Power Line Carrier Communication Module Hardware Design

The greatest advantage of the power-line network is that it covers a very wide range. Various buildings have power lines access. Different from the common internet, the PLC (Power-line communication) is not a long-distance correspondence, but the "last mile"communications access.The characteristic of channel, the mode of modulation and the methods of signal processing are main research contents in PLC. The characteristic of channel is the basic of PLC research, including the transmission lines, channel noise, and attenuation. The ability of anti-jamming, speed and distance of transmission are decided by the mode of modulation. For example, the FSK, BPSK, CDMA and OFDM are main modulations in the PLC. The signal processing can ensure and improve the performance of PLC, the main methods include filter, data coding, error correction, etc.Firstly, the characteristic of power line channel is discussed from the transmission lines, noise, and channel attenuation in this paper. And a project of power line communication in the short distance of a house is presented. Then, the design of the power line communication module based on that project is expounded in detail. From the results of the experiments, the design of hardware is proved right, and some new methods that can improve the performances of FSK PLC are presented at last in this paper.The design of PLC module and the experiments are emphases of this paper. The interface of power line, modem and controller are main parts of the module. With the experiments, the results are satisfied.In this paper, two novel signal processing methods based on quadrature processing and wavelet transform are proposed to improve the performances of normal FSK PLC. The results of simulations show that these improvements are valid and effective.