Authors: Yuan Zhang (University of Jinan, China), Limin Sun (Chinese Academy of Sciences, Beijing, China), Houbing Song (West Virginia University, USA), and Xiaojun Cao (Georgia State University, USA)
Title: “Ubiquitous WSN for Healthcare: Recent Advances and Future Prospects”
Publication: IEEE Internet of Things Journal, vol. 1, no. 4, August 2014
Advances in health monitoring devices promise to usher in a new era in healthcare where health data is being constantly collected (through a wearable monitoring platform) and transmitted to and analyzed by the healthcare provider. In contrast with current medical practices (episodic measurement and care), a ubiquitous health data stream promises to improve diagnosis accuracy, reduce treatment delay, and reduce obstacles for patients to receive treatment.
The authors propose a tiered architecture (access layer, convergence layer, and application layer) for wireless sensor network based healthcare systems. Tier 1 (access layer) comprises the wireless medical sensors that form the wireless sensor network. These sensors share data with remote healthcare providers over Tier 2 (convergence layer) using conventional wireless and wired communication and networking protocols. This data is “synergized” to facilitate analysis of the patient’s health by health care providers at Tier 3 (application layer).
Six potential protocols within the IEEE 802 series standard are analyzed for suitability in health applications. These include:
- IEEE 802.11n (Wireless local area networks, WLAN): not suited to mobility and coverage needs.
- IEEE 802.15.1 (Bluetooth low-energy, BT-LE): although conventional Bluetooth is a poor candidate due to high transmission power, the BT-LE variant is a viable candidate for healthcare monitoring.
- IEEE 802.15.4 (Zigbee): low bandwidth of 250 kbps results in four times the latency of BT-LE and low market penetration make Zigbee inferior to BT-LE.
- IEEE 802.15.6 (Body Area Networks): designed for short range communication and higher security/safety regulations.
- IEEE 802.16e (Wireless Metropolitan Area Networks, MAN, commercialized as WiMAX): designed for high rate transmissions, high mobility, and high security; this protocol is well-suited to healthcare monitoring needs.
- IEEE 802.22 (Cognitive radio): designed to make use of idle spectrum in TV broadcast bands, but its peaceful coexistence with TV is at this point still unclear.
Finally, four principles of a future ubiquitous sensing for healthcare (USH) are identified:
- Proactiveness: transmission of healthcare data to healthcare providers should be done proactively so as to proactively enable necessary interventions.
- Transparency: the design of the system should carefully tradeoff the value of a sensor’s data with the incurred discomfort on the wearer; the healthcare monitoring system should be made as transparent as possible.
- Awareness: “blind” devices that are not context-aware could easily become a nuisance; devices and monitors should be tuned to the context and needs of the wearer.
- Trustworthiness: the transmission of personal health data over a wireless medium requires controls in place to mitigate accidental errors, and secure data from unauthorized access or tampering.