Research on Data Privacy Protection Algorithm with Homomorphism Mechanism Based on Redundant Slice Technology in Wireless Sensor Networks

Wireless transmission method in wireless sensor networks has put forward higher requirements for private protection technology. According to the packet loss problem of private protection algorithm based on slice technology, this paper proposes the data private protection algorithm with redundancy mechanism, which ensures privacy by privacy homomorphism mechanism and guarantees redundancy by carrying hidden data. Moreover,it selects the routing tree generated by CTP(Collection Tree Protocol) as routing path for data transmission. By dividing at the source node, it adds the hidden information and also the privacy homomorphism. At the same time,the information feedback tree is established between the destination node and the source node. In addition, the destination node immediately sends the packet loss information and the encryption key via the information feedback tree to the source node. As a result,it improves the reliability and privacy of data transmission and ensures the data redundancy.

The Comparative Research on the Location Technology of Wireless Sensor Networks

Wireless Sensor Network (WSN) which is composed of lots of self-organizational intelligence nodes has become new technology of information acquisition and processing. Location technology is one of the key technologies in WSN. There are many kinds of location algorithms currently and the research to performance evaluation and applicability analysis of algorithms has fundamental significance. For this reason, the paper firstly elaborated the performance evaluation indexes of location algorithms, and analyzed the location prin-ciples, characteristics and current fundamental problems to typical and some new location algorithms, and then analyzed and compared some typical location algorithms according to the location accuracy, node den-sity and hardware requirement, obtaining the sphere of application of these algorithms and pointing out the problems which need to be solved in WSN currently.

Wireless Mesh Technology and Network

Wireless Mesh Network (WMN) has been actively researched and developed as a new network technology to support broadband high- speed multimedia services . This paper discusses WMN technology and applications , and introduces the basic technologies , typical applications and current development of the WMN. With the future development of wireless distribution technology and network, wireless Mesh technology and network will become the key networking technology and architecture of wireless mobile communications , and will be widely used in various wireless networks with more important roles .

Ubiquitous Access Technology for Wireless Digital Home Networks

As an important branch of telecommunication technology, digital home networks have quickly developed in recent years. Although architecture of the digital home network based on telecommunication networks has been standardized in China, only wireless access is defined to be allowable. Therefore, it becomes the focus of further research how to establish a wireless digital home network. This article proposes the concept and shows the architecture of ubiquitous access for wireless digital home networks. Moreover, key technologies for ubiquitous access are discussed here, including cognitive radio, the concept of wireless Mesh, generic link transfer mechanism, Quality of Service (QoS) guarantee mechanism, Electromagnetic Compatibility (EMC) and coexistence of heterogeneous systems.

Cognition Based Reconfigurable Wireless Network Technology

The End-to-End Reconfigurability (E2R) project aims at realizing the convergence of the heterogeneous radio networks and the optimal utilization of the radio resources. With the continuous development of E2R technology and cognitive theory, the evolution from existing radio networks to future reconfigurable radio networks with the cognitive ability becomes possible. Nowadays the research aspects of E2R include the system architecture of reconfigurable radio networks and some key technologies for their evolution.

Key Technologies of Wireless Heterogeneous Network Security

Convergence and collaboration of heterogeneous networks in the next generation public mobile networks will be a subject of universal significance. Convergence of heterogeneous networks, as an effective approach to improve the coverage and capacity of public mobile network, to enable communication services, to provide Internet access and to enable mobile computing from everywhere, has drawn widespread attention for its good prospects in application. Construction of security system for wireless heterogeneous networks and development of new security models, key security techniques and approaches are critical and mandatory in heterogeneous networks development. Key technology of wireless heterogeneous networks security covers security routing protocol, access authentication, intrusion detection system, cooperative communication between nodes, etc.

Wireless Mesh Networks and Cooperative Relaying Technologies

The Wireless Mesh Network (WMN) has become a focus in research of wireless broadband communications . In a switching technologies - based wireless Mesh network, the entire network is regarded as an IP subnet, so it cannot be applied in situations where large coverage is required . The use of cooperative relaying technologies can improve the transmission rate and reliability of wireless link; while the wireless Mesh network, once integrated with cooperative relaying technologies and routing technologies , can improve its spectrum efficiency and cover a wide area . However, there are many problems to be solved with respect to standardization, key technologies research and industrialization. Therefore , the application of cooperative relaying technologies in wireless Mesh networks is still a great challenge .

