Demo: Eavesdropping on PolyPoint: Scaling High-Precision UWB Indoor Localization.

Recently, we introduced PolyPoint, a high-fidelity RFbased indoor localization system that achieves 28 cm accuracy indoors and tracks a fast-moving quadcopter with only 56 cm average error. PolyPoint uses ultra-wideband signals to achieve high precision RF time-of-flight estimates between nodes. To further improve accuracy, PolyPoint exploits two forms of diversity: frequency diversity, which leverages several ultra-wideband channels to improve channel response, and antenna diversity, which adds three antennas at 120° offsets to mitigate the effects of antenna polarization and nulls. To efficiently capture this diversity, PolyPoint introduces an efficient, novel ranging protocol that maximizes these diversity sources with a minimal number of packets. Unfortunately, this protocol can only locate one tag concurrently. In this demo, we explore whether passive, eavesdropping tags can also glean location information, albeit at lower fidelity. Additionally, we demo our hardware platform that provides ranging and localization as a drop-in module. The minimal TriPoint integrates an ultra-wideband transceiver and microcontroller with firmware that implements the PolyPoint protocol. The TriTag carrier board adds Bluetooth and batteries to create a complete mobile tag, and the TriBase anchor platform integrates a TriPoint with an Intel Edison to act as anchors for the system.