Bandwidth efficient multilevel coded modulation system based on ldpc codes is described in the last part of this thesis . furthermore , the designing method of combining component code rate and degree distribution is introduced 介紹了ldpc碼的多層編碼調(diào)制系統(tǒng)中,分量碼碼率與度序列分布聯(lián)合最優(yōu)的設(shè)計(jì)準(zhǔn)則,并給出了相應(yīng)的理論分析。