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本文根据章照止所提供的造码方法,用计算机构造了若干适用于序列译码的多准则兼优(2,1,31)和(3,1,31)非系统卷积码,并列出了部分码的生成元。其最小距离d_c(m)、列距离分布d_c(0,h)均达到最优。(2,1)码的自由距离d_f可高达29～30,(3,1)码的d_f达47～49。本文所列出的多准则兼优码全部是非透晰的。它还具有最大反列距离d_c(m)。因此在序列译码中使用后,将降低识别180°相位模糊度所需的计算量。本文列出的(3,1,31)非系统码具有1/2、1/3两种编码速率兼优的特性。
In this paper, according to the coding method provided by Zhang Zhaozhi, a number of non-systematic convolutional codes with multi-criteria and good (2,1,31) and (3,1,31) Generated part of the code generator. The minimum distance d_c (m), column distance distribution d_c (0, h) are the best. The free distance d_f of (2,1) yards can be as high as 29-30, and the d_f of (3,1) yards can reach 47-49. The multi-criteria and good codes listed in this article are all non-transparent. It also has a maximum anti-column distance d_c (m). Therefore, when used in sequence coding, the amount of computation needed to identify 180 ° phase ambiguities will be reduced. This article lists (3,1,31) non-systematic code with 1/2, 1/3 coding rate and excellent characteristics.