...
【24h】

How to Construct Polar Codes

机译:如何构造极地代码

获取原文
获取原文并翻译 | 示例
           

摘要

A method for efficiently constructing polar codes is presented and analyzed. Although polar codes are explicitly defined, straightforward construction is intractable since the resulting polar bit-channels have an output alphabet that grows exponentially with the code length. Thus, the core problem that needs to be solved is that of faithfully approximating a bit-channel with an intractably large alphabet by another channel having a manageable alphabet size. We devise two approximation methods which “sandwich” the original bit-channel between a degraded and an upgraded version thereof. Both approximations can be efficiently computed and turn out to be extremely close in practice. We also provide theoretical analysis of our construction algorithms, proving that for any fixed $varepsilon > 0$ and all sufficiently large code lengths $n$, polar codes whose rate is within $varepsilon $ of channel capacity can be constructed in time and space that are both linear in $n$.
机译:提出并分析了一种有效构造极性码的方法。尽管明确定义了极性码,但是直接构造很棘手,因为生成的极性位通道的输出字母随编码长度呈指数增长。因此,需要解决的核心问题是,用具有可管理字母大小的另一个信道忠实地逼近具有难以理解的大字母的比特信道。我们设计了两种近似方法,将原始位通道“三明治”在其降级版本和升级版本之间。这两个近似值都可以有效地计算出来,并且在实践中非常接近。我们还提供了构造算法的理论分析,证明对于任何固定的 $ varepsilon> 0 $ 以及所有足够大的代码长度 $ n $ ,比率在 可以在时间和空间中构建通道容量的$ varepsilon $ ,它们在 $ n $ < / formula>。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号