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1.
3G wireless communications for mobile robotic tele-ultrasonography systems   总被引:1,自引:0,他引:1  
Mobile healthcare (m-health) is a new paradigm that brings together the evolution of emerging wireless communications and network technologies with the concept of 'connected healthcare' anytime and anywhere. In this article, we present the performance analysis of an end-to-end mobile tele-echography using an ultra-light robot (OTELO), over the third-generation (3G) mobile communications network. The experimental setup of the OTELO system over a 3G connectivity link used to measure the system performance is described. The performance of the relevant medical data and the relevant quality of service (QoS) issues defined in terms of the average throughput, delta-time packet delay, and jitter delay are investigated. The real-time 3G performance results show the successful operation of this bandwidth demanding robotic m-health system.  相似文献   

2.
The design of an efficient mobile healthcare system using 3.5G and 4G wireless networks is a challenging problem especially for bandwidth demanding telemedical applications. In this paper, we focus on the concept of medical Quality of Service (m-QoS) applied to a typical bandwidth demanding m-health application. Based on this concept, we propose a novel multiobjective rate-control mechanism for the optimized delivery of diagnostically acceptable ultrasound video images over 3.5G wireless networks. The performance of the proposed algorithm has been evaluated via both simulations and experimental studies. The proposed optimal rate control algorithm achieved performance improvements that are compatible with the medical QoS requirements.  相似文献   

3.
Wireless telemedicine is a new and evolving area in telemedical and telecare systems. Healthcare personnel require realtime access to accurate patient data, including clinical histories, treatments, medication, tests, laboratory results and insurance information. With large-scale wireless networks and mobile computing solutions, such as cellular 3G, Wi-Fi mesh and WiMAX, healthcare personnal can tap into vital information anywhere and at any time within the healthcare networks. The recent introduction of pervasive computing, consisting of radio frequency identification (RFID), Bluetooth, ZigBee, and wireless sensor networks, further extends the potential for exploitation of wireless telecommunications and its integration into new mobile healthcare delivery systems. In this paper, snapshots of current uses and future trends of various wireless communications in the healthcare domain are highlighted. Special attention is given to the challenges of a telemedicine environment equipped with different wireless technologies and how the resulting issues might be addressed in medical services integration to provide flexible, convenient and economical medical monitoring, consultation and healthcare.  相似文献   

4.
Wireless communications are expected to be the dominant mode of access technology in the next century. Besides voice, a new range of services such as multimedia, high-speed data, etc. are being offered for delivery over wireless networks. Mobility will be seamless, realizing the concept of persons being in contact anywhere, at any time. Two developments are likely to have a substantial impact on the mobile communications systems deployed in the twenty-first century: the adoption of International Mobile Telecommunications-2000 and wireless asynchronous transfer mode (ATM). They are two different but cooperative approaches to providing high-speed wireless access. The limitations of the radio-frequency spectrum and radio channel propagation impose special constraints on the technologies of systems to be deployed. To make future mobile systems globally acceptable, standardization efforts are underway in the International Telecommunications Union and the ATM Forum. This paper reviews the international standardization efforts, the challenges to the technologies imposed by the radio spectrum limitations, radio channel propagation-induced distortions, and possible solutions. Evolution, migration, and architecture issues also are discussed  相似文献   

5.
Sun  Y. 《Signal Processing, IET》2009,3(6):431-432
Wireless and mobile communications have developed rapidly in recent years due to the endless demand for broadband multimedia Internet access and wireless connection anywhere and any time. Several 4G standards have been proposed such as WiMax, LTE and IEEE 802.11n. Signal processing plays a key role in the evolution of wireless and mobile communications. With the emergence of various 4G enabling technologies, advanced signal processing has become ever increasingly important for low complexity, low power and efficient physical implementations of future multimedia communication systems. Multi-antenna, multi-frequency, multi-user and cooperative technologies have emerged as powerful enablers for high date rate and highly reliable broadband communications. To harvest the benefits of these technologies maximally, both excellent opportunities and significant challenges are present in the research of signal processing. The aim of this special issue was to publish some most recent advances in the signal processing aspects of these wireless and mobile communication technologies. Five papers have been selected for the special issue. These papers cover various multi-antenna topics including MIMO detection, spacetime equalization, MIMO channel prediction and estimation, and space-time coding. Some papers also consider cooperative relay communications, OFDM, and multiuser systems.  相似文献   

