Research On Low Voltage Power Line Wave Carrier Communication System And The Technique For Noise Limiting

The Power Line Communication (PLC) is a kind of rising communication mode differing from traiditional communication such as telecommunication, telephone, radio communication, etc., in that the PLC transfers data and exchanges information by means of power line network. As a kind of universal physical media in every family, the prospect of the PLC communication is bright.The problem of noise is a chief block to restrict the popularity and developement of the PLC because of the irregularity of power line network, the randomness of transmission distrance and load facility diversities.This paper mainly focuses on the noise limiting by means of the Direct Sequence Spread Spectrum(DSSS) and the analysis of the transmission performance of the PLC and some digital modulation technology. The contents of the paper is as follows:1) The technical feasibility is proved after simulating noise limiting principle of DSSS by means of SystemView, the simulation software;2) A kind of Band Pass Filter(BPF) is realized according to the requirement of filter and the principle of ButterWorth approximation ,which satisfies the index of performance of DSSS.3) The low voltage PLC system includes the SC1128, the specific modulation/demodulation IC ,the BPF filter and other circuit components, furthermore, the control function of system is realized by means of the personal computer and the microcontroller.4) The experiment results have confirmed the effectiveness of DSSS technique for the PLC.