A reliable transmission protocol for ZigBee-based wireless patient monitoring

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.     

Implementation of a WAP-based telemedicine system for patient monitoring

Many parties have already demonstrated telemedicine applications that use cellular phones and the Internet. A current trend in telecommunication is the convergence of wireless communication and computer network technologies, and the emergence of wireless application protocol (WAP) devices is an example. Since WAP will also be a common feature found in future mobile communication devices, it is worthwhile to investigate its use in telemedicine. This paper describes the implementation and experiences with a WAP-based telemedicine system for patient-monitoring that has been developed in our laboratory. It utilizes WAP devices as mobile access terminals for general inquiry and patient-monitoring services. Authorized users can browse the patients' general data, monitored blood pressure (BP), and electrocardiogram (ECG) on WAP devices in store-and-forward mode. The applications, written in wireless markup language (WML), WMLScript, and Perl, resided in a content server. A MySQL relational database system was set up to store the BP readings, ECG data, patient records, clinic and hospital information, and doctors' appointments with patients. A wireless ECG subsystem was built for recording ambulatory ECG in an indoor environment and for storing ECG data into the database. For testing, a WAP phone compliant with WAP 1.1 was used at GSM 1800 MHz by circuit-switched data (CSD) to connect to the content server through a WAP gateway, which was provided by a mobile phone service provider in Hong Kong. Data were successfully retrieved from the database and displayed on the WAP phone. The system shows how WAP can be feasible in remote patient-monitoring and patient data retrieval.     

基于无线传感网络的手机实时医疗监护系统简

针对通过住院观察病人的心电图来对心血管疾病进行诊断的方法的不足,文中采用无线传感网络作为监控系统的信息采集平台,将其应用于人体健康监控领域,设计并实现了一款基于无线传感网络的手机实时医疗监护系统。系统通过无线传感网络来对患者的心电数据进行集中式管理．并可通过医生工作站来实现对患者的远程病情诊断。与目前现有的远程医疗监护系统相比,基于无线佳感网络的手机实时医疗监护系统具有精确度高、实时性好、能耗低、部署方便、设备廉价等一系列优势。     

Compressed sensing for real-time energy-efficient ECG compression on wireless body sensor nodes

Wireless body sensor networks (WBSN) hold the promise to be a key enabling information and communications technology for next-generation patient-centric telecardiology or mobile cardiology solutions. Through enabling continuous remote cardiac monitoring, they have the potential to achieve improved personalization and quality of care, increased ability of prevention and early diagnosis, and enhanced patient autonomy, mobility, and safety. However, state-of-the-art WBSN-enabled ECG monitors still fall short of the required functionality, miniaturization, and energy efficiency. Among others, energy efficiency can be improved through embedded ECG compression, in order to reduce airtime over energy-hungry wireless links. In this paper, we quantify the potential of the emerging compressed sensing (CS) signal acquisition/compression paradigm for low-complexity energy-efficient ECG compression on the state-of-the-art Shimmer WBSN mote. Interestingly, our results show that CS represents a competitive alternative to state-of-the-art digital wavelet transform (DWT)-based ECG compression solutions in the context of WBSN-based ECG monitoring systems. More specifically, while expectedly exhibiting inferior compression performance than its DWT-based counterpart for a given reconstructed signal quality, its substantially lower complexity and CPU execution time enables it to ultimately outperform DWT-based ECG compression in terms of overall energy efficiency. CS-based ECG compression is accordingly shown to achieve a 37.1% extension in node lifetime relative to its DWT-based counterpart for "good" reconstruction quality.     