6.
Wireless telemedicine systems: an overview   总被引:8,自引:0,他引:8  
Rapid advances in information technology and telecommunications and, more specifically, wireless and mobile communications - and their convergence ("telematics") are leading to the emergence of a new type of information infrastructure that has the potential of supporting an array of advanced services for healthcare. The objective of this paper is to provide a snapshot of the applications of wireless telemedicine systems. A review of the spectrum of these applications and the potential benefits of these efforts is presented, followed by successful case studies in electronic patient record, emergency telemedicine, teleradiology, and home monitoring. It is anticipated that the progress carried out in these efforts and the potential benefits of emerging mobile technologies will trigger the development of more applications, thus enabling the offering of a better service to the citizen  相似文献   

7.
With the advances in wireless communications and low-power electronics, accurate position location may now be accomplished by a number of techniques which involve commercial wireless services. Emerging position location systems, when used in conjunction with mobile communications services, will lead to enhanced public safety and revolutionary products and services. The fundamental technical challenges and business motivations behind wireless position location systems are described, and promising techniques for solving the practical position location problem are treated  相似文献   

8.
Bandwidth-efficient wireless multimedia communications   总被引:1,自引:0,他引:1  
Commencing with a brief history of mobile communications and the portrayal of the basic concept of wireless multimedia communications, the implications of Shannon's theorems regarding joint source and channel coding for wireless communications are addressed. Following a brief introduction to speech, video, and graphical source coding as well as the cellular concept, a rudimentary overview of flexible, reconfigurable, mobile radio schemes is provided. We then summarize the fundamental concepts of modulation, introduce an adaptive modem scheme, and argue that third-generation transceivers might become adaptively reconfigurable under network control in order to meet backward compatibility requirements with existing systems and to achieve best compromise among a range of conflicting system requirements, complexity and power consumption, robustness against channel errors, etc  相似文献   

9.
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.  相似文献   

10.
This article provides an overview of the activities currently carried out under the IST research program of the European Commission, in the area of mobile and wireless communications and satellite systems. The research orientations specific to wireless communications are described in detail, with reference to the projects active in each area, defining a possible roadmap for the evolution of mobile communications systems beyond UMTS.  相似文献   

11.
下一代无线通信(NextG:Next-generationwireless)的主流是随时随地的无线通信系统和无缝的高质量无线业务。概述了随时随地的无线通信和业务发展情况,并且介绍了为下一代无线通信的发展提供基础的关键技术。  相似文献   

12.
Group communications in wireless networks has been facilitating many emerging applications that require packet delivery from one or more sender(s) to multiple receivers. Due to insecure wireless channels, group communications are susceptible to various kinds of attacks. Although a number of proposals have been reported to secure group communications, provisioning security in group communications in wireless networks remains a critical and challenging issue. This article presents a survey of recent advances in security requirements and services in group communications in three types of wireless networks, and discusses challenges in designing secure group communications in these networks: wireless infrastructure networks, mobile ad hoc networks, and wireless sensor networks.  相似文献   

13.
Broadband wireless communications have gained increased interest during the last few years. This has been fuelled by a large demand on high-frequency utilization as well as a large number of users requiring simultaneous high-data-rate access for the applications of wireless mobile Internet and e-commerce. The convergence of wireless mobile and access will be the next storm in wireless communications, which will use a new network architecture to deliver broadband services in a more generic configuration to wireless customers, and support value-added services and emerging interactive multimedia communications. Large bandwidth, guaranteed quality of service, and ease of deployment coupled with the great advancements in semiconductor technologies make this converged wireless system a very attractive solution for broadband service delivery.  相似文献   

14.
The use of wireless technologies for medical device communication, health monitoring (at hospitals or homes) and mobile healthcare information delivery (i.e. m-Health) is one of the most rapidly growing areas in health-IT research today. The papers which appear in this special issue have been carefully selected from the best IEEE PIMRC 2011 conference. They are highlighting various challenging issues in using wireless technology for healthcare applications such as PHY & MAC innovations for wearable and implantable medical sensors, optical communication and location systems in hospital environments and interference mitigation issues.  相似文献   

