英文翻译 无线心电监护系统设计

基于蓝牙的心电监护系统的设计和实现
摘要——便携式的远程心电监护系统设计是远程医学和远程护理中的一个的最重要的领域。

本文我们提出一种低成本和基于无线传输的便携式的实时心电采集、存档和可视化于移动电话和个人计算机心电监护系统。

我们设计了采集模块和实现移动设备和个人计算机可视化工具。

一、导言
移动远程医疗系统正变得越来越重要的时候，特别是对于被隔离或者远行在外离医院很远的病人。

这些系统必须是结合低成本，低功耗小型设备，并且应该有一个接口，由病人使用。

结合入诸如蓝牙，GPRS和GSM或Wi – Fi的技术到这些系统中，允许无线传输到控制或健康中心[1-4]。

本文介绍了一种成本低，结合实时采集，处理，储存心电活动到移动电话，PDA或个人电脑的可视化无线传输能力的便携式系统。

在一些项目中已经开发的应用程序，用于监察移动设备，其样品可以从基地获得的心电图标准数据，或他们有扩展的心电图模块。

在另一些项目中提出通过软件来降低噪音或心脏疾病分类为信号处理技术。

在这项工作中，我们描述了无线传输功能（蓝牙和GSM / GPRS），以及为移动设备的实时可视化工具都心电图的采集模块的实现。

其结构如下。

在下面的部分系统的分析，对采用的技术和开发环境进行了描述。

在第三节和第四节的硬件和软件将实施详细解释。

最后的结果与原型一起的结论都显示在第五节。

二、系统描述
该系统由三个模块组成：病人的采集和处理器板（PA P-B T）的，PC控制器（MCU- PC）的医疗控制单元，和移动电话（MCU-MP）的医疗控制单元。

（图一）
该MCU- PC模块是一个用户界面，能模拟心电监护仪和提供了以下功能：与PAP-BT，心电图连接和可视化，数据存储，和GSM/ GPRS通信的蓝牙通信。

该应用程序运行在的任何配有蓝牙和Java虚拟机的移动电话或PDA的移动终端上。

它的用户界面允许与其他设备，进行心脏信号和实时数据信号的可视化通信。

该采集模块由一个生物电放大器，一个带通滤波器，微控制器和蓝牙芯片的无线传输。

a、选定技术
我们选择蓝牙作为传输协议，因为它是最商业化的移动设备中使用。

它是一种短距离的技术，允许安全，可靠的通信，并且有一个普遍接受的标准。

在发展中国家在移动设备，我们使用的J2ME，一个面向Java平台的小型嵌入式图形和有限制的计算资源设备的应用程序。

为PC设计的应用程序是在J2SE，它允许从底层的操作系统抽象开发，并提供了众多串行通信库，蓝牙等。

b、开发环境
规范，设计和采集模块的实施使用的是Or CAD，P - CAD[14]y MPLAB IDE中。

Java应用程序的开发使用的是Eclipse环境。

在Docklight仿真工具是用来测试所有串行通信。

在J2ME的无线工具包允许执行小设备，如移动电话应用试验。

三、硬件描述
我们的PAP-BT电信设备由多个功能模块。

（图2）
a、传感器
在我们的心电监护系统中采用三个电极。

被采集的信号由Einthoven双极导线首次传输（图3）。

通常，电极正极在我的左臂（LA）和电极负极在右侧手臂（RA），测量两臂之间的电位差。

在这个和其他两个肢体导联，右腿上的电极作为记录的数据的参考电极。

b、生物电放大器
典型的心电采集值低的传感器（值为1至3毫伏）要求放大器的增益是1000，在0,05和200赫兹的带宽之间和大于110分贝或更大的的共模抑制比使用。

