围长较大的短码长准循环(QC)低密度奇偶校验(LDPC)码的显式构造对于QC-LDPC短码的理论研究与工程应用具有重要意义。首先提出一种基于成对策略的贪婪搜索算法,并根据此算法在列重J为4时的经验结果,归纳总结出一种具有双序列反序特征的...围长较大的短码长准循环(QC)低密度奇偶校验(LDPC)码的显式构造对于QC-LDPC短码的理论研究与工程应用具有重要意义。首先提出一种基于成对策略的贪婪搜索算法,并根据此算法在列重J为4时的经验结果,归纳总结出一种具有双序列反序特征的指数矩阵。随后证明了该指数矩阵对于任意行重L均对应于围长为8的QC-LDPC码。与现有的典型显式构造方法即最大公约数(GCD)方法相比,新QC-LDPC码提供的码长显著降低。最后,将指数矩阵的拆分拼接和掩膜处理技巧与新QC-LDPC码结合起来,设计出了译码性能在高信噪比区超过5G NR LDPC码的合成码。展开更多
A novel aliphatic sulfonie acid ion exchange resin was prepared from ethylenediamined polystyrene(PS-acyl-EDA),2-acrylamido-2-methylproanesulfonic acid(AMPS)by Michael reaction.This kind of resin has a longer chain th...A novel aliphatic sulfonie acid ion exchange resin was prepared from ethylenediamined polystyrene(PS-acyl-EDA),2-acrylamido-2-methylproanesulfonic acid(AMPS)by Michael reaction.This kind of resin has a longer chain than conventional sulphonic polystyrene resin,that is,the former is easier to react with other compound.The effect of the reaction time,reaction temperature,catalyst amount,reagent amount and the charge ration on reaction result were discussed.Under the optimum condition,the maximum loading of the sulfonie acid ion exchange resin could be up to 1.15 mmol·g-1 resin.The product was characterized with FT-IR.The filling material of chromatographic column could be prepared by this method.展开更多
文摘围长较大的短码长准循环(QC)低密度奇偶校验(LDPC)码的显式构造对于QC-LDPC短码的理论研究与工程应用具有重要意义。首先提出一种基于成对策略的贪婪搜索算法,并根据此算法在列重J为4时的经验结果,归纳总结出一种具有双序列反序特征的指数矩阵。随后证明了该指数矩阵对于任意行重L均对应于围长为8的QC-LDPC码。与现有的典型显式构造方法即最大公约数(GCD)方法相比,新QC-LDPC码提供的码长显著降低。最后,将指数矩阵的拆分拼接和掩膜处理技巧与新QC-LDPC码结合起来,设计出了译码性能在高信噪比区超过5G NR LDPC码的合成码。
文摘A novel aliphatic sulfonie acid ion exchange resin was prepared from ethylenediamined polystyrene(PS-acyl-EDA),2-acrylamido-2-methylproanesulfonic acid(AMPS)by Michael reaction.This kind of resin has a longer chain than conventional sulphonic polystyrene resin,that is,the former is easier to react with other compound.The effect of the reaction time,reaction temperature,catalyst amount,reagent amount and the charge ration on reaction result were discussed.Under the optimum condition,the maximum loading of the sulfonie acid ion exchange resin could be up to 1.15 mmol·g-1 resin.The product was characterized with FT-IR.The filling material of chromatographic column could be prepared by this method.