US10104501B2, filed by Elliptic Laboratories AS

This patent describes a method for detecting when two devices—such as a smartphone and an appliance—are physically close to each other, using ultrasonic signals. When proximity is confirmed, the system can trigger a relevant action, such as a notification or automatic pairing.

The core innovation lies in using ultrasound to measure actual physical distance between devices, rather than relying on radio signals like Bluetooth or Wi-Fi. Ultrasound has a short and controllable range, and it does not pass through walls, making it well-suited for detecting whether two devices are in the same room. This adds a layer of context-awareness to connected devices in the home or office.

The system can be used to simplify user interactions in the “Internet of Things.” For example, when a smartphone comes close to a smart TV or speaker, the phone can automatically receive a prompt to control it, without the user needing to search for the correct app. The interaction can be triggered by a simple gesture, such as moving the phone toward the device.

This approach reduces friction in smart environments and enhances security by ensuring that actions are only triggered when the user is physically near the intended device. It also opens the door for intuitive, touchless user experiences based on proximity and motion.