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A set of measurement system for the testing of transmission lines, composing of wireless center station, wireless current acquisition and transmission nodes, wireless voltage acquisition and transmission node, was designed, which was based on wireless communication. The high speed wireless bridge working at 2.4GHz together with the clock synchronization module based on the IEEE1588 communicating protocol were both employed for the communication and time synchronization separately. The measurement system has data storage, waveform display, data analysis, automatic report generation and other functions. The measurement system can greatly reduced arrangement of cables, thereafter improved the test efficiency.

To reduce the number of inter-disturb access points and the interference among access points in same channel, with research on interference issus and channel assignment algorithms of wireless local area network, a scheme suitable for centralized wireless local area network was proposed aiming to minimize the total interference among access points, which comprehensively considerate the number of neighbor and the received power. And then the algorithm with cases was simulated and analyzed, the result of NS2 simulation indicated that the algorithm was simple, effective and feasible, which could realize dynamic adjustment to the wireless LAN RF channel and had a better load balance effect among non-overlapping channels.

This paper analyzed wireless sensor network simulation technology. We discussed the principles of wireless sensor network simulation based on NS2 and constructed a visual simulation model for wireless sensor networks. By adding NS2 protocol and setting the sensor nodes and some simple parameters, the system presented the running process and the performance of the network in the form of animation and graphics. The results show that this method simplifies the process of simulation of wireless sensor networks, and improves the efficiency of wireless sensor networks research and development, which provides support for the development of application-oriented networking of wireless sensor networks.

With the development of information technology, research and application of wireless sensor-actuator network is more and more widely. In this paper, the composition of wireless sensor-actuator network is described, the ZigBee protocol which is a wireless networking protocol is analyzed from multiple aspects in the network. Network architecture, protocol stack hierarchy, building network process, data transfer process, task approach based on ZigBee protocol are studied.

The IEEE802.11 protocol proposed the CSMA/CA mechanism [1] which is more adjustable to the application of the wireless channel based on CSMA. This article will analyze the property of the traffic in the multi-hop wireless network, give the definitions and the migration relationship of four channel states, provide a model for the traffic of the nodes and describe the relationship among the part of the parameters based on the IEEE802.11 protocol.

With the growing popularity of network, more and more people use embedded portable devices to carry out e-commerce by wireless network. However, the security of wireless network is increasingly grim. According to the WPA/WPA2, this paper focuses on authentication issues between access point AP and wireless client STA in the wireless network security, and presents an improved protocol to resolve these problems. The improved one based on 4-way handshake protocol can resist dictionary attack, DOS attack and phishing attack. In the End, the paper analyzes the protocol.

Due to the fact that the wireless spectrum is limited but the wireless demand can grow unlimited, how to improve the wireless capacity becomes one of the hot topics in wireless network field. In this paper, we focus on the scenario of busy wireless environment, and present a protocol with multiple user beamforming. The protocol enables a network to scale its uplink throughput with the number of access points. Theoretical and experimental results show that our protocol have higher uplink throughput compared with 802.11. Moreover, our protocol is the first method that shows that linear scaling of uplink throughput with the number of access points is possible.

The design of S-MAC protocol focuses on how to save energy effectively , how to adapt to the requirements of network scale, node density and topological structure change , and equality, throughput, and bandwidth utilization efficiency are placed on the secondary position This paper points out the classification, basic principal, main mechanisms and key technology of a wireless sensor network MAC protocol.

Unlike other networks based on wireless sensor networks, such as the characteristics of Ad hoc network design algorithm to reduce the energy consumption of wireless sensor networks. The main study of wireless sensor networks in a variety of energy-saving protocols and algorithms, analyze the impact of these agreements on energy saving in different environments, MAC protocol for wireless sensor network design energy efficient use of its improvement, based on the maximum advantage disjoint approximate area set covering algorithm. Energy efficient or superior energy savings in the paper can prolong survival time of the network to provide scientific reference.

This paper mainly analyzed the security of TKIP protocol and VPN technology ,the wireless LAN 802.11 and 802.1x/EXP security vulnerabilities: defects of SSID and MAC Address Filtering, defects of User Authentication Method, security vulnerabilities of WEP Algorithm, defects of 802.1x / EAP and RADIUS Authentication, etc. The author put forward improvement authentication and encryption method as improving wireless LAN security measures.

With the development of wireless network technology, wireless communication is widely used in entertainment, business, factory and other fields. But, for those nuclear power plants which are currently in service, wireless technology did not get fully used, some even in unused condition. Actually, wireless communication system can be used to provide wireless connection between computer and mobile/portable devices, and provide access to LAN system; it also can be used to transmit video and data for cameras and sensors; it can realize wireless expansion of MAIN PABX system, so to meet all kinds of Wireless communication requirements in Nuclear Power Station.

