Apple has been granted a patent (number 10,024,876) for “pedestrian velocity estimation.” It involves the tech that allows your Apple Watch to tell you how fast you’re moving.
In the patent info, notes that mobile devices are often used with fitness applications for monitoring and tracking fitness-related metrics such as distance walked or run, calorie consumption, and heartbeat. Some mobile devices use velocity data provided by a GNSS receiver that is embedded in or coupled to the mobile device to determine the velocity of a pedestrian user.
Power efficient GNSS receivers often run within a short-dwell GNSS power optimization (SDGP) mode. For example, for every second of operation a GNSS receiver may run in full power mode while dwelling on satellite signals (e.g., 200 ms) and then switch to a low power mode for the remaining time (e.g., 800 ms). The difference in power consumption by the mobile device can be significant. The impact of SDGP, however, can lead to errors in the estimate of GNSS velocity. Apple’s goal is/was to fix this.
Here’s Apple’ summary of the invention: “Systems, methods and computer-readable mediums are disclosed for GNSS velocity estimation for pedestrians. In some implementations, a method includes receiving a periodic sensor signal; determining a fundamental motion frequency of the periodic sensor signal; extracting a periodicity feature from the periodic sensor signal based on the fundamental motion frequency; and responsive to the extracting, initiating pedestrian velocity estimation.”
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.