Channel Sounding: Metrological Exploration of the Design Options Using Related Positioning Systems

Bluetooth® channel sounding, which has recently found its way into the first integrated circuits, is a method for accurate distance estimation between Bluetooth® devices using phase-based concepts and time of flight. The aim of this paper is to carry out a metrological exploration to support designers in the identification of suitable algorithms for ranging and positioning. In addition, the inclusion of signal strength, which is often also available for Wi-Fi® in composite chips, is being discussed. The disadvantage of the still young hardware is the long time required to connect two devices. For positioning, a link must be repeatedly established to several base stations of this type, which means that position updates tend to take minutes. Due to this delay, it is not permissible to carry out large measurement campaigns. For this reason, our exploration is based on very similar systems that have comparable properties and mode of operation. Key contributions include a) a concise theory presentation, b) experimental evaluations of different approaches and configurations for ranging, aggregation and positioning, and c) design recommendations for developers to align with specific constraints such as scenario size, environmental conditions, accuracy and costs.