Wireless Sensors That Live Forever

Energy harvesters and radioisotopes fuel tiny transmitters

2 min read

Soon enough, say some engineers, miniature wireless sensors will be located in spots where it would be inconvenient, to say the least, to change their batteries—inside your body, within the steel and concrete of buildings, in the dangerous innards of chemical plants. But today, even the most robust nodes can be counted on to last only a few years. Ideally, engineers need a sensor that can last forever without external power sources or battery changes. According to research presented in December at the International Electron Devices Meeting, in Baltimore, that dream is within reach.

Two research teams tackled the problem of sensor longevity in two very different ways. Both methods rely on piezoelectric power generation, in which a microelectromechanical systems (MEMS) cantilever converts mechanical motions into electrical power. However, the cantilever's movements are propelled by very different mechanisms—one by a radioisotope and the other by vibrations harvested from the environment. In a big step forward, both methods fully powered autonomous wireless systems.

Keep Reading ↓Show less

This article is for IEEE members only. Join IEEE to access our full archive.

Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, podcasts, and special reports. Learn more →

If you're already an IEEE member, please sign in to continue reading.

Membership includes:

  • Get unlimited access to IEEE Spectrum content
  • Follow your favorite topics to create a personalized feed of IEEE Spectrum content
  • Save Spectrum articles to read later
  • Network with other technology professionals
  • Establish a professional profile
  • Create a group to share and collaborate on projects
  • Discover IEEE events and activities
  • Join and participate in discussions

The Transistor of 2047: Expert Predictions

What will the device be like on its 100th anniversary?

4 min read
Six men and a woman smiling.

The luminaries who dared predict the future of the transistor for IEEE Spectrum include: [clockwise from left] Gabriel Loh, Sri Samavedam, Sayeef Salahuddin, Richard Schultz, Suman Datta, Tsu-Jae King Liu, and H.-S. Philip Wong.


The 100th anniversary of the invention of the transistor will happen in 2047. What will transistors be like then? Will they even be the critical computing element they are today? IEEE Spectrum asked experts from around the world for their predictions.

Keep Reading ↓Show less