Optimizing the energy consumption of sensor node and prolonging the network lifetime are the key steps to enable the wireless sensor network to enter into practical applications. This paper focuses on studying the energy efficient wireless sensor network routing protocol from the perspective of node energy consumption efficiency and balance, designing the Energy Balanced Adaptive Clustering Hierarchical Protocol (EBACH) and two-layer transceiver model, improving data transmission process to conform to the energy-saving principle of wireless multi-hop data transmission, and analyzing the feasibility and accuracy of the algorithm through simulation.

In order to extend the life span of battery-powered wireless sensor network nodes, this article proceed from the power module, data processing module, wireless module and MAC protocols to design an ultra-low-power wireless sensor network nodes. The nodes improve the power module efficiency maximally, at the same time it utilizes the ultra-low-power data processing module and the asynchronous MAC protocol adopting a sleep wake-up mechanism. Thus it reduces the integrated energy consumption of wireless module significantly. The life span of the nodes has been increased more than three times. In a word, the design in proposed in this paper greatly cuts down the energy consumption of wireless sensor network, which has practical significance of expanding the application space and improving the application effects of wireless sensor network.

This article is about the wireless intelligent home control system design for 2.4GHz wireless communication with the central control board STM32 based on Zigbee technology, and adopting CC2430 module to form wireless sensor networks. The system consists of a main controller and multiple wireless network nodes to enable the users to easily and conveniently control and monitor the home environment and security. With advantages of easy use, simple operation, convenient networking, and good scalability, the system has good application prospects.

Wireless sensor networks with highly dynamic characteristics and limited resources, this paper presents a simple service level management protocol. It realizes service deployment management across different clusters, the request and the response of wireless sensor is simple that based on the protocol data format of XML WSNXML between the clusters. It provides an effective method for the management of shared resources of wireless sensor network and service expansion and realizes service release and deployment management difficulties between various wireless sensor network management based on different management cluster.

In order to resolve the problem of complex wire routing, reliability and lightning-proof difficulty in automatic monitoring system of water conservancy engineering, the paper proposes a volume-compact, easily connected wireless strain collector. The collector modulates the differential strain signal by half-bridge and precise instrumentation amplifier, and employs an up-to-date RF system on chip to realize digitalization for analog voltage signal and wireless transmission. The wireless sensor nodes based on TI's Z-stack protocol possess high performances of network self-organization and network self-healing, and support low power consumption in wireless transmission by sleep mode.

The characteristics and the design factors of wireless sensor network node are talked in this article. According to the design factors of wireless sensor network, this article will mainly point out the design of wireless sensor nodes based a Cortex-M3 Microcontroller STM32F103RE chip. And the wireless communication module is designed with a CC2430 chip. Our wireless sensor node has good performance in our test.

Nowadays, wireless network technology in smart home is rapid gaining popularity duo to its flexible integration into everyday life. The paper introduces a method that adopts 433MHZ communication to establish the wireless network in smart home system based on Si4421 wireless modules. The paper designed the overall idea of how to establish the wireless network, it mainly talk about the wireless module, including both software and hardware. The difficulty lies in the realization of the custom wireless communication protocol. The Si4421 wireless module was tested in data communication and control in smart home system which can work efficiently and reliably, it proved that the wireless module is perfectly suitable for the wireless network construction in smart home with small size package, low consumption, low cost, and strong ability to leap obstacles.

Because of Urumqi Petrochemical Plant needing a large amount of industrial water, in view of their water supply problem, this paper proposed to use wireless data transmission technology to install a wireless gateway on the far flow transmitter, through the equipment RS485 interface, the cumulative flowing data accessed radio station to get the data by using the MODBUS protocol. Eventually it improves the efficiency of the water supply and centralizes management.

In recent years, green computing which refers to maximize energy efficiency during the product's lifetime has attracted more and more concerns. How to use energy effectively in wireless communication systems is also an important issue. In this paper, we propose an energy efficient power control model for wireless communication systems. To control power consumption in wireless communication systems, we design a cross-layer optimization method by a cross layer optimizer which could collect status information from any protocol layer to make optimization decision and send parameter change request to the protocol layers. Experimental results illustrate the effectiveness of the proposed model.

In order to realize the application of the underground wireless monitoring network, in view of the characteristics of the underground wireless monitoring, a kind of multi jump wireless routing protocol based address priority and star-bus topology is designed in this paper. After the analysis of the mine wireless transmission process model and data broadcast problem, considering the technologies of direction control, second localization, the anti-interference, network survival period and so, a method of adding the protocol address and the uplink and downlink flag is proproesd to solve these probles above. Simulation results show that, this protocol can be successfully completed the wireless datatransmission in the underground laneway environment.

