The concept described in the title might be a little hard to digest. Mainly because a lot of people think about potential health hazards when they think about wireless power, but the Ossia Cota Tile is safe to use. It uses targeted radio waves to charge multiple devices within a 30 ft radius.
Let’s get a bit technical for a moment to explain why Cota is safe and just works. There are, traditionally, four main ways of transmitting wireless power:
- Tesla Coils (Dangerous)
- Radio waves
- Inductive Coupling
Out of these four, the only three viable options are Lasers, Radio waves, and Inductive Coupling.
Wireless charging using inductive coupling is already available. But it isn’t wireless in an actual sense. It uses charging pads that need to be connected to a power supply with a cable and the device needs to be on the charging pad.
Lasers can be efficient, but the directivity is an issue because the device will need to be completely in line with the transmitter.
Radio waves have a long-range. But due to a law, known as ‘inverse square law’, the strength drops as the inverse square of the distance. This reduces efficiency. But in an interview with iTWire, Ossia’s Abid Hussain – who lead the Qualcomm team that developed QuickCharge which is present in a lot of modern smartphones- explained that Ossia uses technology that uses low-power radio waves and converges it into high power RF at the desired point.
How does the Cota Tile work to provide wireless charging?
A minuscule receiver embedded in a device pings the power transmitter (Cota Tile) at 100Hz. Which means that it sends out a message 100 times each second. Almost instantly, it then sends a data packet to the Tile enlisting its current charge status. The transmitter consists of thousands of omnidirectional antennas that beam RF waves over 2.8GHz, so they are safe and won’t interfere with Bluetooth and WiFi signals.
The signal is transmitted in the direction of the transceiver with sub-millimeter accuracy. The RF signal is rectified to DC power by the embedded receiver. Currently, the power received is 1 watt per 8 watts required to transmit it. That does not sound very efficient, but the Ossia team is working on increasing that ratio. Another key point to be noted is that multiple devices can be charged simultaneously.
To operate within the FCC’s (Federal Communications Commission’s) safety standards the rate of power transmission is one-third to one-fifth of standard USB charge speed. But according to the founder of Ossia, this won’t be an issue.
Ossia is undergoing a third round of testing at an FCC lab and is confident of meeting all SAR requirements. With nine patents and five generations of the Cota under its record, Ossia can change the future of chargeable devices.
Watch this video explaining another Ossia device which works on the same principle.