the electronics found in a typical Bluetooth device down into a single, ant-sized silicon chip.

However, to build a device this tiny, every function in the radio had to be reengineered. The antenna had to be one-tenth the size of a WiFi antenna, and operate at 24 billion cycles per second. The final design fit a receiving antenna that also scavenges energy from incoming electromagnetic waves, a transmitting antenna to broadcast replies and relay signals over short distances, and a central processor to interpret and execute instructions—all on one chip.

For more information, visit www.medicaldesignbriefs.com/component/content/article/1104-mdb/news/20627.