b、信号调理
该模块包括通滤波器，以消除元件和高频噪音的。

c、心电监护系统中信号的数字
一个PIC16F876微控制器用于模拟到数字的转换。

这个装置是成本低（5€），8位CMOS 闪存单片机在RISC10位的多通道的模拟数字转换器技术为基础。

它的信号的频率可以达到200赫兹，所以我们选择一个500 Hz的采样频率与一个8位微控制器通过的决议规定。

扩展到12位，以满足远程信息处理紧急服务的要求[17]并且通过选择一个12位转换器的微控制器前进。

d、蓝牙无线传输
蓝牙模块使用了BISM II的EZURIO[18]（图4）芯片。

无论是微控制器和蓝牙芯片都参与了这一进程。

数据包包含信号信息发送到芯片，用他们的USART的接口模块。

通过蓝牙连接到PAP-BT模块的任何设备可以因此实时获得它们。

三、软件说明
该软件开发可以分为两个层次：与微控制器相关的低层次的软件，和在PC和移动电话中应用的高层次软件。

a、低层次的软件：微控制器
微控制器已被编程后可以实现下列功能：采集和数字化心电信号，建立并连接到蓝牙手机和发送数据。

蓝牙模块允许提供一种通过AT级的API通信，从而通过完整的蓝牙协议栈彻底释放程序员。

微控制器所采取的步骤可以分为以下几个阶段：
i) 蓝牙配置初始化：设备设置为可见，认证功能被激活，串行通信服务被激活，它被分配一个名称为“试验心电监护系统“中。

此名称将显示在移动电话中，它连接到PAP-BT模块。

ii) 开始提供搜索服务“SPP Test ECG“设备。

这项服务将使我们能够监测病人的心电图。

iii) 一旦连接到移动设备时，发送包含信号的类型和大小的数据包。

发送的数据包中有100心电监护系统中值的大小。

每2毫秒发送五个数据包。

b、医疗控制单元：移动电话
用于嵌入式设备，如手机或掌上电脑，应用程序提供了通过蓝牙端口名为“SPP Test ECG“服务的SPP设备，能够允许我们用于实时监察病人的心电监护系统中。

