格雷码的代数软判决译码研究

Algebraic soft-decision decoding of Golay codes

基于可靠性译码的Chase II算法实现了Golay码的软判决译码,获得了比代数硬判决译码更优的纠错性能,也因此提高了译码的复杂度,增加了译码延时。基于此,引入最优性条件,以快速终止Chase译码。通过VC6.0仿真,结果表明,在BER=10-5时,代数软判决相比硬判决有1.7 dB的性能增益,加入最优性条件以后,总的仿真时间比传统的Chase II算法节省了约87.64%,极大地提升了软判决译码的效率。

In this paper, the Chase Ⅱ algorithm,which is well known as a reliability-based decoding algorithm, is used for the soft decoding of the（ 23, 12, 7 ）Golay code. This soft-decision decoding algorithm improves greatly the error-correcting capacity compared with algebraic hard-decision decoding algorithms, hut also results in more computational complexity. To overcome this, a optimality condition is introduced to quickly terminate the Chase Ⅱ decoding process. Computer simulation results got by VC6. 0 show that soft decoding obtains 1.7 dB coding gain compared with hard decoding case at BER of 10 -s, and the modified chase-Ⅱ algorithm based on the optimality condition reduces the total simulation time by 87.64% , and thus improves greatly the decoding efficiency.