论文标题
多用户通信的整数环上的双重反复蓄电代码
Doubly-Irregular Repeat-Accumulate Codes over Integer Rings for Multi-user Communications
论文作者
论文摘要
证明基于晶格的结构化代码可为多用户通信网络提供扩大的能力。在本文中，我们研究了能力 - 取决于整数环上的不规则重复累积（IRA）代码$ \ MATHBB {Z} _ {2^{M}} $，$ 2^m $ -PAM信号，$ m = 1,2，\ cdots $。此类代码具有$ k $ codeWords的整数和属于扩展代码簿（或晶格）W.R.T.的属性。基本代码。有了它，可以利用\ emph {％结构化binning}，并且可以在基于晶格的网络信息理论中承诺的收益在实践中实现。在设计IRA环形码时，我们首先分析了整数环的零分差对迭代信念传播（BP）解码的影响，并显示了对称高斯近似值的无效性。然后，我们提出了一个双重IRA（D-ira）环形代码结构，该结构由\ emph {不规则的乘数分布}和\ emph {不规则的节点分布}组成，可以恢复对称性并优化BP解码阈值。对于具有$％2^m $ -PAM输入的点对点AWGN通道，D-IRA环形代码的性能低至0.29 dB，对容量限制的表现优于现有的位于位置的编码模块（BICM），而IRA调制代码超过了GF（$ 2^m $）。然后，我们继续为两个重要的多用户通信设置设计D-ira环代码，即计算 - 前向（CF）和肮脏的纸质编码（DPC），并带有$ 2^M $ -PAM信号传导。借助它，物理层网络编码方案会导致CF限制的差距为0.24 dB，而简单的线性DPC方案则表现出0.91 dB的差距。
Structured codes based on lattices were shown to provide enlarged capacity for multi-user communication networks. In this paper, we study capacity-approaching irregular repeat accumulate (IRA) codes over integer rings $\mathbb{Z}_{2^{m}}$ for $2^m$-PAM signaling, $m=1,2,\cdots$. Such codes feature the property that the integer sum of $K$ codewords belongs to the extended codebook (or lattice) w.r.t. the base code. With it, \emph{% structured binning} can be utilized and the gains promised in lattice based network information theory can be materialized in practice. In designing IRA ring codes, we first analyze the effect of zero-divisors of integer ring on the iterative belief-propagation (BP) decoding, and show the invalidity of symmetric Gaussian approximation. Then we propose a doubly IRA (D-IRA) ring code structure, consisting of \emph{irregular multiplier distribution} and \emph{irregular node-degree distribution}, that can restore the symmetry and optimize the BP decoding threshold. For point-to-point AWGN channel with $% 2^m $-PAM inputs, D-IRA ring codes perform as low as 0.29 dB to the capacity limits, outperforming existing bit-interleaved coded-modulation (BICM) and IRA modulation codes over GF($2^m$). We then proceed to design D-IRA ring codes for two important multi-user communication setups, namely compute-forward (CF) and dirty paper coding (DPC), with $2^m$-PAM signaling. With it, a physical-layer network coding scheme yields a gap to the CF limit by 0.24 dB, and a simple linear DPC scheme exhibits a gap to the capacity by 0.91 dB.
