Since last decade, Spectral Amplitude Coding Optical Code Division Multiple Access (SAC-OCDMA) system has become popular since it offers security, unlimited bandwidth and eliminates multiple access interference. On the other hand, Free Space Optics (FSO) provides last-mile access at a high data rate. We have designed a new zero cross-correlation code, which is named as an identity-type matrix ZCC code. The proposed code’s performance is evaluated by designing 120 GB/s Hybrid FSO-MDM (mode division multiplexing) and SAC-OCDMA system under atmospheric turbulence using the direct detection (DD) technique. Six channels, carrying 20 GB/s data each, are transmitted over the FSO channel. Two Laguerre Gaussian modes (LG 00 and LG 01) are used in MDM. The results of the simulation show that the performance of the proposed code is better in comparison to existing codes.

中文翻译：

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使用新设计的 ITM-零互相关码对 120 GB/s 混合 FSO-SACOCDMA-MDM 系统进行性能评估

自过去十年以来，频谱幅度编码光码分多址 (SAC-OCDMA) 系统因其安全性、无限带宽和消除多址干扰而变得流行。另一方面，自由空间光学 (FSO) 以高数据速率提供最后一英里访问。我们设计了一种新的零互相关码，称为恒等型矩阵 ZCC 码。通过使用直接检测 (DD) 技术在大气湍流下设计 120 GB/s 混合 FSO-MDM（模分复用）和 SAC-OCDMA 系统来评估所提出的代码的性能。通过 FSO 通道传输六个通道，每个通道承载 20 GB/s 的数据。MDM 中使用了两种拉盖尔高斯模式（LG 00 和 LG 01）。