Apple and Samsung have been quietly contributing to a new technology to find and seamlessly unlock your car with your phone, without pulling a fob out of your pocket — and Tesla may be one of the first with the tech. Tesla is actively working on building UWB into its cars, according to documents filed with the Federal Communications Commission.

On September 9th, the company submitted six new “products” for the FCC’s consideration, including two key fobs, a security controller, and a number of “endpoints” that would be installed inside the frame and cabin of a vehicle:

According to the FCC documents, at least three of those products explicitly support UWB communication.

What’s more, Tesla’s FCC filing is unusual in that it includes a complete operational description of the technology, something that’s usually redacted. The highlights: it’s a standards-based implementation of UWB, which means UWB phones from Apple and Samsung should theoretically be compatible, and it’s designed to let you know how far away you are from the car.

That’s helpful to avoid replay attacks that try to trick your car into thinking its key fob is closer than it actually is. But it also theoretically unlocks the ability to find your car in a crowded parking lot using your phone.

When I spoke to UWB chip supplier NXP last year, company CTO Lars Reger told me that future cars would likely need several of these UWB endpoints inside the car, possibly at the door handles, to properly triangulate your location and know whether you’re inside or outside so, say, your kids won’t be able to turn on the engine if you’re not actually in the cabin. Apparently, Tesla thinks the B-pillars and a piece of fascia might be good places to put those antennas, too.

None of this means that Tesla will necessarily add the tech to its cars, but FCC documents are usually a pretty good sign that it’s not just an experiment. FCC filings are typically one of the last waypoints before a product comes to market, as they’re only required if you’re going to import, sell, or do widespread testing of a radio product in the US.

Last we checked, BMW was the only other automaker that’s committed to UWB.