DTA staff wrote these assessments of Bluetooth technology for contact tracing in the first six months of 2020.
A Summary of Bluetooth Low Energy [PDF, 614 KB]
Bluetooth Low Energy (BLE) is a low power evolution of the Bluetooth personal area network standard capable of power efficient short-range wireless communication. BLE chipsets are now commonplace in consumer electronic devices facilitating connectivity to a multitude of wireless sensors and wearables. A key driver in this market is the BLE Advertisement which allows small packets of data to be passed easily between devices. This paper explores the technology behind Bluetooth, BLE and the concept of an Advertisement.
Bluetooth Proximity Estimation by Signal Strength [PDF, 330 KB]
Bluetooth-based proximity apps are currently of intense interest as an enhancement to manual contact tracing for controlling COVID-19. This report discusses the accuracy of distance estimation that can be achieved using Bluetooth proximity apps, and highlights potential problems based on the known characteristics of Bluetooth radio signals. It does not discuss the details of currently available implementations or data handling and privacy issues, which are still rapidly evolving at the time of writing.
Summary of Bluetooth Contact Tracing Options [PDF, 154 KB]
Bluetooth-augmented contact tracing has emerged as a novel system for health authorities to use during the ongoing COVID-19 pandemic and is recommended for use as part of an audit of contact tracing by infectious disease specialist Dr Ayesha Verrall. Each Bluetooth contact tracing protocol has a trade-off between important factors such as privacy, performance and the health authority’s access to interaction data. This paper reviews the rapidly evolving landscape of approaches that have emerged at the time of writing, with a focus on identifying the best candidates for use within New Zealand.