目前Turbo码译码算法运算较复杂,无法满足LTE及LTE-Advanced的高速吞吐要求,因此,研究LTE环境下的Turbo码译码算法具有理论意义与工程价值。从降低译码延时考虑,评估各种迭代停止准则对性能及译码效率的影响,在分析外信息统计特性收敛的基础上,设计基于外信息收敛的双门限停止准则。仿真结果表明,改进的迭代停止准则在不影响译码性能的前提下,能较好地提高译码速率。
The current turbo decoding algorithm,for its very complex operation,couldn’t meet the high-speed transmission of LTE and LTE-Advanced systems.Therefore it is of great theoretical and practical importance to study the performance of turbo decoding algorithm in LTE systems.With considering the time delay of turbo decode algorithm the impact of several different iterations algorithm on the decoding performance is evaluated.Based on convergence statistic characteristics of the extrinsic information,the double threshold decoding algorithm is designed.Simulation results show that the double-threshold decoding iteration could improve the decoding speed effectively without obvious reduction of decoding BER performance.