一种改进的堆栈译码算法

An Improved Stack Decoding Algorithm

深太空通信对编译码的性能有十分高的要求,卷积码的性能和约束长度密切相关,约束长度越大卷积码的编码增益越大,则其性能越好。维特比译码算法由于受译码开销的限制,并且其译码开销随约束长度增加呈指数增长,维特比译码算法仅适用于短约束长度的卷积码。目前仅有序列译码算法适用于大约束长度卷积码译码。由于堆栈译码算法中堆栈的大小是有限的,在信道受扰较为严重的情况下,潜在的正确路径有可能被删除,这将影响到译码的性能。多堆栈译码算法不存在潜在删除的问题,多堆栈译码算法完成译码所需计算量远小于堆栈译码算法。

Deep Space Communication have very high requirements on the performance of the complied code , the performance a is closely related to the constraint length of convolutional code, grea- ter constraint length convolutional coding gain is larger, the better its performance. Viterbi decoding algorithm due to limited by coding overhead, and its decoding overhead increases exponentially with the increase of constraint length, Viterbi decoding algorithm is only suitable for short constraint length of the convolutional code. Currently the only suitable for large constraint length convolutional decoding algorithm is sequence decoding. Due to the size of the stack in the stack decoding algorithm is limited, in the ease of channel disturbance of serious, potential right path may have been deleted, which will affect the performance of the decoding. The multi - stack decoding algorithm doesnt have the problem of deleting the potential path, and its needed to complete the decoding computation is far less than stack decoding algorithm.