Study On Channel Coding In Erasure Channel And Meteor Burst Channel

Low-Density Parity-Check (LDPC) codes are a class of capacity approaching error-correcting codes. Due to the advantages of LDPC codes, their applications in reliablecommunications have received great interests and have become one of most attractivefield in channel coding community.In this dissertation, the author took LDPC codes as the primary research object,mainly studied the channel coding problems in erasure channel and in meteor burst chan-nel. The author obtains main results as follows:About the coding scheme in erasure channel,(1) The low-density erasure codes and digital fountain codes are introduced. The ap-plication of digital fountain codes in network is summarized. The existing problemsand prospect are also given.(2) The asymptotic bound of systematic regular RA codes and CT codes is calculated.Theoretic and simulation results show that the degree choice will a?ect largely onthe performance of systematic regular RA codes while less on the on the performanceof systematic regular CT codes.(3) The degree polynomial of the low-density erasure codes is introduced and the con-dition of the successful recovering for the low-density erasure codes is given. A newdegree polynomial which can accord with the condition is proposed.(4) The SR-LDPC code is introduced using graph model and parity-check matrix. Therateless character of the SR-LDPC codes is analyzed, and the capacity achievingcharacter of the SR-LDPC codes is verified in theory and simulation results.About the coding scheme in meteor burst channel,(5) The advanced channel coding method in meteor burst channel is proposed. Simula-tion results show that the advanced channel coding can be applied in meteor burstcommunication. Some principles and conclusions of LDPC codes used in meteorburst communication are given.(6) A kind of semi-irregular LDPC codes suitable for meteor burst communication ispresented. Simulation results show that the application of this kind of semi-irregularLDPC codes in meteor burst communication yields better performance than theregular ones. Some theoretical analysis are given. (7) Considering the properties of meteor burst channel, a novel Channel Coding scheme,multilayer coding scheme, is provided. Some simple simulation result about it is alsogiven.