Bluetooth LE wearable provides continuous Covid-19 temperature monitoring

CWD Innovations

CWD Innovations’ SmartTemp+ employs Nordic’s nRF52832 SoC to wirelessly send body temperature data to smartphone app or gateway

Nordic Semiconductor today announces that CWD Innovations, a Mumbai, India-based technology company, and Nordic’s first official module partner in India, has selected Nordic’s nRF52832 Bluetooth® Low Energy (Bluetooth LE) System-on-Chip (SoC) to provide the short-range wireless connectivity and core processing power for its ‘SmartTemp+’ continuous body temperature monitoring system.  

According to the company, SmartTemp+ is a safe alternative to infrared, digital, and mercury-based thermometers for use in healthcare, government, and home environments. The platform is designed to support the frontline of the healthcare industry during the Covid-19 pandemic by enabling contactless measurement and continuous monitoring of patient temperature. Fever is a symptom in around 88 percent of confirmed Covid-19 cases, according to the World Health Organization (WHO). The SmartTemp+ also enables configurable alerts when body temperature rises above or falls below the patient’s appropriate thresholds and GPS tagging and geofencing for patients under quarantine.
The chip’s processor and memory resources allow it to run complex Bluetooth LE applications
Siddhartha Xavier CWD Innovations

Advanced edge computing

Once attached to the patient’s axial region (including the head, neck, and chest), the 3cm-diameter wearable device uses a built-in temperature sensor to reliably and accurately measure the patient’s body temperature over a period of 15 days with no additional intervention. The nRF52832 SoC’s powerful 32-bit Arm® Cortex® M4 processor is designed to support the Floating Point (FP) and Digital Signal Processing (DSP) computations typical of high-end wireless applications. The microprocessor, combined with the SoC’s generous memory allocation (512kB Flash memory and 64kB RAM), provides ample processing resource to supervise the SmartTemp+’s advanced edge computing algorithms.
Using the Nordic SoC-enabled Bluetooth LE connectivity, the temperature data is automatically transmitted every 60 seconds (or other configured advertising frequency) from the device to a Bluetooth 4.0 (and later) smartphone, from where the user can view the information and self-monitor through the iOS and Android ‘SmartTemp+’ companion app. Alternatively, the data can be transmitted to a proprietary gateway within a hospital using Bluetooth LE, then relayed to a Cloud-based dashboard where the information can be monitored by healthcare professionals or health authorities. This enables early intervention in cases of Covid-19 as well as case mapping across the wider community. 

One month continuous battery life

SmartTemp+ uses a CR2032 coin cell battery to provide up to one month of continuous use before replacement, thanks in part to the ultra-low power characteristics of the Nordic SoC. The nRF52832 has been engineered to minimize power consumption with features such as the 2.4GHz radio’s 5.5mA peak RX/TX currents and a fully-automatic power management system that reduces power consumption by up to 80 percent compared with Nordic’s nRF51 Series SoCs. 
Nordic’s nRF52832 multiprotocol SoC combines the Arm processor, with a 2.4GHz multiprotocol radio (supporting Bluetooth 5.2, ANT™, and proprietary 2.4GHz RF protocol software) featuring -96-dB RX sensitivity. The nRF52832 SoC is supplied with Nordic’s S132 SoftDevice, a Bluetooth 5-certified RF software protocol stack for building advanced Bluetooth LE applications. The S132 SoftDevice features Central, Peripheral, Broadcaster and Observer Bluetooth LE roles, and supports up to twenty connections. 
“We selected Nordic’s nRF52832 SoC for SmartTemp+ because of its ability to support reliable and accurate data processing while providing robust Bluetooth LE wireless connectivity,” says Siddhartha Xavier from CWD Innovations. “The chip’s processor and memory resources allow it to run complex Bluetooth LE applications. 
“CWD Innovations has strong design and product development capabilities across consumer electronics, wearables, industrial automation, and smart lighting sectors, and the Nordic SoC provides both a high level of reliability and robustness for customers using our product development skills across these applications. The availability of Nordic’s technical documentation and reference designs have also proved highly valuable.”