Time-based compression and classification of heartbeats

Heart function measured by electrocardiograms (ECG) is crucial for patient care. ECG generated waveforms are used to find patterns of irregularities in cardiac cycles in patients. In many cases, irregularities evolve over an extended period of time that requires continuous monitoring. However, this requires wireless ECG recording devices. These devices consist of an enclosed system that includes electrodes, processing circuitry, and a wireless communication block imposing constraints on area, power, bandwidth, and resolution. In order to provide continuous monitoring of cardiac functions for real-time diagnostics, we propose a methodology that combines compression and analysis of heartbeats. The signal encoding scheme is the time-based integrate and fire sampler. The diagnostics can be performed directly on the samples avoiding reconstruction required by the competing finite rate of innovation and compressed sensing. As an added benefit, our scheme provides an efficient hardware implementation and a compressed representation for the ECG recordings, while still preserving discriminative features. We demonstrate the performance of our approach through a heartbeat classification application consisting of normal and irregular heartbeats known as arrhythmia. Our approach that uses simple features extracted from ECG signals is comparable to results in the published literature.     

A mobile care system with alert mechanism.

Hypertension and arrhythmia are chronic diseases, which can be effectively prevented and controlled only if the physiological parameters of the patient are constantly monitored, along with the full support of the health education and professional medical care. In this paper, a role-based intelligent mobile care system with alert mechanism in chronic care environment is proposed and implemented. The roles in our system include patients, physicians, nurses, and healthcare providers. Each of the roles represents a person that uses a mobile device such as a mobile phone to communicate with the server setup in the care center such that he or she can go around without restrictions. For commercial mobile phones with Bluetooth communication capability attached to chronic patients, we have developed physiological signal recognition algorithms that were implemented and built-in in the mobile phone without affecting its original communication functions. It is thus possible to integrate several front-end mobile care devices with Bluetooth communication capability to extract patients' various physiological parameters [such as blood pressure, pulse, saturation of haemoglobin (SpO2), and electrocardiogram (ECG)], to monitor multiple physiological signals without space limit, and to upload important or abnormal physiological information to healthcare center for storage and analysis or transmit the information to physicians and healthcare providers for further processing. Thus, the physiological signal extraction devices only have to deal with signal extraction and wireless transmission. Since they do not have to do signal processing, their form factor can be further reduced to reach the goal of microminiaturization and power saving. An alert management mechanism has been included in back-end healthcare center to initiate various strategies for automatic emergency alerts after receiving emergency messages or after automatically recognizing emergency messages. Within the time intervals in system setting, according to the medical history of a specific patient, our prototype system can inform various healthcare providers in sequence to provide healthcare service with their reply to ensure the accuracy of alert information and the completeness of early warning notification to further improve the healthcare quality. In the end, with the testing results and performance evaluation of our implemented system prototype, we conclude that it is possible to set up a complete intelligent healt care chain with mobile monitoring and healthcare service via the assistance of our system.     

A Novel, Fast, Reliable Data Transmission Algorithm for Wireless Machine Health Monitoring

Vibration-based machine health monitoring is a well-known technique that is commonly used in machine fault diagnosis applications. In conjunction with existing wireless technologies, even machines that are operated in a hazardous or moveable environment can be monitored wirelessly. However, to facilitate a reliable machine health assessment, various sensory data, particularly the vibration signals, must be acquired at a high sampling rate, generating large packets of data. These requirements are impractical in a wireless data transmission context due to the usual low transmission rate, and lengthy transmission time. One possible solution is to compress the captured numerous sensory data before wireless transmission commences. This paper presents a novel data compression algorithm that combines Empirical Mode Decomposition (EMD) with Differential Pulse Code Modulation (DPCM). EMD is effective in decomposing and identifying any instantaneous changes in non-linear, and non-stationary signals that are caused by anomalous operation of machines. After the data have been decomposed and compressed by EMD, the DPCM is applied to further compress the data through the use of linear predictor and quantizer prior to wireless transmission. A pair of Bluetooth based wireless devices was tailor-made to host the EMD and DPCM for performing wireless communication. The effectiveness of the new algorithm has been verified using real machines, operating in a noisy environment. The results prove that the algorithm provides much faster wireless data transmission by significantly reducing the size of sensory data. Nevertheless, it maintains the integrity of sensory data with negligible reconstruction error at the receiving end of the wireless device.      