Scalability Technologies for Wireless Mesh Networks

The continuous increase of data transmission density in wireless mobile communications has posed a challenge to the system performance of Wireless Mesh Networks (WMNs ). There is a rule for wireless Ad hoc networks that the average node capacity decreases while the number of nodes increases , so it is hard to establish a large - scale wireless Mesh network. Network scalability is very important for enhancing the adaptive networking capability of the wireless Mesh network. This article discusses key scalability technologies for Mesh Base Stations (BSs ) and Mesh Mobile Stations (MSs ), such as channel allocation, intelligent routing , multi- antenna , node classification, Quality of Service (QoS) differentiation and cooperative transmission.

Key Technologies of Wireless Mesh Network

The Wireless Mesh Network (WMN) is a special kind of Ad hoc network with a hierarchical network structure . Its backbone transmission network has such characteristics as multi- hop , topology stability, no electricity supply constraints , convergence of flows . Improving the spatial reuse of spectrum is an effective approach to increase network capacity. The linchpin of this approach is to effectively control the interference range between wireless links . The multi- channel networking technology is one of the key technologies of WMN, and its core is the channel allocation through which the channel utilization can be maximized . The mutual interference between multi- hop wireless links should be considered when choosing the routing metrics in WMN. Through the load - balancing routing method , the network capacity and throughput of nodes can be improved .

Investigation of Architecture and Essential Technologies of Wireless Sensor Network

This paper introduces the architecture of wireless sensor networks, presents a cross-layer network management and control mechanism. The key technologies, such as Medium Access Control (MAC) and wireless routing protocols are discussed and compared. A proposal of applying the simple IEEE 802 MAC protocol into the wireless sensor network is introduced. In addition, in order to improve the system capacity, a multi-channel strategy for the sensor nodes is presented for decreasing the blocking probability and suppressing the accessing time delay. It is concluded that there are still a number of problems to be solved, including decreasing power consumption, improving capacity and avoiding access collision, to promote the successful commercial application of wireless sensor network.

Wireless Network Technologies Supporting M2M Applications

When computers and communication devices are available everywhere in the future, the categories of communication will expand to cover not only the man-man and the man-machine, but also the machine-machine (M2M) communication. Someday, the traffic generated by machines will greatly exceed those of man-machine and man-man applications. Large numbers of M2M applications will need various wireless networks to support them. This paper introduces the characteristics, advantages and disadvantages of the currently available various wireless network technologies, including WiFi, Bluetooth, ZigBee, passive RFID and the 802.15 standard networks.

Key Environmental Factors Monitoring System of Low-power Greenhouse Based on WSN Technology

A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs dynamic mon- itoring on the environmental data of temperature, humidity, illumination, soil tempera- ture and humidity of the greenhouse, and it reduces the energy consumption by us- ing solar energy and lithium battery as the power supply mode and dynamic power management algorithm combined with improved routing protocol. Stable and reliable, the system could effectively monitor the key environmental factors in the green- house, making it of certain promotion value.

The ZigBee Based Wireless Sensor and Actor Network in Intelligent Space Oriented to Home Service Robot

In the study of intelligent space oriented to home service robot, an important technology is how to construct an communication network which has the characters of high reliability and easy building. In this paper, based on the characteristics of ZigBee protocol, ZigBee technology is used to construct a wireless sensor and actor network. Several intelligent services based on ZigBee wireless sensor and actor network are shown to certify the reliability of this communication network. ZigBee wireless sensor and actor network builds an information bridge for the components in the intelligent space, the spatially distributed devices are connected together seamlessly. With this network, robot can share the mass information in the intelligent space and improve its performance with 'light-packs', devices in intelligent space, such as lamp, curtain can be controlled autonomously.

Study of Smart Grid Communication Network Architectures and Technologies

Smart Grid (SG) is an emerging paradigm of the modern world to upgrade and enhance the existing conventional electrical power infrastructure from generation to distribution to the consumers in a two-way communication fashion to automate the electrical power demand and supply and make this a cyber-physical system. SG infrastructure key elements, such as smart meters, circuit breakers, transformers, feeders, substations, control centers, grid stations, are required well-formed communication network architectures. SG infrastructure is divided into three main communication networks architectures, such as HAH, NAN, and WAN. Each of these communication network architectures requires reliable, stable, secure, high data rate at real-time with the help of different wireline and wireless communication technologies from HAN to WAN networks. To understand the complete concepts about SG, a concise review is presented and it will help the readers to get foundations of communication network architectures and technologies of SG.

Design and Research on the Chinese Medicine Health Management System Based on the Wireless Sensor Network

In view of the rapid growth of China's aging population and the rising demand for the medical services,it is more necessary to build a health management system of the traditional Chinese medicine based on the wireless sensor networks.This design combines the ZigBee technology,the city grid management and the virtual reality technology,to establish a real-time,accurate and fine health monitoring system,so as to comprehensively improve the efficiency,quality and level of people's health management.

