| Power line communication technology, which use the power line as communicationchannel to transmit information,is built on the basis of the existing low-voltage grid.High-speed PLC Internet access technolog has become a hot research field of Internetcommunication, because it has the properties of large coverage, throughout the urban andrural areas, direct conneting to the user comparing to the traditional communicationtechnologes, and known the most competitive techonolgy to solute ‘the last1km’ and ‘the last100m’ problem.Firstly, this paper detailed introduces the research and application status of PLCtechnology in the world, especially in the field of power industry, home automation and themain research content of this paper are put forward.Secondly the paper analyzes the characteristics of electric power line communicationchannel, including impedance characteristic analysis, noise analysis, the attenuation caused bymultipath propagation and delay, etc. The multipath channel transmission model, which is thebase of signal modulation techniques selecting, is analyzed, simulated and validated by usingMatlab simulation tools. Based on the research of spread spectrum technique and orthogonalfrequency division multiplexing technique, this system chooses OFDM as the signalmodulation technology.Subsequently, the hardware circuit and PCB of the high-speed PLC modem is designed.These works include: PCB pad design of PLC chip’s LFBGA packaging, PCB layers andlaminated mode selection, the layout design of the devices, in order to improve theelectromagnetic compatibility and thermal properties of the system. After fulfilling the systemthe design and manufacture of PCB circuit board, the basic properties of the system wastested and analyzed. |