A secure mobile healthcare system using trust-based multicast scheme

Due to the introduction of telecommunication technologies in telemedicine services, the expeditious development of wireless and mobile networks has stimulated wide applications of mobile electronic healthcare systems. However, security is an essential system requirement since many patients have privacy concerns when it comes to releasing their personal information over the open wireless channels. For this reason, this study discusses the characteristics and security issues with wireless and pervasive data communications for a ubiquitous and mobile healthcare system which consists of a number of mobile devices and sensors attached to a patient. These devices form a mobile ad hoc sensor network and collect data that are sent to a hospital or healthcare center for monitoring. Subsequently, this paper discusses the innovation and design of a novel trust evaluation model. We then propose a secure multicast strategy that employs trust in order to evaluate the behavior of each node, so that only trustworthy nodes are allowed to participate in communications, while the misbehavior of malicious nodes is effectively prevented. We analyze the security properties of our multicast scheme and evaluate its performance based on simulation experiments. Our experimental results demonstrate that our scheme not only achieves the necessary data transmission in mobile environments, but also provides more security with reasonably little additional overhead.     

Design and Implementation of an Algorithm for Cardiac Pathologies Detection on Mobile Phone

The development and the design of telemedicine services have taken a great consideration and care in the domain of wireless communication nowadays. The set of these researches is concerned with old people and lack of infrastructures of reception for those who are at risk or tend to have deterioration in their health condition. Thus, several works of research contributed to develop telemedicine services. They notably focus on the conception and the development of communication architectures between the actors of these systems, monitoring and the development of human??s quality is based on the storage of the collected data at home and analytical tools, and processing of these large quantities of data. Therefore, it is useful to detect and prevent the occurrence of critical situations of a remote person, the transmission of the messages and alarms to concerned actors to be ready to intervene in a case of emergency. Many works and systems undertaken in this field carry out the complete analysis and synthesis of signals on large servers (great capacities, better resolutions??). Moreover, these systems would have required large means and a large infrastructure in their deployment (installation, configuration??), which generates the disadvantage of the excessive expenditure. In this paper, we suggest to introduce and implement this complete treatment for revealing critical situations and pathologies on a simple mobile phone by respecting theirs constraints. The principal objective is to permit a taking off for medical and social dependant people as aged ones, handicapped, in order to the adaptation with their environment domestically and make up their incapacities. In this case, it is indispensable to make a diagnostic in a real time and well manage the patient??s computerized data between the various medical actors with the permanent security insurance of highly risky patients. Furthermore, the need to make a speed diagnostic of patients and to detect their health state, their parameters (medical information) of analyses with efficacy, allows us to gain time while monitoring the cardiac patient. It concerns the implementation of services on mobile terminals for transferring medical information and results of ECG analysis (calculated parameters) in a real time with ensuring the mobility, the permanent security and the reliability insurance in covered zone by the mobile network, PLMN (GSM/GPRS??). Our attention has been focused on the choice of a relevant work. It concerns an application on a mobile terminal (MIDlet) for detecting some cardiac pathologies and monitoring patient in a non-hospital setting. This paper recalls a complete architecture of an economic wireless transmission system with the implementation of an effective algorithm, adapted to the mobile terminal, allowing to the doctor to have the results of the ECG analysis. Thus, the stakes of setting up such systems are numerous, so much for patients, medical staff and the society in general.     

Design and Implementation of a Reconfigurable Mobile Game Controller on Smartphone

Expansion of games industry came in modern life, accompanied with innovative features in a game controller. Nowadays mobile industry is booming with the expansion of the variety of novel technologies, such as the use of 3D accelerometer sensors, high resolution cameras, the capability of connecting to wireless networks and so on. Therefore, a smartphone can be added with the game control functions to become a mobile game controller. In this paper, we propose the design and implementation of making a mobile phone as a game controller using User Datagram Protocol socket programming. This system is developed by Java 2 Standard Edition and Google Android Software Development Kits which has already provided sensor and multi-touch APIs. We successfully realize a reconfigurable mobile game controller on a mobile smartphone to interact with the existing digital games by mapping control functions on the server. Acceptable performance is shown to validate the effectiveness of our solution.     

