Application Of OFDM Technology For HV Powerline Communications

Power Line Carrier (PLC) has been widely used in the electrical industry for transmitting voice and tele-control signals through powerline. Digital modulation and demodulation techniques are the principal breakthrough in powerline communications. In this paper, we present the results of our investigation into the BER performance of a digital multiplexer for powerline communication using OFDM technique.OFDM technology is a hot subject for high-speed data transmission in powerline communication field. Using FFT and IFFT transform, the operations of modulation and demodulation are accelerated in OFDM system. This makes itself suitable for DSP implementation.As the first step, we pick out suitable parameters to build the OFDM simulation platform. There are 9 selectable baud rates ranging from 2.4kbps to 21.6kbps. In research of OFDM modem, some topics are further discussed, such as timing synchronization, constellation rotation.For remote-control data transmission, three methods are proposed in FSK demodulation, including phase detection, correlation and recursion. Simulation results show that recursion technique has lower complexity and better performance.In particular, the relationship between Signal Noise Ratio (SNR) and Bit Error Rate (BER) are analyzed through a simulated AWGN channel. Error Correction Code and interleave techniques are also evaluated in remote-control communications.