QC-LDPC Encoding And Decoding Algorithm In The Power Line Communication

It is a trend of home network that using existing families transmission media (such astwisted pair, coaxial cable, and power lines) to communicate without re-designing.G.hnstandard proposed by ITU is considered to be the next generation of home networkingstandard protocols. Power line communication as a new type of access network technologygets more and more attentions, but there are many issues to be resolved in the power linecommunication. There is a lot of impulse noise interference in power line communication,making communication difficult to guarantee the quality, so we need to introduce anexcellent channel coding techniques to suppress impulse noise interference.LDPC is most closest to Shannon limit in available method, so it can be introduced tocorrect the problem of high bit error rate due to the pulse noise. This paper first introducesthe basic concepts and features of the LDPC codes, and then analysis and research theQC-LDPC encoding method based on the G.hn protocol. In order to simulate the channelenvironment of the power line, we introduce of class A pulse noise to build models,through analysis of the existing method of decoding, given the adaptive decodingalgorithm based on the existing of the impulse noise and the structure of parity checkmatrix. Through simulation, found the method of adaptive decoding algorithm haveimproved on performance respect to the standard BP algorithm. Given several differentimplementations to solve the Rate-compatible because the time-varying channel.A impoved punching method suitable for G.hn protocol is proposed. And using Low bit rate matrixes to obtain two other types of matrixes with high bit rates by line transformation.The simulation results have verified their rationality.