Focusing on the wireless relay in heterogeneous wireless networks, a new signal processing architecture of a wireless relay has been proposed. And with an example of the heterogeneous wireless network consisted of GSM and CDMA systems, the detailed design is illustrated. The instance of the wireless relay demonstrates the feasibility of the proposed signal processing architecture.

With the development of the pioneering deployments in multi-hop wireless networks, although the relative research have not proven successful. The performance of routing and transport is often unstable due to contention induced packet losses, especially when the network is large and the offered load is high. A reliable wireless network architecture by using distributed control for large-scale multi-hop wireless networks has been present in this paper, The design objective is to optimize the control performance. This control performance is a complex function of the network parameters, such as throughput, packet delay and packet loss probabilities. The goal of optimizing the control performance imposes implicit tradeoffs on the wireless network design as opposed to the explicit tradeoffs typical in wireless data and voice applications. Our analysis suggests that our approach will deliver improved service to users while greatly reducing support effort and cost.

Since rapid development of wireless network technologies and individuals and enterprises’ urgent demands on application of wireless network, the use of wireless network has been spread rapidly and it is becoming more close to our life. It’s very essential for us to correctly understand and evaluate the characters and performance of wireless network by correctly understanding and studying the errors, using network analog software to simulate the error environment. This paper gives theoretical analyses and discussions to the IEEE 802.11 Protocol wireless networks on the basis of the simulator Tool –NS.

With the development of the technology and society, the resolution of the wireless LAN would be the direction which is leading the smart home LAN’s construction, the IR, RF, Bluetooth, Zigbee, GPRS, and others wireless methods have been applied in the smart home smoothly, like the control, security, data transmission, now it is time to specified the rules for the wireless technology in the smart home, this paper introduces a kind of the smart home wireless bus protocol that based on the Modbus protocol, and the hardware and PC software have been designed for it, the project achieved the operation and communication among the nodes, the test realizes that it has the better data transmission mechanism when adopting the wireless bus protocol, and make sure the reliability of the data transmission between the nodes in the smart home.

The measure to improve the performance of the wireless network channel is of great significance to the building in the wireless network. Due to IPv6 Agreement is the agreement for the next generation network and the core of it, IPHC header compression technology provides IPv6 basic headers and expanding headers with a good support, so we adopt IPHC header compression scheme which groups the data that need to transmitting, introduce retransmission mechanism and header request mechanism to make IPHC have much compression effect on headers. But IPHC header compression scheme is hard on signal channel, it required that loss rate of transportation link is a little lower. In order to let IPHC better adapt to wireless link, compression based on link state is offered: Using simple portioned Markov model to check channel error rate, adopting RTS/CTS access mechanism to search for link state. Apply OPNET simulation software to imitate and finally achieve the desired target. In past two decades, computer network got rapid development, with the application of computers wider and wider. But because of being limited by areas and time, users couldn’t surf on the Internet, communicate with each other, and transport messages at any time and at any place. In this case, the wireless network developed, wireless network technology also produced therewith. Computer wireless network technology included IEEE802.11 collection [1], bluetooth technology, infrared technology, and broadband wireless technology afterwards and so on. Wireless communication technology contained CDMA, GSM, etc [2-5]. According to access ways, wireless access technology was divided into fixed wireless access technology and mobile wireless access technology with many small parts. Wireless access system consisted of wireless base station, wireless base station controller, operation maintenance center and user units. User units which contained single units and multiunits were connected directly with user terminals. Base station, which provided signal-sending and signal-receiving services for users in one district, was controlled by the controller called center station facility to provide an interface with base station side and operation maintenance center, wireless signal channel control and base station monitor, complete the connection of exchanges and routers. Operation control centre is responsible for operating and maintaining wireless access system machines and managing daily network operations.

This paper presents a novel transport layer protocol for multi-level wireless sensor networks. The node of lower level uses a lightweight transmission protocol, which predigests the head of segment and a six-state finite state machine is applied. In order to make the highest nodes convenient for connecting with exterior networks, we modify TCP in the aspects of segment caching and local segment retransmissions, and use the TCP modified in wireless sensor networks directly. Simulation results show that our design can improve the communication capability of the transmission layer in multilevel wireless sensor networks greatly.

With the rapid development of computer network technology, wireless networks have developed to wireless wide area network from a single wireless personal area network. Expansion of coverage was spread from a few meters to a global range and transmission speed was also doubled. The wireless network is gradually used into complicated module network environment, especially in the field of medical treatment, depending on the flexibility and the sound extendibility of its module network. This article is to introduce the wireless LAN technique and its character, and also to express its scientific use in the care.