Why wireless charging must be put on the charging board

Wireless charging is nothing new, but as the new iPhone begins to support this feature, its exposure will increase dramatically. However, wireless charging technology is still subject to many limitations, especially the charging range. In most cases, "wireless charger" is not literally wireless. Users must contact the device with the charging board. If you take the phone off the charging board for a centimeter, the charging will stop.

A company called PI wants to change the situation of "wireless charging is not wireless". They are developing a device called PI charger that can charge multiple devices within a radius of about 30 cm. This is not a concept that other companies have been trying to implement for many years, but PI provides more flexibility than a single charging board.

The PI team said they used resonance induction, the underlying technology of the wireless charging standard Qi adopted by the iPhone 8 / X and many Android phones. According to the company's co-founder, John MacDonald, their secret is a beamforming algorithm that allows them to safely direct the magnetic field to where the device is located.

"The core is this algorithm, which allows us to shape a magnetic field." John told me, "it's an old idea But our behind the scenes genius, my co-founder Lixin Shi, has managed to solve the complex problems. That's a very complicated problem. It will take you a few minutes to work out with the latest i7 processor. His model proves that we can get the best solution through two clock cycles on a simple microcontroller. "

PI showed us the process of charging. They put five devices (four mobile phones and one tablet) in the effective range of PI charger and charged them at the same time.

So why is it called "Pi"? This is a tribute to the two co founders' alma mater: MIT. The Institute celebrates PI (π) in a variety of ways, including issuing admission notices on Pi Day (March 14 every year); considering that the program was hatched by a lab at MIT, it seems reasonable to continue this tradition.

The company's life comes from the computer science and Artificial Intelligence Laboratory (CSAIL) of MIT. The two co founders of the company met accidentally in an entrepreneurship class (both of them were urged by their classmates and teachers). They decided to reach an agreement with the school to turn Shi Lixin's research results into a business project.

"Without this school, we would not exist." Said John. The company has raised $3.5 million so far. The PI team said they haven't priced their chargers yet, but they expect to launch the product for less than $200 sometime in 2018.