An Internet of Energy Things Based on Wireless LPWAN

Under intense environmental pressure, the global energy sector is promoting the integration of renewable energy into interconnected energy systems. The demand-side management （DSM） of energy systems has drawn considerable industrial and academic attention in attempts to form new flexibilities to respond to variations in renewable energy inputs to the system. However, many DSM concepts are still in the experimental demonstration phase. One of the obstacles to DSM usage is that the current information infrastructure was mainly designed for centralized systems, and does not meet DSM requirements. To overcome this barrier, this paper proposes a novel information infrastructure named the lnternet of Energy Things （IoET） in order to make DSM practicable by basing it on the latest wireless communication technology： the low-power wide-area network （LPWAN）. The primary advantage of LPWAN over general packet radio service （GPRS） and area Internet of Things （loT） is its wide-area coverage, which comes with minimum power consumption and maintenance costs. Against this background, this paper briefly reviews the representative LPWAN tech- nologies of narrow-band Internet of Things （NB-IoT） and Long Range （LORa） technology, and compares them with GPRS and area IoT technology. Next, a wireless-to-cloud architecture is proposed for the IoET, based on the main technical features of LPWAN. Finally, this paper looks forward to the potential of IoET in various DSM application scenarios.

Special Section of Tsinghua Science and Technology on Wireless Computing and Networking

The publication of Tsinghua Science and Technology was started in 1996. Since then, it has been an international academic journal sponsored by Tsinghua University and published bimonthly. This journal aims at presenting the state-of-art scientific achievements in computer science, and other IT fields, and is currently indexed by Ei and other abstracting indices. From year 2013, the journal will be available for open access through IEEE Xplore Digital Library. This year＇s special section on Wireless Computing and Networking of Tsinghua Science and Technology is devoted to gather and present new research that address the challenges in the broad areas of Wireless Networks, Sensor Networks, Wireless Computing and Communication. While Wireless Networks have great potential to provide heterogeneous access and services for ubiquitous users, the demanding communication environment of wireless networks imposes challenges to many interesting research topics, such as channel estimation, communication protocol design, resource management, system design and so on. In Wireless Network research, it is unavoidable to wrestle unique problems such as non-uniform spectrum allocation, various radio resource management policies, economic concerns, the scarcity of radio resources, and user mobility. This Special Section therefore aims to publish high quality, original, unpublished research papers in the broad area of Wireless Computing and Networking, and thus presents a platform for scientists and scholars to share their observations and research results in the field. Specific topics for this special section include but are not limited to：

基于Zigbee技术的无线辐射监测系统的建立

基于Zigbee技术的无线辐射监测系统可对众多辐射监测仪的监测数据进行实时采集和统计分析,无需布线,组网灵活。该辐射监测系统包括多台辐射监测仪及上位机监测平台。辐射监测仪负责测量辐射信息,并将辐射测量结果通过Zigbee模块发送出来。辐射监测平台负责接收辐射测量结果,并将数据在监测平台上进行显示和存储。对辐射监测仪和辐射监测系统进行测试,测试结果表明:辐射监测仪可对在环境本底的基础上增加0.1μSv/h的γ辐射给出可靠报警;辐射监测系统可自动进行无线网络连接,整体运行稳定,数据采集准确,可实现对各个辐射监测仪监测数据的实时采集和存储。

WirelessUSB技术在家庭智能化中的应用

现阶段的家庭智能化产品,功能复杂,价格昂贵,远远超出了普通消费者的实际需求和承受能力。随着通信技术的发展,短距离无线通信技术逐渐被应用到家庭智能化中。家庭监控系统就是WirelessUSB技术在家庭智能化中的应用,它包括三个主要部分:1)家庭监控网络;2)监控中心;3)监控协议与监控软件。家庭监控系统用无线连接的方式实现最基本的家庭设备的监视与控制功能,从而实现一个价格低廉、功能实用、可扩展性强的家庭智能化系统。

5G高铁专网覆盖综合解决方案研究和应用

5G高铁覆盖面临着资源占时短、瞬时容量高、车体损耗大、移动速度快、基站交替快和远近兼顾难等多重挑战。本文针对5G高铁专网的覆盖方案、容量方案、公专网频率协同方案、主设备与天线选型方案、优化创新方案五大关键点开展了对比论证和深入研究,并应用于某高铁规划建设优化实践中,提升了高铁客户的感知,满足了“5G高铁上车”过渡期的高铁场景5G覆盖需求,为后续高铁覆盖项目的应用推广提供了重要的参考。