A Zigbee Technology for Lighting Control Application

Zigbee is wireless communication technology and IEEE 802.15.4 standards for data communication. There are zigbee standards provides network security and application sup port services operating on top of the IEEE 802.15.4 medium access control and physical layer wireless standards and it employs a group of technologies to enable scalable, self - organizations,self - healing networks that can mange various data traffic pattern s. The Zigbee is low - cost, low - power consumption, wireless mesh networking standards and It is designed around low power consumption allowing batteries to essentially last forever. Zigbee is use for monitoring and control applications. This paper presents a zigbee device types, its traffic varities, stucture and use in home automation and the lighting control application

High resilience wireless mesh networking characteristics and safety applications within underground mines

The work presented in this thesis has investigated the feasibility, characteristics and potential applications of low power wireless networking technology, particularly aimed at improving underground mine safety. Following an initial review, wireless technology was identified as having many desirable attributes as a modern underground data transmission medium. Wireless systems are mobile, flexible, and easily scalable. Installation time can be reduced and there is scope for rapid deployment of wireless sensor networks following an emergency incident such as a mine explosion or roof rock fall. Low power mesh technology, relating to the Zigbee and IEEE 802.15.4 LR-WPAN (low-rate wireless personal area network) standards, has been of particular interest within this research project. The new breed of LR-WPAN technology is specifically designed for low power, low data rate wireless sensor applications. The mesh networking characteristics of the technology significantly increase network robustness and resilience. The self-healing, self-organising, multiple pathway redundancy, and highly scalable attributes of mesh networks are particularly advantageous for underground, or confined space, high-integrity safety and emergency applications. The study and potential use of this type of technology in an underground mine is a novel aspect of this thesis. The initial feasibility and review examined the current and future trends of modern underground data transmission systems, with particular focus on mine safety. The findings following the review determined the ideal requirements of an underground data transmission in terms of robustness, integrity, interoperability, survivability and flexibility; with wireless mesh networking meeting many of these requirements. This research has investigated underground wireless propagation characteristics at UHF and microwave frequencies in tunnels. This has involved examining electromagnetic (EM) waveguide theory, in particular the lossy dielectric tunnel waveguide model e.g. (Emslie et al., 1975 and Delogne, 1982). Extensive tests have been carried out in three different underground locations (railway tunnel, hard rock mine, coal mine test facility) using continuous wave (CW), or ‘pure’ transmission at 2.3GHz and 5.8GHz, along with a range of throughput performance tests using various wireless technologies: IEEE 802.11b, 802.11g, SuperG, SuperG (plus BeamFlex antennas), 802.11pre-n. 802.11draft-n, and Bluetooth. The results of these practical tests have been compared with the lossy dielectric tunnel waveguide model showing good agreement that tunnels will in fact enhance the EM propagation through the waveguide effect. Building on previous research during the last 30 years into high frequency underground radio transmission, this work presents a novel investigation into the performance of modern underground wireless technologies operating in underground mines and tunnels. 4 The feasibility and performance of low power wireless mesh networking technology, relating to Zigbee/IEEE 802.15.4, operating in various underground and confined space environments has been investigated through a series of practical tests in different locations including: a hard rock test mine, a coal mine and a fire training centre (confined space built infrastructure). The results of these tests are presented discussing the significant benefits in employing ‘mesh’ topologies in mines and tunnels. Following this, key applications were identified for potential development. Distributed smart sensor network e.g. environmental monitoring, machine diagnostics or remote telemetry, applications were developed to a proof-of-concept stage. A remote 3D surveying telemetry application was also developed in conjunction with the ‘RSV’ (remote surveying vehicle) project at CSM. Vital signs monitoring of personnel has also been examined, with tests carried out in conjunction with the London Fire Service. ‘Zonal location information’ was another key application identified using underground mesh wireless networks to provide active tracking of personnel and vehicles as a lower cost alternative to RFID. Careful consideration has also been given to potential future work, ranging from ‘mine friendly’ antennas, to a ‘hybrid Zigbee’, such as, optimised routing algorithms, and improved physical RF performance, specifically for high-integrity underground safety and emergency applications. Both the tests carried out and key safety applications investigated have been a novel contribution of this thesis. In summary, this thesis has contributed to furthering the knowledge within the field of subsurface electromagnetic wave propagation at UHF and microwave frequencies. Key characteristics and requirements of an underground critical safety data transmission system have been identified. Novel aspects of this work involved investigating the application of new wireless mesh technology for underground environments, and investigating the performance of modern wireless technologies in tunnels through practical tests and theoretical analysis. Finally, this thesis has proved that robust and survivable underground data transmission, along with associated mine safety applications, can feasibly be achieved using the low power wireless mesh networking technology. Robust underground wireless networking also has potential benefits for other industrial and public sectors including tunnelling, emergency services and transport

On air: Evaluating streaming MPEG4 video performance over wireless networks [abstract]

Abstract only availableThere is not a clear consensus on how open-standard video streaming technologies perform across wireless computer networks. Wireless networking technologies have become nearly ubiquitous, particularly in residential networks, but consumers may not realize that the performance of wireless networks may differ significantly from that of wired networks. Advances in video compression and wireless network bandwidth may allow for the ability to stream higher-quality video content than previously possible. We seek to evaluate how video content, encoded by the MPEG4 codec, performs when streamed across simulated residential wired and wireless networks. We are interested in how the transmission of the video across the network link affects the subjective and objective appearance of the video on the client computer. Our network testbed comprises nine typical desktop computers equipped with a modified version of Videolan Client to playback a network video stream, provided by a server running the Darwin Streaming Server from Apple Inc., connected using wired Ethernet connections and 802.11b, 802.11g, and draft 802.11n version 1.0 wireless connections. Each client was monitored while receiving a sample of raw video data encoded at one of several common bitrates to note any lost content. Each client saved a copy of the video locally for later comparison with the original using the PSNR (Peak Signal to Noise Ratio) and SSIM (Structural SIMilarity) metrics. Looking strictly at established wireless standards (802.11b and g), we found that they are not capable of streaming multiple ITU-R BT.709 high definition video streams across a wireless network link. Wired and draft 802.11n wireless connections did prove robust enough to handle multiple high definition video streams concurrently. Hopefully, our work will lead to a better understanding of the technical issues, performance, and trade-offs in home networking, thus facilitating the rapid deployment of advanced home networking services and applications

A business planning framework for WiMAX applications

Mobile networking refers to wireless technologies which provide communications between devices. Applications for mobile networking have a broad scope as they can be applied to many situations in either industrial or commercial sectors. The challenge for firms is to better match market-induced variability to the organizational issues and systems necessary for technological innovation. This chapter develops a business planning framework for mobile networking applications. This framework recognises the fluidity of the situation when trying to anticipate and model emerging wireless applications. The business planning framework outlined in this chapter is a generic model which can be used by companies to assess the business case for applications utilizing mobile networking technologies

Smart Grid Communications: Overview of Research Challenges, Solutions, and Standardization Activities

Optimization of energy consumption in future intelligent energy networks (or Smart Grids) will be based on grid-integrated near-real-time communications between various grid elements in generation, transmission, distribution and loads. This paper discusses some of the challenges and opportunities of communications research in the areas of smart grid and smart metering. In particular, we focus on some of the key communications challenges for realizing interoperable and future-proof smart grid/metering networks, smart grid security and privacy, and how some of the existing networking technologies can be applied to energy management. Finally, we also discuss the coordinated standardization efforts in Europe to harmonize communications standards and protocols.Comment: To be published in IEEE Communications Surveys and Tutorial