Chen Shyr-Kuen, Kao Tsair, Chan Chia-Tai, Huang Chih-Ning, Chiang Chih-Yen, Lai Chin-Yu, Tung Tse-Hua, Wang Pi-Chung
Department of Computer Science and Engineering, National Chung Hsing University, Taichung, Taiwan.
IEEE Trans Inf Technol Biomed. 2012 Jan;16(1):6-16. doi: 10.1109/TITB.2011.2171704. Epub 2011 Oct 13.
Patient monitoring systems are gaining their importance as the fast-growing global elderly population increases demands for caretaking. These systems use wireless technologies to transmit vital signs for medical evaluation. In a multihop ZigBee network, the existing systems usually use broadcast or multicast schemes to increase the reliability of signals transmission; however, both the schemes lead to significantly higher network traffic and end-to-end transmission delay. In this paper, we present a reliable transmission protocol based on anycast routing for wireless patient monitoring. Our scheme automatically selects the closest data receiver in an anycast group as a destination to reduce the transmission latency as well as the control overhead. The new protocol also shortens the latency of path recovery by initiating route recovery from the intermediate routers of the original path. On the basis of a reliable transmission scheme, we implement a ZigBee device for fall monitoring, which integrates fall detection, indoor positioning, and ECG monitoring. When the triaxial accelerometer of the device detects a fall, the current position of the patient is transmitted to an emergency center through a ZigBee network. In order to clarify the situation of the fallen patient, 4-s ECG signals are also transmitted. Our transmission scheme ensures the successful transmission of these critical messages. The experimental results show that our scheme is fast and reliable. We also demonstrate that our devices can seamlessly integrate with the next generation technology of wireless wide area network, worldwide interoperability for microwave access, to achieve real-time patient monitoring.
随着全球老年人口的快速增长，对护理的需求不断增加，患者监测系统变得越来越重要。这些系统使用无线技术来传输生命体征以进行医学评估。在多跳ZigBee网络中，现有系统通常使用广播或多播方案来提高信号传输的可靠性；然而，这两种方案都会导致网络流量和端到端传输延迟显著增加。在本文中，我们提出了一种基于任播路由的无线患者监测可靠传输协议。我们的方案自动选择任播组中最接近的数据接收器作为目的地，以减少传输延迟以及控制开销。新协议还通过从原始路径的中间路由器启动路由恢复来缩短路径恢复的延迟。基于可靠传输方案，我们实现了一种用于跌倒监测的ZigBee设备，该设备集成了跌倒检测、室内定位和心电图监测。当设备的三轴加速度计检测到跌倒时，患者的当前位置通过ZigBee网络传输到急救中心。为了弄清楚跌倒患者的情况，还会传输4秒的心电图信号。我们的传输方案确保了这些关键消息的成功传输。实验结果表明，我们的方案快速且可靠。我们还证明了我们的设备可以与无线广域网的下一代技术——全球微波接入互操作性无缝集成，以实现对患者的实时监测。
