Research On The Power L~2C~2

We show our attention on the PowerLine Communication technology greatly now, which uses the power line as a communication media to create a high speed data channel and supply services such as high speed Internet access and create great economic and social profit. Using the technology, we can get a broad band access within a rang of the distribution transformer as well as a home LAN through outlet of every house. It's a complementarity and extent of other broad band access method. As the high speed power line communication uses the intrinsic powerline and the number of power users of 220V is much larger than that of CATV and ADSL, this technology has a large number of latent users.This article discusses the low-voltage power line carrier communication basic overview firstly. Including its development and applications in the future, and keep the unique in the field of related technology and research, and major technical difficulties, problems and solutions in the achievement of low-voltage power line carrier communication And then provides an overview of the status of their research at home and abroad. Then this article study the low-voltage power line as a transmission medium of communication channel characteristics, such as the changes of input impedance characteristics, signal characteristics and noise attenuation properties.The low-voltage power line is designed for the transmission of electricity, but it is not a very good communication channel for data communication. In order to make the high-speed data signals communicate on low-voltage power line reliably, not only the transmission channel characteristics of the low-voltage power line should be analysised, but also appropriate modulation technology should be chosen for the low-voltage power line communication. In the low-voltage power line carrier communications, the most prominent is the spread spectrum communication technology and orthogonal frequency division multiplexing (OFDM) technology. These two technologies have the ability of strong anti-jamming, anti-multi-path effects to apply well in the special environment of the power line communications. In this paper, two communication technologys have been analysised and proved that OFDM technology is more suitable for low-voltage power line carrier communications.After the related theory analysis, the thesis introduced the Intellon's INT5200 and KS8721SL particularly, and then it presented the design proposal for the whole system and also made every functional module actualized part by part. In this paper, it accomplished the whole designing, hardware making and obtained some data and experience valuable based on MATLAB. According to the design and analyses of the whole paper, it proved that, with the OFDM technology, high-speed communication on the low-voltage powerline is really practicable, and it certainly will lead to a more widen application prospect with realistic meaning.