Ofdm Power-line Communication Design Based On Fpga

PLC refers to the data transmission and information exchange over power line. It develops rapidly with the development of digital signal processing technology. Multi-carrier modulation has taken place of traditional single-carrier modulation so that transmission rate has significantly increased.nowadays, PLC has been studying in many areas such as smart home networking, broadband access and so on because of its advantages of no re-wiring and low cost.The paper describes the development status and trends of PLC technology in domestic and aboard, introduces a new way to solve it. Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier modulation technique and also a kind of multiplexing using a number of mutually orthogonal subcarriers to transmit information, it can not only greatly improves the spectrum efficiency, but also overcomes the frequency selective fading and multi-path delay in power line.which can achieves data communication high-speed and reliably.The paper focuses on how to establish a low-power line communication system based on OFDM. First the agreement of physical layer and media access control layer in power line network communication protocol HomePlug1.0is briefly introduced. Then, the principle of OFDM modulation and demodulation techniques is given. At last, the FPGA (Field Programmable Gates Arrays) implementation scheme based on OFDM is proposed. The FPGA implementation structure (described with VHDL) of the key modules are showed, such as RS module、IFFT module and DQPSK module. The function simulations of these modules are also finished.Meanwhile, peripheral configures high speed A/D、D/A, achieve analog-to-digital signal conversion and produces the circuit printing board.Under laboratory conditions, the paper tests the system via serial debugging tools. The results show that the system achieves the desired design goals. The improvement measure is also proposed.