具有不等差错保护特性的Raptor码研究

Research on Raptor Codes with Unequal Error Protection Property

提出一种新的构造具有不等差错保护（UEP）特性的Raptor码方案,联合优化UEP-LDPC码和UEP-LT码改善重要信息比特（MIB）的性能,推导了构造码在二进制删除信道（BEC）上的密度进化（DE）公式.使用DE公式,优化了构造的UEP-Raptor码.仿真结果表明,相比UEP-Raptor码,作者构造的码对MIB和次要信息比特（LIB）都能提供更好的性能.

This paper proposes a new scheme to construct Raptor codes that can provide unequal error protection（UEP）property.It utilizes joint optimization of UEP-LDPC codes and UEP-LT codes to improve the performance of more important bits （MIB）.The density evolution （DE） formulas over binary erasure channels （BEC）are derived.By using the DE formulas,the constructed UEP-Raptor codes are optimized.Simulation results show that,compared with the previous UEP-Raptor codes,the proposed UEP-Raptor codes can get better performances of both MIB and less important bits （LIB）.