Farshchi Shahin, Pesterev Aleksey, Nuyujukian Paul H, Mody Istvan, Judy Jack W
Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, CA 90025, USA.
IEEE Trans Inf Technol Biomed. 2007 Nov;11(6):611-8. doi: 10.1109/titb.2007.897600.
Wireless-enabled processor modules intended for communicating low-frequency phenomena (i.e., temperature, humidity, and ambient light) have been enabled to acquire and transmit multiple biological signals in real time, which has been achieved by using computationally efficient data acquisition, filtering, and compression algorithms, and interfacing the modules with biological interface hardware. The sensor modules can acquire and transmit raw biological signals at a rate of 32 kb/s, which is near the hardware limit of the modules. Furthermore, onboard signal processing enables one channel, sampled at a rate of 4000 samples/s at 12-bit resolution, to be compressed via adaptive differential-pulse-code modulation (ADPCM) and transmitted in real time. In addition, the sensors can be configured to filter and transmit individual time-referenced "spike" waveforms, or to transmit the spike height and width for alleviating network traffic and increasing battery life. The system is capable of acquiring eight channels of analog signals as well as data via an asynchronous serial connection. A back-end server archives the biological data received via networked gateway sensors, and hosts them to a client application that enables users to browse recorded data. The system also acquires, filters, and transmits oxygen saturation and pulse rate via a commercial-off-the-shelf interface board. The system architecture can be configured for performing real-time nonobtrusive biological monitoring of humans or rodents. This paper demonstrates that low-power, computational, and bandwidth-constrained wireless-enabled platforms can indeed be leveraged for wireless biosignal monitoring.
用于传输低频现象（即温度、湿度和环境光）的无线处理器模块已能够实时采集和传输多种生物信号，这是通过使用计算效率高的数据采集、滤波和压缩算法，并将这些模块与生物接口硬件相连来实现的。这些传感器模块能够以32 kb/s的速率采集和传输原始生物信号，这已接近模块的硬件极限。此外，板载信号处理功能使得以12位分辨率、4000样本/秒的速率采样的一个通道能够通过自适应差分脉冲编码调制（ADPCM）进行压缩并实时传输。此外，传感器可以配置为过滤并传输单个时间参考的“尖峰”波形，或者传输尖峰高度和宽度，以减轻网络流量并延长电池寿命。该系统能够通过异步串行连接采集八个模拟信号通道以及数据。后端服务器会存档通过联网网关传感器接收到的生物数据，并将其提供给一个客户端应用程序，用户可以通过该应用程序浏览记录的数据。该系统还通过一个现成的接口板采集、过滤并传输血氧饱和度和脉搏率。该系统架构可以配置用于对人类或啮齿动物进行实时无创生物监测。本文表明，低功耗、受计算能力和带宽限制的无线平台确实可用于无线生物信号监测。
