SHORT RANGE POSITONING USING ULTRASOUND TECHNIQUES

Positioning techniques are a strong enabler for various innovative services, often related to the Internet of Things paradigms, that include for instance Domotics, Ambient Assisted Living, and Line Traceability. Ultrasound transmissions enable low cost and accurate solutions, competitive in Line of Sight and short-range scenarios with respect to other technologies, such as those based on image processing or on transmissions of EM signals. Ranging and positioning is usually achieved using time domain measurements, such as Time of Flight, Round Trip Time, or Time Difference of Arrival (TDoA). The latter solution is interesting and explored in the described activity, since it does not require synchronization of the involved nodes. Moreover, current embedded and sensor technologies consent to easily generate, acquire, and process ultrasound signals, coupling transducers to low-cost embedded platforms. In a previous activity, a simple positioning 2D system was proposed, based on TDoA measurement performed by wireless capable nodes [1]. In this activity, the system performance was studied, as a function of the data acquisition sampling frequency and resolution. Performance improvement was assessed, by comparing the achieved timing and ranging accuracies.