LT Codes差错平台(Erasure Floor)由变量节点的最小度决定,规则变量节点度LT Codes能够最大化变量节点的最小度,从而降低LT Codes的差错平台。该文提出一种新的规则变量节点度LT Codes编码方法,该编码方法省去了现有方法中对变量节点度值查找表的排序操作,降低了现有方案的编码复杂度;通过对度分布的修正增加低度校验节点,使得规则变量节点度LT Codes解码瀑布区域(雪崩区域)提前。仿真结果表明该文方法与现有方法相比有效减少了编码时间,降低了成功解码所需的平均传输开销,加快了误符号率收敛速度。%The erasure floor of LT Codes is mainly determined by the minimum degree of variable-nodes .Regular variable-node degree LT Codes can maximize the minimum degree of variable-nodes and improve the erasure floor of LT Codes .In this pa-per ,a novel encoding scheme for regular variable-node degree LT Codes is proposed .Compared with existing methods ,the proposed scheme is lightweight due to the elimination of the sorting operations involved in the look-up table .Meanwhile ,by adding check nodes with low degree through modifying the degree distribution ,the waterfall area (avalanche area ) in decoding regular variable-node degree LT Codes is improved .Simulation results show that this scheme reduces the encoding time and the average overhead , and accelerates the convergence rate of symbol error rate curve efficiently .
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