Mesh network technology could provide a key capability for contact tracing apps that are currently being developed.
Developer Wyld Networks is talking to the UK’s NHS about how Bluetooth technology can be included in these applications that will be able to flag if a user comes within a few metres of someone with the Covid-19 virus.
Apple and Google are currently developing a common API for Bluetooth that works across both iPhone and Android smartphones. This will be available by the middle of May, say the companies.
The applications will create a timeline of people coming into contact with COVID-19 patients by using masked personal identifiers and recording the time they are in close proximity. To work, the apps will require a significant percentage of a country’s population to voluntarily install them and to be most effective, they should also be cross-border solutions. In Europe, the EU’s privacy watchdog has already called for a single pan-EU app.
Early versions of the apps are currently using Bluetooth Low Energy (BLE) and Received Signal Strength Indicator (RSSI) technology for proximity tracking. However, experience has shown that potential limitations in BLE can lead to inaccuracies in locating a smartphone on a person that may have been in contact within two metres for 15 minutes, says Wyld.
As more people use the app, the continuous polling methodology in standard BLE could lead to some people not being registered. And in some situations, several sub-networks could be created, causing more than one person to have inaccurate registrations in their zone.
Mesh network technology can enhance BLE and improve the accuracy of locating people within the proximity zone. One of the concepts of the mesh technology is multi-hop, which can create a very robust network of phone-to-phone connectivity to significantly increase the probability of making connections with everyone in a proximity zone.
One of the other issues in early contact tracing applications is the reliance on