基于Zigbee的智能医疗系统设计

智能医疗是利用最先进的物联网技术,实现患者与医务人员、医疗机构、医疗设备之间的互动,逐步达到信息化。本文设计了一种智能医疗系统,该系统以STM32为的控制核心,对远程病人的心电,血氧进行采集,并将采集到的数据通过Zigbee无线模块发送到移动Android终端及PC端进行动态的显示,医生根据显示图表及数据进行科学的诊断。     

基于3G的手机远程监控系统

由于传输速度等问题的影响,传统的无线通信技术在远程监控上的应用受到限制。现将第三代移动通信技术（3G）应用到了远程监控系统中,介绍了手机作为信息采集端设备与客户端设备的应用,满足了随时、随地远程监测实时控制的应用需求,并叙述了将采集的信息进行转码处理的过程。还列举了在3G系统中将手机作为终端的具体实例应用,这个系统在当前应用越来越广泛,最后对此系统的其它应用做了简单展望。     

Lightweight Secure Roaming Mechanism Between GPRS/UMTS and Wireless LANs

The third generation partner project (3GPP) has standardized general packet radio service (GPRS) and the universal mobile telecommunications system (UMTS) to provide cell phone communications and wireless Internet services. Although the data transmission rate is lower than that of wireless local area networks (WLANs), GPRS/UMTS covers larger areas. Hence, to achieve higher speed ubiquitous access, we propose a lightweight secure roaming mechanism (LSRM) that integrates GPRS/UMTS and WLAN. Taking advantage of these two technologies, LSRM offers anonymous roaming and friendly subscriber management. Besides, we give a formal security analysis to LSRM based on BAN authentication logic.     

基于GPRS网络的远程心电监护系统

针对通常的心电监护只能在医院实施的问题,研究并开发了一种远程心电实时监护系统。该监护系统将GPRS（通用分组无线电业务）无线发送模块集成到$3C2410高性能微处理器控制的心电信号采集处理模块上,病人佩戴后获取心电数据,借助GPRS移动通信网络实时上传到医院监护中心,经医生诊断后及时将诊断结果反馈给病人,从而实现院外流动病人的远程监护和治疗。该监护仪能在GPRS网络覆盖范围内,随时随地对病人进行心电监护。与现有的同类设备相比,其体积小、重量轻、成本低廉、佩戴方便,监护效果理想。     

A network-assisted flow mobility architecture for optimized mobile medical multimedia transmission

A large part of mobile Health (mHealth) use-cases such as remote patient monitoring/diagnosis, teleconsultation, and guided surgical intervention requires advanced and reliable mobile communication solutions to provide efficient multimedia transmission with strict medical level Quality of Service (QoS) and Quality of Experience (QoE) provision. The increasing deployment of overlapping wireless access networks enables the possibility to offer the required network resources for ubiquitous and pervasive mHealth services. To address the challenges and support the above use-cases in today’s heterogeneous network (HetNet) environments, we propose a network-assisted flow-based mobility management architecture for optimized real-time mobile medical multimedia communication. The proposed system is empirically evaluated in a Pan-European HetNet testbed with multi-access Android-based mobile devices. We observed that the proposed scheme significantly improves the objective QoE of simultaneous real-time high-resolution electrocardiography and high-definition ultrasound transmissions while also enhances traffic load balancing capabilities of wireless architectures.     

A POI-Aware Power Saving Scheme for Ubiquitous Touring Service using Mobile Devices over the Cellular and Wi-Fi Hybrid Network

Location-based service (LBS) is an popular add-on mobile application based on the geographical positions of users. For example, a pedestrian utilizes its smart phone to navigate himself during the trip. Regarding the positioning accuracy and neighboring features of environments, this paper considers the peculiarities of a pedestrian touring service and concentrates on how to save battery power of mobile devices smartly. For power efficiency of positioning, we propose to dynamically adjust the GPS sampling rate with the help of embedded sensors based on the relationship among the current geo-location, motion behavior and physical environment. Furthermore, this paper considers communication restrictions of heterogeneous wireless technologies, including (1) cellular network and (2) Wi-Fi network. Since the cellular network has wider wireless coverage, the proposed scheme downloads neighboring POIs using cellular network. Once the neighboring Wi-Fi hotspots can provide good enough bandwidth, our scheme uses Wi-Fi network instead of cellular network. In order to measure the power consumption, several touring routes are established based on the real-world scenic spots. According to our performance results, the proposed scheme can have less power consumption than other methods.     

