The Research On The Key Algorithm Of Power Line Carrier Communication System Based On OFDM

Growing at an alarming rate in today's world informatization,information and communication has been as life and veins in today's world.Information communication between the mainly depends on the computer communication,and communication as a method of transmission and computing technology and sensor technology gradually become into a whole,has become a national and global economic growth engine in this century.In all kinds of mobile communication technology,OFDM(orthogonal frequency division multiplexing)as a kind of communication technology,has wide application prospect.Orthogonal frequency division multiplexing system with the method of inserting cyclic prefix,can be produced by multipath transmission intersymbol interference effect is reduced,and accurately estimate the channel characteristics,to reduce the influence of channel time-varying nature of the system.And,because its Fourier transform can greatly simplify the receiver,therefore,the use of OFDM technology in wireless communication which received widespread attention.But the OFDM system in the estimate of the channel parameters can easily lead to error and the error of the small systems appear serious mistakes easily,importance is based on channel estimation in OFDM technology becomes more significant.This article will focus on in the power line communication environment channel estimation and channel estimation algorithm of OFDM system.Articles on the block pilot based channel estimation algorithm for OFDM system,include: the LS algorithm,LMMSE algorithm and LR_LMMSE algorithm.Finally through the M language of MATLAB programming,simulation,created the OFDM system,a simulation model of the OFDM system anti-noise performance compared to the simulation results are studied.This topic on its own production and analysis based on orthogonal frequency division multiplexing(OFDM)technology of power line carrier communication system,and validate a powerline OFDM communication effect.This article first analysis of the current global nearly shape of low voltage power line carrier communication related research.The second chapter introduces the smart grid based on power line carrier communication,analyzed the OFDM technology implementation details of low voltage power line transmission.In the low voltage powerline OFDM communication system has been completed transmitter and receiver digital filter and synchronization algorithm was realized based on parts.Use has created good powerline OFDM communication system,adopt synchronous test,through the test on two different synchronization methods was compared.