Power line local area networking
暂无分享,去创建一个
he use of ubiquitous electrical wiring as a potential medium for communication signals has been suggested over past generations. Indeed, for some decades now, power line wires have been used for low-speed data communication, culminating in such standards and products as LonWorks, CEBus, and X-10, as well as many proprietary systems for the transmission of control and management signals. However, the power line has largely been dismissed as being too noisy and unpredictable to be useful as a practical high-speed communication channel. On the other hand, recent advances in communicat ion and modulation methodologies, as well as in adaptive digital signal processing and error detection and correction, have opened the way for the development of effective medium access control and physical layer protocols that support power line communications (PLC) networks operating at speeds comparable to those obtained from specially wired and more recent wireless local area networks. In mid-2001, an industrial standards organization called the HomePlug Powerline Alliance, originally founded by 13 companies including Cisco, Motorola, Intel, Panasonic, and Texas Instruments, announced the completion of the HomePlug 1.0 specification for a 10 Mbis class in-home power line networking technology based on orthogonal frequency-division multiplexing (OFDM). Products based on this industry standard are enjoying much positive attention in the market press from industry and product analysts based on performance and ease of use. It was clear at the January 2003 Consumer Electronics Show that HornePlug is now recognized as one of three attractive in-borne networking solutions, together with Ethernet and Wi-Fi (IEEE 802.11~). The HomePlug Powerline Alliance recently announced an effort to establish a 100 Mbis class in-home power line networking standard, called HomePlug AV, to provide distribution of data and multistream video and audio, including high-definition television (HDTV) throughout the home. Measurements and analysis of in-home power line channel capacity demonstrate that this goal is fe.asible. This new technology will be well positioned to revolutionize in-home entertainment networking by providing a simple, reliable, and cost-effective solution for consumer products such as personal video recorders, media centers, and flat panel televisions. In addition to developments associated with in-building PLC LANs, progress has also been made in the use of the powerline as an alternative to DSL and cable modems for broadband Internet access. The purpose of this feature topic in IEEE Communications Magazine is to highlight and document the significant progress in high-speed digital communication over power lines that is precipitating a new genre of wired local area and access networks requiring no new or specialized wiring. There are five articles in this series of articles. The article “Power Line Communications: State of the Art and Future Trends” by Niovi Pavlidou, Han Vink, Javad Yazdan, and Bahram Honary gives an overview on the history of PLC as well as a description of ongoing research, applications, regulatory activities, market perspectives, and