Pi’s Wireless Qi Charger Can Charge Phones From A Distance

September 21, 2017 - Written By Mark Real

Pi, a startup formed by researchers from the Massachusetts Institute of Technology (MIT) is developing a charger based on the Qi wireless charging standard, but it’s different than standard Qi wireless chargers, as it can top up compatible devices located up to one foot away. This device, which will be called Pi Charger, is also capable of charging multiple devices at once, which is another limitation of wireless chargers that are currently available. Wireless charging works through the process of induction, more specifically the resonant inductive coupling between the charging station, the sender, and the smartphone, the receiver. Once the device is placed above the sender, it will transmit signals that check the handset’s compatibility and energy requirements. However, researchers are still working to improve wireless charging standards, with some already working on a full-room charging concept.

Current wireless charging solutions require the user to place the devices directly on top of the charger, and some setups will not work if the handsets are placed in a different orientation. Pi charger aims to provide flexibility to consumers by using a beamforming algorithm that directs the magnetic field to smartphones compatible with the Qi wireless charging standard, allowing them to be charged at a distance. Beamforming is a general term for the process that focuses radio or magnetic signals to a single sector, increasing the signal strength and reducing interference. The charging speeds decrease, however, as the smartphone moves away from the Pi charger.  

Developers noted that there are a few key obstacles to the design and construction of the product and one of them is the computational power and time needed to calculate the beamforming algorithm. It previously needed a high-end Intel x86 processor to compute the algorithm, but the people behind the project managed to reduce these requirements to a simple microprocessor. It also seems that the actual product is already in the last stages of the development process, as the startup was able to show off a unit of the charger in a demonstration, where the Pi charger was able to charge five devices at the same time, one of which is a tablet and the rest are smartphones. Other improvements that the startup plans to implement include a component that can be plugged into existing wired devices like the Google Home. The Pi charger will be sold next year for less than $200, but the manufacturer did not identify when exactly will the product be available.