15.
The rapid growth of multimedia wireless communications services forces the development of advanced digital wireless systems with high reliability and high speed as well as flexibility for varying traffic conditions. To achieve such advanced wireless systems. New system design concepts different from the conventional ones aiming at increasing system capacity for voice transmission would be required. Since multimedia wireless communications require high quality, high speed, and high flexibility as well as temporary and spatial control of traffic under severe fading environments, the so-called conventional system design concept will be insufficient. New system design concepts and techniques for achieving highly reliable and high-capacity multimedia wireless communications are discussed using both time division multiple access (TDMA) and code division multiple access (CDMA) systems. The demands for high-speed and high-reliability mobile, personal, and multimedia wireless communications services strongly require matching with the trunk network constructed by a broadband optical fiber system or wired system  相似文献   

16.
吴越  林福华 《数字通信》1999,26(4):31-33
无线电通信是下一个世纪的主要接入技术,无线网络了除了提供语音服务之外,还提供多媒体和高速数据业务。本文介绍了第3代国际移动通信系统IMT-2000和无线异步转移模式(WATM)的概念,对它们的关键技术进行了总结,并对其发展方向作了进一步的展望。  相似文献   

17.
A lightweight reconfigurable security mechanism for 3G/4G mobile devices   总被引:1,自引:0,他引:1  
Wireless communications are advancing rapidly. We are currently on the verge of a new revolutionary advancement in wireless data communications: the third generation of mobile telecommunications. 3G promises to converge mobile technology with Internet connectivity. Wireless data, multimedia applications, and integrated services will be among the major driving forces behind 3G. While wireless communications provide great flexibility and mobility, they often come at the expense of security. This is because wireless communications rely on open and public transmission media that raise further security vulnerabilities in addition to the security threats found in regular wired networks. Existing security schemes in 2G and 3G systems are inadequate, since there is a greater demand to provide a more flexible, reconfigurable, and scalable security mechanism that can evolve as fast as mobile hosts are evolving into full-fledged IP-enabled devices. We propose a lightweight, component-based, reconfigurable security mechanism to enhance the security abilities of mobile devices.  相似文献   

18.
The 17 papers in this second part of this special section focus on multifunctional circuits and systems for future generations of wireless communications.  相似文献   

19.
Vast importance is being placed in Europe on the development of third-generation mobile telecommunications systems, since it is expected that mobile and personal communications will become a key driver for growth and innovation in the next millenium as well as being a necessary building block of the wireless information society. Significant progress has been made since 1988 by a number of European Union funded R&D projects working toward the development of future generations of mobile communication concepts, systems, and networks. The ACTS (Advanced Communications Technologies and Services) program will offer, in the period 1995-1998, service providers, communications operators, and equipment manufacturers greater opportunities to master and trial mobile and personal communications services and technologies. From the user's perspective the ACTS program will strive to ensure that current mobile services are extended to include multimedia and broadband services, that access to services are made without regard to the underlying networks, and that convenient, lightweight, compact, and power-efficient terminals adapt automatically to whatever air-interface parameters are appropriate to the user's location and desired services  相似文献   

20.
Mobile wireless communications, which includecellular telephones, land mobile radio, and personalcommunications systems, have experienced enormous growthover the last decade. Data services represent a critical component of future wirelesscommunications, but have received little attention sofar. While some attention has been given to specializedmobile data networks, less has been directed at the ongoing design of data services in evolvingthird generation digital cellular wireless networks. Inthis work we present the results of a simulation studythat explores the performance of a Reservation Random Access (RRA) scheme for transmittingdata packets over a common radio broadcast channel in acellular radio environment. In addition to voicetraffic, we consider data packet traffic generated by interactive applications. It is expected thatsuch applications will be very important in thirdgeneration wireless access mobile communication systems.Through an extensive simulation study of the data message delay distribution, we show that theproposed RRA scheme, originally designed under thePoisson data message arrival process assumption, canalso efficiently operate and be optimized under theextremely bursty data message arrival processcharacterized by independent, identically distributed,Pareto message interarrival times.  相似文献   

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