If I were a battery, I might wonder what I did wrong and why teams of scientists around the world are working hard to do away with me. Engineers developing technology that harvests energy from magnetism, body heat, yarn, the human knee, water, and even bacteria all seek to reduce the reliance on batteries in wearables, mobile devices, and implants. It’s draining to even consider how the need for periodic recharging or replacement could relegate batteries to sit on the bench while energy-harvesting tech starts and plays every inning.
So here’s another form of energy harvesting: capturing 5G network energy to replace millions of batteries in wireless sensors. Georgia Institute of Technology engineers in the School of Electrical and Computer Engineering published a report on their innovative work in Scientific Reports. In “5G as a wireless power grid,” the Georgia Tech engineers describe their antenna development.
The key to the researchers’ advance is a Rotman lens-based rectifying antenna (rectenna) that can harvest millimeter wave energy in the relatively high frequency 28-GHz band. The technology is direction-agnostic, meaning it can receive power from any direction. Their design overcomes the traditional large aperture Rotman lens antenna designs limited by a narrow field of view. The Georgia Tech antenna harvested 21 times as much power as a standard design.
To further demonstrate the potential impact of their design for wearables and a wide range of IoT applications, the Georgia Tech team 3-D printed and inkjet printed smaller, palm-sized versions of the antenna on various rigid surfaces.
As 5G networks spread, energy harvested essentially “out of the air” could be used to power sensors for crop managment, vehicle tracking, biometric sensing, and hordes of other IoT devices. This may not mean the end of batteries, but certainly could reduce the demand for them. If power is everywhere, current tech batteries could gradually move from the bench to the shelf and finally to a cold dark cell.
