Bluetooth LE/cellular IoT gateway connects vitals monitoring devices to electronic health records 

Nordic Semiconductor today announces that Philadelphia, PA-based healthcare solutions startup, Stel Life, has selected Nordic’s nRF9160 low power System-in-Package (SiP) with integrated LTE-M/NB-IoT modem and GPS in combination with the nRF52840 Bluetooth® Low Energy (Bluetooth LE) advanced multiprotocol System-on-Chip (SoC) to provide the core processing power and wireless connectivity for its ‘Stel Vitals Hub’.   

Designed to integrate with wireless vitals-monitoring devices—such as scales, blood pressure monitors, and wearables—the hub collects and sends vitals data to patients’ preferred Electronic Health Records (EHR) or digital health platform, enabling medical professionals to remotely monitor and provide care for at-home patients. Once plugged-in, the hub uses proprietary ‘passive pairing’ functionality through the proprietary ‘Connected Health OS’ (built on Zephyr RTOS) to wirelessly connect any Bluetooth LE vitals-monitoring devices. This allows care teams to monitor patient health trends and intervene before conditions worsen.  

Cellular IoT connectivity 

Stel Life has specified a custom Fanstel module integrating both Nordic’s nRF52840 SoC and the nRF9160 SiP in the Stel Vitals Hub. The nRF52840 handles Bluetooth LE peripheral management and the nRF9160 is used for cellular connectivity to the Cloud. The Stel Vitals Hub captures the health data from the vitals devices using Nordic SoC-enabled Bluetooth LE connectivity, then instantly transmits the information to the EHR using the cellular IoT connectivity provided by the Nordic SiP – all without the need for a smartphone app or Wi-Fi network. The inclusion of Nordic’s nRF52840 SoC enables the hub to connect a short-range wireless network directly to the cellular network. The solution supports multiple cellular bands and carriers.

The combination of the nRF9160’s 64MHz Arm® Cortex®-M33 dedicated application processor, and the nRF52840 SoC’s 64MHz, 32-bit Arm Cortex M4 processor with floating point unit (FPU), provides Stel Vitals Hub with the processing power to comfortably handle complex and processor-intensive applications.  

The nRF9160 SiP is certified for global cellular IoT applications and comprises a dedicated application processor and memory, multimode LTE-M/NB-IoT modem with integrated RF front end (RFFE), GPS, and power management in a compact 10 by 16 by 1mm package. The processor includes 1MB Flash and 256kB RAM, a range of analog and digital peripherals, automated power and clock management, Arm TrustZone® for trusted execution, and Arm CryptoCell™ 310 for application layer security. The processor communicates with the LTE modem through a BSD secure sockets API and supports the application layer protocol (for example CoAP, MQTT or LWM2M) and the application itself.  

The nRF9160 SiP’s LTE modem supports both SIM and eSIM, offers 700 to 2200MHz LTE band support, 23dBm output power, and single pin 50 Ω antenna- and UICC-interfaces. The LTE stack layers L1-L3, IPv4/IPv6, TCP/UDP, TLS/DTLS are part of the modem firmware. Related products include the nRF9160 DK, a precertified single board development kit and the nRF Connect SDK, a software development kit which includes application layer protocols, application examples, and LTE modem firmware offered as precertified and precompiled downloads. The nRF Connect SDK supports the Zephyr RTOS ecosystem to streamline the development process.  

The nRF52840 SoC’s processor is combined with a 2.4GHz multiprotocol radio (supporting Bluetooth 5.2, ANT™, Thread, Zigbee, IEEE 802.15.4, and proprietary 2.4GHz RF protocol software) and a generous 1MB Flash and 256kB RAM memory allocation. A new radio architecture with on-chip PA provides features -95-dBm RX sensitivity (at 1Mbps Bluetooth LE), a maximum output power of 8dBm, and a total link budget of 103dBm. The SoC is supplied with Nordic’s S140 SoftDevice, a Bluetooth 5-certified software protocol stack for building long range and high data throughput Bluetooth LE applications. The S140 SoftDevice offers concurrent Central, Peripheral, Broadcaster, and Observer Bluetooth LE roles, and supports high throughput and long range modes as well as advertising extensions. 

Multi-band support 

“We selected Nordic’s nRF9160 SiP for the Stel Vitals Hub largely because of the amazing multi-band support provided,” says Sid Kandan, CEO of Stel Life.  

“Nordic’s DevZone open source community and the company’s investment in the Zephyr community were important factors in our decision. We have also been thankful for Nordic's ongoing technical support with any questions or debugging items.”  

• About Stel Life
• About nRF9160
• About nRF52840
• About Nordic Semiconductor