A storage-free data parasitizing scheme for wireless body area networks

With the increasing sophistication and maturity of biomedical sensors and the significant advances on low-power circuits and wireless communications technologies, wireless body area networks (WBANs) have emerged recently to provide pervasive health monitoring for humans. In WBANs, smart phones can serve as data sinks to forward the sensing data to back-end servers. Due to the battery concern of smart phones and the postural changes of humans, temporary disconnection between sensors and their associated smart phones may frequently happen in WBANs. In this case, the sensing data would be lost when the limited memory space of sensors overflows. To prevent excessive data loss, this paper proposes a scheme to parasitize the data on existing public Wi-Fi networks, once the links from sensors to the smart phones become unavailable. Specifically, an optimization problem to maximize the time during which data loss can be avoided by exploiting the data parasitizing scheme is formulated, where a decision set of the packets´ size and sending timing to public Wi-Fi networks needs to be determined. We develop an offline algorithm to obtain an optimal decision set and present an efficient online algorithm for practical implementations. The feasibility of the proposed scheme and the efficacy of the algorithms are demonstrated through prototype implementations on a WBAN testbed with biomedical sensor devices for real-world experiments.