Research And Realization On Signal Processing Of DSP-based Power Line Carrier Communication

As an indispensable means of communication for Power system, power line carrier communication in China is an ancient and young subject. However, traditional analog devices can not fully meet the current market requirements for communication quality. The paper discusses the development and application of power line carrier communication technology. Aiming at enhancing the high speed and reliability of the communication on high voltage power line, two schemes:digital single sideband and TCM are proposed. Weaver modulation and IWA demodulation are selected to realize SSB, so that the phase deviation can be avoided. The sample rate conversion adopts multi-level technology and multi-item filtering structure, so can lighten the difficulty of filter design and the limited effect of word length, and greatly reduce the amount of computing and storage requirements. Considering the practical application environment, the improved Gardner symbol synchronization algorithm is put forward for timing synchronization in this paper. The combination of decision feedback carrier restoration loop and adaptive equalizer is adopted to eliminate the carrier frequency and phase restoration and channel distortion. Viterbi algorithm is used for decoding and error correction.With TMS320C6416DSP as the core component, a common signal processing hardware platform of power line carrier communication is designed in the paper. Around the DSP system architecture, EDMA, McBSP and EMIF are applied to build a framework for the system. Ping-Pong technique, the concrete peripheral interface configuration for real time digital stream transmission and interrupt processing are also detailedly introduced. Through analysis of simulation results and system testing,the performance of these two solution schemes mentioned above is verified, and ways to improve further are proposed.