该申请已开发使用的嵌入式设备，J2ME的Java平台。

蓝牙通讯的编程使用蓝牙API（符合JSR82）。

二进制文件获得使用J2ME无线工具包。

若要从PAP-BT模块这项服务，用户应该选择“BTMovilECG“在手机的应用。

我们的软件服务SPP在URL封装，将显示可用的服务类型蓝牙设备，以及设备的类型提供的服务。

四、医疗控制单元：个人电脑。

这个应用程序监控病人的心电信号，接收他们的数据和可视化，如果用户需要它则存储他们。

它也允许与其他嵌入试移动设备的通信。

此工具的可能应用是在一个接收心电图数据的医院急症室。

用户界面显示，如果图5。

该应用程序是基于J2SE平台开发的。

对于无线的通信我们已经使用Java蓝牙通信协议栈。

通过用户界面，用户可以观察到的实时心电信号。

它的应用程序具有以下功能：
•通讯与通过蓝牙的采集模块
•心电可视化
•心电储存
•心电信号发送到其他设备。

•登录窗口将可视化所有发生的事件。

五，结果
采集，处理和蓝牙传输模块（APA- BR）的设计，并在5 ×4厘米原型（图6）实现。

被采集的信号通过第一个Einthoven双极导线。

其他多个电极的使用已被考虑纳入设计。

蓝牙通信已经进行了成功（图7）。

六、结论
我们已经制定了一个采集和可视化心电图的移动设备系统，成本低，易于为病人安装，对这方面知识陌生的医生也一样。

它的设计可以很容易地更新和技术的进一步发展以提供更多的信息系统。

结合技术，如蓝牙和GSM / GPRS，都为计算机和移动设备的软件工具开发协议实
现了大范围的应用场景。

未来的研究包括连接PC的应用程序到医院数据库，心电的信号，自动检测硬件处理的病症。

鸣谢
这项工作是在IM3的（G03/185）研究网络的西班牙机关Fondo de Investigaciones Sanitarias
框架开发。

Wireless ECG based on Bluetooth protocol: design and
implementation.
Abstract-The design of portable systems for remote monitoring of cardiac activity is one of the most important fields in telemedicine and telecare. In this paper we present
a low cost, portable system with wireless transmission for real time ECG acquisition, archiving and visualization both in a mobile phone and a PC. We have implemented the acquisition module and the visualization tool for the mobile device and the PC.
I. INTRODUCTION
Mobile telemedicine systems are becoming more important all the time, especially in the care of patients that are isolated or travelling, far from a reference hospital. These systems must be embedded in low cost, small devices with low power consumption, and should have an interface that is usable by the patient.
Incorporating technologies such as Bluetooth, GPRS, GSM or Wi-Fi to these systems allows the wireless transmission to health or control centers [1-4].
This paper describes a low cost, portable system with wireless transmission capabilities for the acquisition, processing, storing and visualization in real time of the electrical activity of the heart to a mobile phone, a PDA or a PC.
Several groups [5] have developed applications to monitor the ECG in mobile devices, where the samples have been obtained from standard data bases [6], or they have development the ECG module [7]. Other works [810] have proposed techniques for signal processing via software to reduce noise or classify heart pathologies. In this work we describe both the implementation of the acquisition module with wireless transmission capabilities (Bluetooth and GSM/GPRS), and the tool for real time ECG visualization in mobile devices.
The structure is the following. In the following section system analysis, employed technology and development environment are described. In sections III and IV hardware and implemented software will be explained in detail. Results and final prototype, together with the conclusions are shown in section V.
II. SYSTEM DESCRIPTION
The system consists of three modules: the patient’s acquisition and processing board (PAP-BT), the medical control unit in the PC (MCU-PC), and the medical control unit in the mobile phone (MCU-MP). See figure 1
The MCU-PC module is a tool with a user interface that simulates an ECG monitor and offers the following functionalities: Bluetooth communication with the PAPBT, ECG reception and visualization, and data storage, and GSM/GPRS communication.
The application running on the mobile terminal runs on any mobile phone or PDA equipped with Bluetooth and a Java virtual machine. Its user interface allows communications with other devices, reception of cardiac signals and real-time data signal visualization.
The acquisition module consists of a bioamplifier, a bandpass filter, a microcontroller and a Bluetooth chip for wireless transmission.
A. Selected technology
We have chosen Bluetooth as transmission protocol as it is the one used by most commercial mobile devices. It is a short range technology that allows secure and robust communications, apart from a universally accepted standard, described in [11].
For developing the application in the mobile device we have used J2ME [12], a Java platform oriented to small embedded devices with restricted graphical and computational resources.
The application for the PC was Developer in J2SE, which allows an abstraction from the underlying operating system, and offers a great number of libraries for serial communications, Bluetooth, etc.
B. Development environment
The specification, design and implementation of the acquisition module were carried out using OrCAD. [13], P-CAD. [14] y MPLAB. IDE [15].
Java applications were implemented using the Eclipse environment [16].
The Docklight simulation tool was used to test all serial communications. The J2ME-Wireless Toolkit allowed performing application trials in small devices such as a mobile phone.
III. HARDWARE DESCRIPTION
Our PAP-BT device consists of several functional blocks (Figure 2).
A. Sensors
In our ECG we use three electrodes. The acquired signal represents the first Einthoven bipolar lead (Figure 3). By convention, lead I have the positive electrode on the left arm (LA), and the negative electrode on the right arm (RA), and therefore measure the potential difference between the two arms. In this and the other two limb leads, an electrode on the right leg serves as a reference electrode for recording purposes.
