The Research And Realization Of Broadband Powerline Carrier Communication Unit Based On Homeplug Green PHY

With the rapid development of communication technology, the research of power line carrier communication gets more and more attention. As an existing media, power line is ubiquity. Therefore, State Grid Corporation of China puts forward to build smart grid as a development strategy.Power line carrier communication is a communication way that we use the existing power line network to transfer signal, which can transfer a long distant and has a reliable(stable) channel, and can keep pace with the power grid construction. There is a huge application prospect and economic value in high speed data transmission via power line channel. But power line has some characteristics, such as unanticipated noises, multipath effect and selective fading channel, which seriously impact high speed data transmission. Hence, the research of channel characteristic of low voltage power line carrier communication is essential to the whole communication system research. Especially the research and simulation of channel noises has significant meaning.In this paper, we first summarize the development of power line carrier communication technology, and emphasize on the advantage of broadband power line carrier communication technology in remote meter reading system. Then the paper introduces HomePlug Green PHY protocol, especially its HPY and MAC layers, and explains the principle and implementation of OFDM (orthogonal frequency-division multiplexing). The paper analyzes that the OFDM technology has good performance in interference immunity, reducing multipath interference and anti-attenuation, which can overcome the harsh power line channel environment, and it has important effect on the development of power line communication. After that, the paper presents the characteristics of power line channel, and uses a considerable amount of descriptions on noise characteristic and multipath effect, and builds a OFDM system power line channel model by MATLAB software. Through analyzing the functional requirement of broadband power line communication unit, we use Greenvity Corporation's GV7013 chip that based on HomePlug Green PHY, to design the hardware and software of broadband power line carrier communication unit. This communication unit is used to achieve automated meter reading function of remote metering system. In the end, according to the protocol of State Grid and HomePlug Green PHY, we also design some test method to test the communication unit we have already produced, and the test result is followed, which prove the communication unit we have designed meets with our expected requirements.