Google’s Advanced Technologies and Projects (ATAP) group has been granted a waiver by the Federal Communications Commission (FCC) that will permit the company to test their Project Soli sensors at the 57-64 GHz bands at a radiated power of +13dB, with an additional provision that the sensors can be operated onboard aircraft.
This waiver is significant because it will allow Google to take the next step in making their radar-based touch interface technology a reality.
The Soli chip. Image from Google ATAP
Project Soli was first announced in 2016 at the Google I/O conference, presented as a dime-sized, 8mmx10mm, radar chip. Once integrated into a device such as a smartwatch or phone, the chip can provide a realistic, tactile, three-dimensional feedback interface seemingly out of thin air and at high resolution (0.3mm).
Gesture recognition is key to Project Soli's novelty. Pushing your fingers together can imitate a button press, pinching a dial and rotation can scroll through a menu, and multiple other innovative gestures and motion tracking.
The Soli concept. Image courtesy of Google ATAP.
However, FCC regulations on short-range interactive motion sensing devices limited the maximum power the radar could be operated at, within the +10dB range. The waiver grants Google permission to operate the Soli radar sensors at +13dB, with +10 dB transmitter conducted output power, and further permits the devices to be used onboard aircraft.
What Goes into an FCC Waiver Application?
It is easy to recoil at the words "regulation" and "waiver", especially when followed by "the FCC". One of the FCC’s jobs is to ensure that transmitting devices do not interfere with other transmitting objects, and that it is safely used. When applying for the waiver, Google ATAP had to justify their reason for requiring an increase in transmitting power, demonstrate through simulations and data that this would not cause harmful interference among other devices, and answer any petitions against the waiver from the public.
Google ATAP’s justification is pretty straightforward: the maximum allowable transmission power was limiting the ability of their technology to be useful to the public. They argue that the Soli radar is a useful interface technology that can have especially beneficial impacts and improve quality of life for individuals with mobile, tactile, or speech impairments. Further, the request was in line with the European Telecommunications Standard Institute's (ESTI) regulations.
Operation on Airplanes
Some of the data and simulations Google supplied included the simulation of the device being used in an airport during a peak travel day, suggesting how Soli radar would contribute to interference onboard an aircraft. It was determined that the sensor could be operated safely, even while in flight.
This means that you could see Project Soli-related gesture recognition wearables in the commercial realm soon, even in some of the most tightly-controlled areas of communication.
Facebook Raised Red Flags
The primary concerns petitioned were the potential interference that could be caused by the radar sensors by other entities that operate in the same range. Most notably, Facebook wrote letters of concern over interference with their planned WiGig-based Terragraph network, an Internet service currently under development and possible interference with possible "point-to-point communications between short-range devices (“SRDs”) in the band."
Facebook's Terragraph Network. Image courtesy of Terragraph.
However, in the waiver, it appears as though Google and Facebook had come to an agreement on how these two technologies can co-exist: Google’s initial request was for a +10dB power increase, and that was reduced to + 3dB, which would not interfere with Facebook’s Terragraph network.
Keep an eye out for Project Soli announcements as these radar sensor chips get closer to the mainstream.