As a class of convolutional-based low-density parity-check (LDPC) codes, spatially coupled protograph (SC-P) codes not only can exhibit outstanding error performance but also can realize low-complexity implementation. Motivated by the prominent superiorities, SC-P codes have been intensively investigated in various communication environments. However, no research works regarding SC-P codes in the magnetic recording (MR) scenarios have been done so far. To explore such an issue mentioned previously, this article carries out a comprehensive study on the SC-P codes in the two-dimensional magnetic recording (TDMR) systems. Specifically, a turbo-like extrinsic information transfer (EXIT) algorithm is conceived for the SC-P-coded TDMR systems. With the help of such an algorithm, we evaluate the convergence performance (i.e., decoding thresholds) for conventional SC-P codes over TDMR channels with turbo equalization and illustrate that such codes should be re-constructed to attain better performance. Therefore, we develop an optimization scheme to generate a novel class of SC-P codes, called enhanced SC-P codes, which can exhibit promising decoding thresholds without losing the linear-minimum-distance superiority. The convergence-performance analyses and simulated results reveal that such enhanced SC-P codes can obtain more desirable coding gains in contrast to the conventional SC-P codes and the state-of-the-art protograph codes for the whole signal-to-noise-ratio (SNR) range under study. The excellent performance and simple implementation make the enhanced SC-P codes a very competitive error-correction solution for the next-generation TDMR devices.

中文翻译：

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二维磁记录系统空间耦合低密度奇偶校验码的性能分析与优化

作为一类基于卷积的低密度奇偶校验（LDPC）码，空间耦合原图（SC-P）码不仅可以表现出出色的错误性能，而且可以实现低复杂度的实现。在突出优势的推动下，SC-P 码在各种通信环境中得到了深入研究。然而，到目前为止，还没有关于磁记录 (MR) 场景中的 SC-P 代码的研究工作。为了探讨前面提到的这个问题，本文对二维磁记录（TDMR）系统中的SC-P码进行了全面的研究。具体来说，为 SC-P 编码的 TDMR 系统设想了一种类似涡轮增压的外在信息传输 (EXIT) 算法。在这种算法的帮助下，我们评估收敛性能（即，解码阈值）用于 TDMR 信道上具有涡轮均衡的传统 SC-P 代码，并说明应该重新构建此类代码以获得更好的性能。因此，我们开发了一种优化方案来生成一类新的 SC-P 码，称为增强型 SC-P 码，它可以在不失去线性最小距离优势的情况下表现出有希望的解码阈值。收敛性能分析和模拟结果表明，与传统的 SC-P 码和最先进的全信噪比的原型码相比，这种增强的 SC-P 码可以获得更理想的编码增益。 -比率（SNR）范围正在研究中。卓越的性能和简单的实现使增强型 SC-P 码成为下一代 TDMR 设备极具竞争力的纠错解决方案。