Apple has filed for a patent (number 10,051,423) for “time of flight estimation using a convolutional neural network.” Despite the title of the patent, it’s intended to make it easier to find a lost or misplaced iPhone or iPad.
In the patent filing, Apple notes that devices that implement wireless communication technologies are commonly mobile or portable. The tech giant notes that it’s often useful to estimate the position or location of such devices.
For example, it may be helpful to be able to determine the location of a device that has been separated from its user or lost. It may also be desirable to estimate the position of a device for map applications, Internet search applications, social networking applications, targeted advertising, determining locations of available services such as printers, etc.
In current systems, Apple says position estimation is typically performed using GPS (Global Positioning System) technology (or GLONASS technology), which is integrated into the mobile device. However, alternative Wi-Fi-based positioning systems may be used wherein technologies like GPS and GLONASS perform poorly, e.g., when the mobile device experiences multipath issues or suffers from signal blockage due to being indoors.
Some Wi-Fi-based positioning systems use time-of-flight estimation to determine the distance and position of a mobile device relative to another device, such as another mobile device or a Wi-Fi access point. Apple says “improvements in the field are desired”; hence, the patent filing.
Heres Apple’s summary of the patent (be warned: it’s heavy on tech-speak): "Embodiments herein relate to using a convolutional neural network (CNN) for time-of-flight estimation in a wireless communication system. A wireless device may receive, from a remote device, wireless communications including a first transmission time value associated with the transmission of the wireless communications.
“The wireless device may perform a coarse time-of-arrival (TOA) estimation on the wireless communications received from the remote device. The coarse TOA estimation may be used to generate an estimated impulse response, which may be input to a CNN associated with the wireless device to calculate a line-of-sight estimate. The wireless device may determine a range between the wireless device and the remote device based on the transmission time value and the line-of-sight estimate.”
Of course, Apple files for — and is granted — lots of patents by the U.S. Patent & Trademark Office. Many are for inventions that never see the light of day. However, you never can tell which ones will materialize in a real product.