Xiaomi's wireless tech promises to charge a smartphone across a room
Chinese smartphone giant Xiaomi has introduced new Mi Air Charge technology that it says can power up your smartphone from across the room – as soon as you walk into a room with the system installed, your handset battery level starts rising.
It's worth noting that this kind of tech has been in the pipeline for years now, and no one has yet brought it to market, but Xiaomi's demo looks intriguing. Xiaomi says wireless room-scale charging is now "closer to reality" with its new system, so you're not going to be able to rush out and buy it just yet.
The Mi Air Charge box that Xiaomi has shown off looks like a small coffee table. Inside there are five phase interference antennas, which are tasked with locating your smartphone in the room. A phase control array made up of another 144 antennas then sends millimeter-wide waves to the phone.
This is done through a technique called beamforming, a way of directing wireless signals towards a specific device, rather than scattering them in all directions around a room. The current incarnation of the tech offers 5-W charging over a range of a few meters, and can work through other objects (like your living room sofa).
The receiving phone also needs the right components built in for all this to work: a beacon antenna to broadcast the phone's position, and a receiving antenna array made up of 14 separate antennas to convert the millimeter-wave signal into energy that the phone's battery can then use.
What's more, the futuristic-looking box can wirelessly charge up multiple devices at the same time. Further down the line, Xiaomi says that the batteries in our gadgets will be kept topped up all the time while we're in particular rooms – smartwatches, speakers, desk lamps and other smart home products can all benefit.
Xiaomi hasn't said exactly when the Mi Air Charge system is going to be available, or how much it will cost, and questions remain about exactly how it's going to work in practice. For now the company says it's at the "tech demo" stage and won't reach consumers before 2022 at the earliest.
That said, it looks as though the hardware is already working to some extent, and Xiaomi has a strong enough track record in fast-charging and wireless-charging technology to suggest that it might be able to pull this off eventually. You can see the promotional video Xiaomi has put together about Mi Air Charge below.