B. Bioamplifier
The low values typical of the ECG acquired by the sensors (values between 1 and 3 mV) require the use of
an amplifier with a gain of 1000, a band with between 0,05 and 200 Hz and a CMRR greater than 110 dB.
B. Signal conditioning
This module consists of a band pass filter to eliminate the continuous component and high frequency noise.
C. ECG signal digitizing.
A PIC16F876 microcontroller is used for analog to digital conversion. This device is lo w cost (5€) 8-bit CMOS Flash Microcontroller based on RISC technology with 10-bit multi-channel Analog to Digital converter. The signal frequency can reach 200 Hz, so we have selected a 500 Hz sampling frequency, with an 8 bit resolution, as provided by the microcontroller. Extension to 12 bits to fulfill the requirements of telemetric emergency services [17] is straight forward by choosing a microcontroller with a 12 bit converter.
D. Bluetooth wireless transmission
The Bluetooth module used was the BISM II chip from EZURIO [18] (Figure 4).
Both the microcontroller and the Bluetooth chip are involved in this process. Packets that contain signal information are sent to the chip, using their USART module as interface. Any device connected via Bluetooth to the PAP-BT board can thus receive them in real-time.
IV. SOFTWARE DESCRIPTION
The software developed can be divided into two levels: low level software associated to the microcontroller, and high level software for the applications in the PC and the mobile phone.
A. Low level software: Microcontroller
The microcontroller has been programmed to perform the following functions: capture and digitize the ECG signal, establish the connection to the Bluetooth phone and send the data.
This Bluetooth module allows provides an API for communication through the AT level, freeing the programmer from implementing the complete Bluetooth stack.
The steps taken by the microcontroller can be divided into the following stages:
i) The Bluetooth configuration is initialized: the device is set as visible, authentication functions are activated, a serial communication service is activated and it is assigned a name ¡°TEST ECG¡±. This name will be shown in the mobile phone when it connects to the PAP-BT module.
ii) Start to search for devices offering the service “SPP Test ECG”This service will allow us to monitor the patient’s ECG.
iii) Once connected to the mobile device, the information about the type of signal and the size of the data packet is sent. Packets sent have a size of 100 ECG values. Five packets are sent every 2 ms.
B. Medical Control Unit: Mobile Phone
The application for embedded devices, such as mobile phones or PDA’s offers a service in the SPP port of the device via Bluetooth, named “SPP Test ECG” that will allow us to monitor the patient’s ECG in real-time.
The application has been Developer using the Java platform for embedded devices, J2ME. The Bluetooth communication was programmed using the Bluetooth API (JSR 82). Binaries were obtained using the J2ME Wireless Toolkit.
To access this service from the PAP-BT board, the user selects the “BTMovilECG” application in the phone. Our software starts the SPP service encapsulated in a url that will show the type of service available to Bluetooth devices, and what type of device is offering the service.
C. Medical Control Unit: PC.
This application monitors the patient’s ECG signal, receives the data and visualizes them, storing them if the user requires it. It also allows communication with other embedded mobile devices. A possible application of this tool is to receive ECG data in the hospital from an emergency unit.
The user interface is shown if figure 5.
The application was Developer on the J2SE platform. For wireles communication we have used the Java Bluetooth communication stack.
Through the user interface, a user can observe the ECG signal in real-time. The application has the following functionalities:
.Communication via Bluetooth with the acquisition board
. ECG visualization
. ECG storage
. Sending the ECG signal to other devices.
. Log window to visualize all the events as they happen.
V. RESULTS
The acquisition, processing and Bluetooth transmission module (APA-BR) was designed and implemented in a 5 x 4 cm prototype (figure 6). The acquired signal represents the first Einthoven bipolar lead [19]. The use of other leads or the incorporation of more electrodes has been contemplated in the design.
Bluetooth communication has been carried out successfully (Figure 7).
VI. CONCLUSIONS
We have developed a low cost system for ECG acquisition and visualization in mobile devices which is easy to install for a patient, as well as for a physician with little previous knowledge. Its design allows for easy technological updates and further development to provide more intelligence to the system. Incorporating technologies such as Bluetooth and GSM/GPRS, and the development of software tools both for a computer and for mobile devices enables a large range of application scenarios. Future research includes connection of the PC application to a hospital database, and hardware processing of the ECG signal for automatic detection of pathologies. ACKNOWLEDGEMENTS
This work was Developer in the framework of the IM3 (G03/185) Research Network of the Spanish Fondo de Investigaciones Sanitarias.。