发表机构
Politecnico di Torino; Soochow University（都灵理工大学; 苏州大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对含异构跨段等复杂结构的多波段WDM系统，提出高效的相关性GN模型（cGN），可高精度计算NLI频谱，且已作为免费软件发布。
AI 中文摘要
在包含异构跨段和非相同信道的多波段WDM系统中，准确且计算高效地评估非线性干扰（NLI）仍然是一项挑战。此类系统中，信道可能具有不同的空间功率分布和多子载波结构；跨段可能使用不同的光纤类型，具有跨段相关的色散和损耗分布；还可能采用包括前向和后向拉曼放大在内的通用放大方案，同时存在信道间受激拉曼散射以及多个集总增益或损耗元件。在这一全面框架下，我们对GN模型的NLI贡献进行了高效分解，表明WDM梳状谱上任意频率处的NLI功率谱密度根本上由信道空间功率分布的空间自相关和互相关驱动，或等效地由相应的能量谱驱动，因此将该形式体系命名为“相关性GN模型”（correlation GN-model，简称cGN）。一旦计算出这些相关性或能量谱，剩余计算可简化为快速、行为良好的一维数值积分。此外，cGN充分考虑了每对跨段中NLI的相干性，而现有分析和半分析GN模型公式常忽略或近似该相干性，尽管它可使NLI增加数dB。简言之，cGN框架适用于任意波段、任意带宽的通用系统，计算效率极高，能够提供每个信道或多个子载波上多个频率处的NLI频谱，且因几乎未引入任何近似而精度极高。该cGN框架可从欧盟Zenodo网站作为免费下载软件获取。
英文摘要
Accurate and computationally efficient evaluation of non-linear interference (NLI) remains challenging in multi-band WDM systems comprising heterogeneous spans and nonidentical channels. In such systems, channels may have distinct spatial power profiles and multi-subcarrier structures. Spans may use different fiber types with span-dependent dispersion and loss profiles. These systems may further employ general amplification schemes, including forward and backward Raman amplification. Inter-channel stimulated Raman scattering and multiple lumped gain or loss elements may also be present. In this encompassing framework, we provide an efficient decomposition of the GN-model NLI contributions. We show that the NLI power spectral density at any frequency across the WDM comb is fundamentally driven by the spatial auto- and cross-correlations of the channels' spatial power profiles or, equivalently, by the corresponding energy spectra. For this reason we call this formalism the `correlation GN-model', or cGN. Once these correlations or spectra have been computed, the remaining calculations reduces to a fast, well-behaved one-dimensional numerical integral. Moreover, cGN fully accounts for coherent interference of NLI in every pair of spans. Such coherence is often neglected or approximated in existing analytical and semi-analytical GN-model formulations, although it can increase the NLI by several dB. In short, the cGN framework applies to any general systems over any band and any bandwidth, with very high computational efficiency. It is capable of providing the frequency spectrum of NLI at multiple frequencies across each channel or subcarrier. Its accuracy is very high because virtually no approximations are invoked. The cGN framework is available as freely downloadable software from the European Union Zenodo website.
CommentsThe paper is identical to a manuscript submitted to JLT in October 2026
