Bluetooth LE wearable provides Covid-19 social distancing, contact tracing solution for events


Proximity Monitor developed by Forkbeard Technologies and deployed by EY, employs Nordic nRF52811 and nRF52832 SoCs to monitor proximity data

Nordic Semiconductor today announces that Nordic’s nRF52811 Bluetooth® Low Energy (Bluetooth LE) System-on-Chip (SoC) and nRF52832 Bluetooth LE SoC are being deployed in EY’s ‘Proximity Monitor’ developed by Oslo, Norway-based technology company, Forkbeard Technologies. The social distancing/contact tracing solution has been designed in response to the Covid-19 pandemic. 

Accurate proximity measurement

Proximity Monitor provides relevant authorities with live data on the effectiveness of social distancing measures and awareness communication strategy at specific events. The solution can be worn as a tag on a lanyard, as a wristband, or downloaded as the Android/iOS ‘Proximity Monitor’ app (developed by Forkbeard) for use via a Bluetooth 4.0 (and later) smartphone. Once the tag is activated it effectively creates a ‘Bluetooth Bubble’ around the user enabling the system to accurately monitor their proximity to other attendees at the venue. For example, attendees at a sporting event, or employees in a workplace, can be issued with a tag that once activated monitors proximity in relation to other tags (and smartphones running the companion app) using Forkbeard’s proprietary software and the Nordic SoC-enabled Bluetooth LE connectivity.

Forkbeard developed application code for the Proximity Monitor solution relying on the excellent example code made available by the Nordic Software Development Kit
Wilfred Booij, Forkbeard Technologies

Forkbeard specified the nRF52811 SoC to provide robust and low-latency Bluetooth LE wireless connectivity for EY’s tags running the Forkbeard firmware. The tags are battery powered and work by sending and receiving Bluetooth LE signals from other nearby tags every few seconds. Proximity data between users on a site is relayed to a Cloud/web-based dashboard (developed by EY and built on the SAP Cloud), via the smartphone app or a nRF52832 SoC-powered Minew central gateway. From the Cloud platform a control room can grade the distance from each individual to others as low, medium, or high risk. 

The proximity data is not only used for person-to-person interactions, but also person-to-location interactions. Nordic nRF52832 SoC-powered beacons running the Forkbeard firmware can be employed to augment human proximity data from the tags with location data which is then relayed to the Cloud via a user’s smartphone and/or the central gateway. Using the information gathered by the proximity sensors, facility or event management can manage contact tracing and social distancing protocol adherence. Individuals can also manage personal social distancing via the app. 

The Proximity Monitor tags use lithium coin cell or rechargeable Li-Poly batteries to achieve battery life between one week and three months depending on tag type and configuration, while maintaining a proximity contact monitoring interval of 10 seconds or less. This endurance is possible in part thanks to the ultra-low power characteristics of the Nordic SoC. The nRF52811 SoC has been engineered to minimize power consumption with a fully-automatic power management system that reduces power consumption by up to 80 percent compared with the nRF51 Series. 

Direction Finding support

Nordic’s nRF52811 multiprotocol SoC is a fully-featured connectivity solution that supports Direction Finding, which brings precise positioning capability to the SoC in addition to all the features of Bluetooth 5.2 (including Bluetooth Long Range, 2Mbps raw data bandwidth, and enhanced coexistence capabilities). The nRF52811 combines a 64MHz, 32-bit Arm® Cortex® M4 processor, with a 2.4GHz multiprotocol radio (supporting Direction Finding, Bluetooth 5.2, Thread, Zigbee, IEEE 802.15.4, and proprietary 2.4GHz RF protocol software) featuring 4dBm output power with -97dBm sensitivity (at 1Mbps in Bluetooth 5 mode), and 192kB Flash memory plus 24kB RAM. The nRF52811 SoC is supplied with Nordic’s S112 SoftDevice, a Bluetooth 5-certified RF software protocol stack for building advanced Bluetooth LE applications. The S112 SoftDevice features Central, Peripheral, Broadcaster and Observer Bluetooth LE roles, supports up to four connections, and enables concurrent role operation. 

Nordic’s nRF52832 multiprotocol SoC combines the Arm Cortex M4 processor with floating point unit (FPU), with a 2.4GHz multiprotocol radio (supporting Bluetooth 5, ANT™, and proprietary 2.4GHz RF protocol software) featuring -96dB RX sensitivity, with 512kB Flash memory and 64kB RAM. 

“The Nordic nRF52 SoCs offered Forkbeard the best combination of price, software features, battery life, and communication performance across the Proximity Monitor solution’s Bluetooth LE-enabled tags, beacons, and gateway,” says Wilfred Booij, CTO at Forkbeard Technologies. “Nordic’s SoftDevices made it easy for Forkbeard to offer OTA-DFUs [over-ther-air device firmware updates] while maintaining low level control over communication behavior that allows us to offer a long battery life. 

“Forkbeard developed application code for the Proximity Monitor solution relying on the excellent example code made available by the Nordic Software Development Kit [SDK]. In addition, Nordic’s responsive application team and reference designs were important enablers in quickly realizing a number of new products as part of our Covid-19 offering.”