New wearable communications system offers potential to bridge digital health divide

Wearable devices that use sensors to monitor biological signals can play an important role in healthcare. These devices provide valuable information that allows providers to predict, diagnose and treat various conditions while improving access to care and reducing costs.

However, wearable devices currently require significant infrastructure, such as satellites or antenna arrays using cellular signals, to transmit data, making many of these devices inaccessible to rural and under-resourced communities.

A group of researchers at the University of Arizona set out to change that with a wearable monitoring system capable of sending health data up to 15 miles away – much further than Wi-Fi or Bluetooth systems – without no significant infrastructure. Their device, they hope, will help make access to digital health more equitable.

Researchers present new engineering concepts that make their system possible in the journal Proceedings of the National Academy of Sciences.

Philipp Gutruf, assistant professor of biomedical engineering and the Craig M. Berge Professor in the College of Engineering, led the study in the Gutruf lab. Co-lead authors are Tucker Stuart, a UArizona PhD in biomedical engineering alumnus, and Max Farley, an undergraduate studying biomedical engineering.

Designed for ease, functionality and the future

The COVID-19 pandemic and the strain it has placed on the global health system have focused attention on the need for accurate, rapid and robust remote patient monitoring, Gutruf said. Non-invasive wearable devices currently use the Internet to connect clinicians to patient data for aggregation and investigation.

“These Internet-based communications protocols are efficient and well-developed, but they require cellular coverage or Internet connectivity and primary power sources,” said Gutruf, who is also a member of the UArizona BIO5 Institute. “These requirements often leave individuals in remote or resource-limited environments underserved.”

In contrast, the system developed by Gutruf Lab uses a low-power wide area network, or LPWAN, which provides a distance 2,400 times greater than Wi-Fi and 533 times greater than Bluetooth. The new system uses LoRa, a patented type of LPWAN technology.

“Choosing LoRa addressed previous limitations associated with power and electromagnetic constraints,” Stuart said.

Along with the implementation of this protocol, the laboratory developed circuits and an antenna which, in usual LoRa compatible devices, is a large box that fits perfectly into the soft wearable. These electromagnetic, electronic and mechanical characteristics allow it to send data to the receiver over a long distance.

To make the device almost imperceptible to the wearer, the laboratory also allows its batteries to be recharged over two meters away. Software electronics and the device’s ability to harvest energy are keys to the performance of this one-of-a-kind monitoring system, Gutruf said.

Gutruf Lab calls the wearable soft mesh biosymbiotic, meaning it is custom 3D printed to fit the user and is so discreet that it almost begins to look like a part of their body . The device, worn on the lower forearm, stays in place even during exercise, ensuring high-quality data collection, Gutruf said. The user carries the device at all times and it charges without removal or effort.

“Our device enables continuous operation for weeks with its wireless power transfer feature for interaction-free charging, all done in a small package that even includes built-in calculation of health metrics,” Farley said.

Gutruf, Farley and Stuart plan to further improve and extend communication distances with the implementation of LoRa wireless network gateways that could serve hundreds of square kilometers and hundreds of device users, using only a small number of connection points.

The wearable device and its communications system have the potential to facilitate remote monitoring in underserved rural communities, provide high-fidelity recording in war zones and monitor health in busy cities, Gutruf said , whose long-term goal is to make technology accessible to everyone. the communities that need it most.

“This effort is not just a scientific effort,” he said. “This is a step towards more accessible digital medicine, regardless of geographic and resource constraints.”