Researchers turn 5G networks into wireless power grids for IoT

Researchers from the Georgia Institute of Technology have come up with a novel method of tapping into the over-capacity of 5G mobile networks. The new technique turns the 5G network into a wireless power grid able to power small Internet of Things (IoT) devices that currently require batteries to operate. In many of these small devices, the battery prevents the miniaturization of the devices to smaller scales.

Georgia Tech researchers developed a flexible Rotman lens-based rectifying antenna system capable of harvesting millimeter-wave in the 28 gigahertz band for the first time. A Rotman lens is critical for beamforming networks and is typically used in radar surveillance systems for viewing targets in multiple directions without physically moving the antenna. To create the system able to harvest enough power to run low-power devices at long ranges, larger aperture antennas are required.

The challenge with larger aperture antennas is that they have a narrow field of view, limiting their operation if the antenna is widely dispersed from the 5G base station. Project researchers solved that problem by looking from only one direction with a system that has a wide-angle of coverage. The team says that current 5G networks were built for high-bandwidth communication. The high-frequency network holds an opportunity to harvest unused power that would otherwise be wasted.

Researcher Jimmy Hester says the innovation will allow large antennas to work at higher frequencies and receive power from any direction. Its ability to be direction-agnostic makes the solution "a lot more practical." All of the energy collected by the antenna array from one direction is combined and fed into a single rectifier to maximize efficiency. The technology created by Georgia Tech has achieved a 21-fold increase in harvesting power compared to other counterparts while maintaining identical angular coverage.

Researchers created the devices using in-house additive manufacturing to print palm-sized millimeterwave harvesters on a multitude of everyday flexible and rigid substrates. Someday the technology can replace batteries with over-the-air charging, which could revolutionize electronics of all sorts.