Affiliations: [a] Department of Medical Informatics, School of Allied Health Sciences, Kitasato University, Sagamihara, Kanagawa, Japan | [b] Department of Physiology, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan | [c] Department of Medical Informatics, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
Abstract: BACKGROUND: Hospital real-time location systems (RTLS) are
increasing efficiency and reducing operational costs, but room access tags
are necessary. OBJECTVE: We developed three iPhone 5 applications for an RTLS and
communications using Bluetooth low energy (BLE). METHODS: The applications were: Peripheral device tags, Central
beacons, and a Monitor. A Peripheral communicated with a Central using BLE.
The Central communicated with a Monitor using sockets on TCP/IP
(Transmission Control Protocol/Internet Protocol) via a WLAN (wireless local
area network). To determine a BLE threshold level for the received signal
strength indicator (RSSI), relationships between signal strength and
distance were measured in our laboratory and on the terrace. RESULTS: The BLE RSSI threshold was set at -70 dB, about 10 m.
While an individual with a Peripheral moved around in a concrete building,
the Peripheral was captured in a few 10-sec units at about 10 m from a
Central. The Central and Monitor showed and saved the approach events,
location, and Peripheral's nickname sequentially in real time. Remote
Centrals also interactively communicate with Peripherals by intermediating
through Monitors that found the nickname in the event database. CONCLUSIONS: Trial applications using BLE on iPhones worked well
for patient tracking, and messaging in indoor environments.
Keywords: Real-time location system, Bluetooth low energy, iPhone application