Wireless Mesh Networks for In-Home IPTV Distribution

IPTV is considered to be the next killer application. A key, challenging issue is in-home IPTV distribution with affordable deployment cost and sufficient flexibility, scalability, and reliability. In this article, we first survey and compare the emerging wired and wireless communication technologies for broadband home networks, including transmission over power lines, phone lines, coaxial cables or Ethernet cables, and IEEE 802.1 In, ultra wideband and millimeter wave wireless technologies. Considering these promising candidates for future broadband home networks, we propose three wireless mesh network architectures. These enable consumers to enjoy anywhere, anytime IPTV services without rewiring their homes. We compare the cost, reliability, and scalability of the three architectures. We further study their admission regions for IPTV, that is, the number of IPTV connections that can be supported simultaneously with satisfactory QoS. Analytical and simulation results with H.264 HDTV sources over wired, single hop wireless, and multi-hop wireless paths are given. These results can provide important guidelines for future broadband home network design supporting IPTV services.     

Optimal zonal wavelet-based ECG data compression for a mobiletelecardiology system

A new integrated design approach for an optimal zonal wavelet-based ECG data compression (OZWC) method for a mobile telecardiology model is presented. The hybrid implementation issues of this wavelet method with a GSM-based mobile telecardiology system are also introduced. The performance of the mobile system with compressed ECG data segments selected from the MIT-BIH arrhythmia database is evaluated in terms of bit error rate (BER), percent rms difference (PRD), and visual clinical inspection. The compression performance analysis of the OZWC is compared with another wavelet-based (Discrete Symmetric Wavelet Compression) approach. The optimal wavelet algorithm achieved a maximum compression ratio of 18:1 with low PRD ratios. The mobile telemedical simulation results show the successful compressed ECG transmission at speeds of 100 (km/h) with BER rates of less than 10^-15, providing a 73% reduction in total mobile transmission time with clinically acceptable reconstruction of the received signals. This approach will provide a framework for the design and functionality issues of GSM-based wireless telemedicine systems with wavelet compression techniques and their future integration for the next generation of mobile telecardiology systems     

远程无线心电监护系统的软件设计

心血管疾病具有突发性和高危险性,为了及时发现病情,需要对患者进行有效监护。文中设计了一套远程心电监护系统软件,通过对MC9S12XS128单片机底层程序的设计,完成了对心电信号数据的采集和GPRS模块的AT指令控制,由此实现心电信号数据的无线传输。操作简单、界面友好的监护系统部分采用了LabVIEW图形化编程环境,对采集到的心电信号进行分析、处理、显示以及存储,操作者可以实时监测被测者的心电情况,便于及时做出诊断,及早治疗,同时设置了自动报警系统。     

Increasing lifetime of wireless sensor networks using controllable mobile cluster heads

In a static wireless sensor network (WSN), sensors close to the base station (BS) run out of energy at a much faster rate than sensors in other parts of the network. This is because the sensor close to the BS always relays the data for other sensors, resulting in an unequal distribution of network residual energy. In this paper, we propose a scheme for enhancing the network lifetime using multiple mobile cluster heads (CHs) that can move in the WSN in a controllable manner. The CH controllably moves toward the energy‐rich sensors or the event area, offering the benefits of maintaining the remaining energy more evenly, or eliminating multihop transmission. Therefore, the proposed scheme increases the network lifetime. We theoretically analyze the energy consumption in our scheme and propose three heuristical mobility strategies. We further study the collaboration among CHs in order to maintain their connectivity to the BS to ensure the delay requirement for real‐time applications. Simulation shows that network lifetime is increased by upto 75% over existing approach by making CHs always move toward a stable equilibrium point. Our connectivity algorithm provides a best case improvement of 40% in transmission delays over existing schemes. Copyright © 2009 John Wiley & Sons, Ltd.