Acoustic distance measurement device and system KU Leuven
The invention relates to a technique providing high precision in hybrid RF and audio system, while enabling ultra low power, by means of sending the ultrasonic waves ahead in anticipation of an RF-based wake-up signal. Herewith, the low power nodes are kept awake for a considerable time. The invention further relates to hybrid distance measurements approached from a different perspective in comparison with the art, and thus now being well suited for energy-constrained nodes. An RF signal is used for synchronisation, whereas the distance measurements are merely based on acoustic chirps.