Spectral-spatial coding and turbulence-aware modulation strategies for ultra-reliable dense WDM hybrid MIMO-RF free space optical communication networks
-
Ahmed H. Abbas
and
Zainab N. Jameel
Abstract
A turbulence flexible hybrid communication structure that adds free space optical (FSO), multi-output (MIMO) and dense wavelength division multiplexing (DWDM) links with an adaptive radio frequency (RF), presented in this article. In order to reduce turbulence and gesture to reduce atmospheric losses such as gamma-old, a two-layer spectral-sustainable coding form and disturbance-zeal adaptive modulation are suggested. Continuous coupling accessibility and reliability are ensured by dynamic switching of the system between optical and RF paths based on real-time information (CSI). Bit error rate (BER) is confirmed by Monte Carlo simulation in MATLAB. During the strong disturbance, the proposed architecture holds less than 10−3, while under weak disturbance it maintains more than 4 bits/s/Hz. According to the results, “the proposed architecture is a strong candidate for future back-hauls with high capacity, satellites and final-meal access networks applications such as the spectral stable variety and integration of adaptive modulation increases the strength of the system in unfavorable optical wireless conditions since the integration of intermediate diversity conditions.
Acknowledgments
Would like to express my grateful thanks to my parents for their support, kindness and patience in all and every stage of my life. They devoted their heart and soul to advance my education and encourage me to love learning and hardworking.
-
Research ethics: The corresponding author declares that this manuscript is their own work, and has not been published before in any journal and/or conference, and it is never been considered for publication or submitted to any other journals.
-
Author contributions: NJJ proposed the study of the manuscript, and MYM gave a valuable revision and illustration of some concept. ZFA wrote the article and suitable editing, and reading, and approved the final version.
-
Conflict of interest: The author states no conflict of interest.
-
Research funding: None declared.
-
Data availability: Not applicable.
References
1. Ibrahim, ZH, Jihad, NJ. J Opt. Performance study of different dispersion compensation schemes: review. New Delhi: Advance online publication; 2025.10.1007/s12596-025-02556-3Search in Google Scholar
2. Sabri, AA, Jihad, NJ, Hadi, WAH. Performance analysis of different dispersion compensation techniques in optical fiber communications system. J Opt 2024. https://doi.org/10.1007/s12596-024-01682-8.Search in Google Scholar
3. Jihad, NJ, Abd Almuhsan, MA. Implementation of various screen to camera techniques for optical OFDM communications systems. J Opt 2024. https://doi.org/10.1007/s12596-024-02354-3.Search in Google Scholar
4. Benton, DB, Li, Y, Billaud, A, Ellis, A. Spatial mode division multiplexing of free-space optical communications using a pair of multiplane light converters and a micromirror array for turbulence emulation. Appl Opt 2024;63:E15–23.10.3390/photonics11030241Search in Google Scholar
5. Jihad, NJ. Comparison between various dispersion compensation schemes in optical fiber communication system. J Opt Commun 2023:s1143–8. https://doi.org/10.1515/joc-2022-0295.Search in Google Scholar
6. ZH Ibrahim, NJ Jihad, ZN Jameel, Mitigation of the problem of dispersion in optics communications systems, J Opt Commun., . 14, 2025, https://doi.org/10.1515/joc-2025-0053.Search in Google Scholar
7. Fried, DL, Belsher, J. Analysis of fundamental limits to artificial-guide-star adaptive-optics-system performance for astronomical imaging. Appl Opt 1992;31:2865–82.10.1364/AO.31.002865Search in Google Scholar PubMed
8. Al-Saffar, D, Jihad, NJ. Design and implementation of optical switching network OSN. J Opt 2024. https://doi.org/10.1007/s12596-024-02148-7.Search in Google Scholar
9. Saidi, H, Hamdi, N. End-to-end performance of DF multihop hybrid RF/FSO system using MPPM coding and MIMO technique under dependent GG turbulence channels. Indonesian J. Electr. Eng. Comput. Sci. 2024;19:811–18. https://doi.org/10.11591/ijeecs.v19.i2.pp811-818.Search in Google Scholar
10. Hamoudi, ZA, Ali, MAA. Analysis of hybrid RF/FSO wireless communications links under foggy weather conditions. J Opt Commun 2023;45. https://doi.org/10.1515/joc-2023-0012.Search in Google Scholar
11. NJ Jihad, Layout design of optical OFDM screen-to-camera communications systems, J Opt 2023.10.1007/s12596-023-01566-3Search in Google Scholar
12. Jihad, NJ, Abbas, AH, Nourildean, SW, AbdAlmuhsan, MA. Convergence of multi-domain hybrid dispersion compensation paradigms for ultra-high-speed optical fiber transmission in spectrally-efficient coherent communication systems. Optik 2025. https://doi.org/10.1016/j.ijleo.2025.172509. [Online]. Available: https://www.sciencedirect.com/science/article/abs/pii/S0030402625002979.Search in Google Scholar
13. Jameel, ZN, Jihad, NJ. The imperfections of the screen to camera OCC systems. J Opt 2023;53:3743–8. https://doi.org/10.1007/s12596-023-01512-3.Search in Google Scholar
14. Ali, S. Performance evaluation of fixed modulation DWDM-MIMO FSO systems. IEEE Photon J 2022.Search in Google Scholar
15. Chen, Y. Hybrid RF/FSO link with fixed high-order modulation for urban wireless backhaul. Opt Commun 2021.Search in Google Scholar
© 2025 Walter de Gruyter GmbH, Berlin/Boston
