The wireless power grid that can power your car, phone, connected appliances and more is still the stuff of science fiction, and despite advances from Ossia, Energous, Xiaomi and Motorola, there's still no wireless power systems available to power your devices in the same way that Wi-Fi delivers the Internet to your smartphone, tablet, computer and other technologies.
However, IoT devices usually require far less power than traditional portable devices or appliances, and given that mmWave 5G is sending out a lot of power, if this could be reliably harvested, you can power your devices from the 5G mmWave frequencies that are already available in many places, and which is only being more widely rolled out with every passing day.
Over at Nature Magazine, the Georgia Tech scientists issued a paper that explains it all.
In the abstract, the authors state: "5G has been designed for blazing fast and low-latency communications. To do so, mm-wave frequencies were adopted and allowed unprecedentedly high radiated power densities by the FCC.
"Unknowingly, the architects of 5G have, thereby, created a wireless power grid capable of powering devices at ranges far exceeding the capabilities of any existing technologies. However, this potential could only be realised if a fundamental trade-off in wireless energy harvesting could be circumvented.
"Here, we propose a solution that breaks the usual paradigm, imprisoned in the trade-off between "rectenna" angular coverage and turn-on sensitivity. The concept relies on the implementation of a Rotman lens between the antennas and the rectifiers.
"The printed, flexible mm-wave lens allows robust and bending-resilient operation over more than 20 GHz of gain and angular bandwidths.
"Antenna sub-arrays, rectifiers and DC combiners are then added to the structure to demonstrate its combination of large angular coverage and turn-on sensitivity—in both planar and bent conditions—and a harvesting ability up to a distance of 2.83 m in its current configuration and exceeding 180 m using state-of-the-art rectifiers enabling the harvesting of several μW of DC power (around 6 μW at 180 m with 75 dBm EIRP)."
So, the beginnings of a wireless power grid delivered via 5G signals is something we'll hopefully see this decade, along with a range of other wireless power technologies that will reduce the need for batteries in many settings.
Of course, until we can harvest power from satellite broadcasts, or from zero-point energy devices, or from geothermal technologies, or thorium reactors, or something else that can be widely distributed, batteries will always be essential.
Still, it is within most of the lifetimes of anyone reading that true wireless power should become as natural as Wi-Fi is today, as humanity finds ever better ways to generate and distribute power, be it via wired or wireless means.