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Research Article |

Energy-Efficient Sub-Millisecond DWDM Backhaul for 6G Open RAN

Author(s): Ali Abduljabbar Abdulsattar1, Hussein Shakor Mogheer2, Mohammad S. Al-Abadi3, and Yassir AL-Karawi4*

Published In : International Journal of Electrical and Electronics Research (IJEER)        Volume 13, Issue 4

Publisher : FOREX Publication

Published : 25 December 2025

e-ISSN : 2347-470X

Page(s) : 861-869

DOI: https://doi.org/10.37391/IJEER.130426

Abstract

Wavelength-aware and constraint-driven framework is presented for dense WDM optical backhaul in 6G Open RAN. The design jointly minimizes energy while enforcing explicit sub-millisecond delay bounds under non-stationary traffic and integrates cleanly with near-RT RIC control. A three-stage controller computes a feasible allocation through projected primal–dual updates then perform energy-aware wavelength pruning and finally executes latency-responsive reconfiguration on incipient violations. Evaluation across diverse topologies and bursty as well as diurnal loads shows up to 32% lower optical power than static provisioning with delays concentrated in 0.7–0.8ms and low control overhead. Comparative experiments against greedy heuristics and a lightweight actor–critic baseline indicate superior energy–latency trade-offs and fewer violations above one millisecond. A complexity analysis shows per-interval updates scale as O(|E||W|) and fit within near-real-time control cycles which supports practical deployment feasibility on commodity RIC servers. The approach operationalizes elastic optical networking as a first-class dimension for ORAN backhaul and offers a deployable path to greener and delay-bounded transport for 6G services.

Keywords: 6G Optical Backhaul, DWDM, O-RAN, Lagrangian Optimization, Energy–Latency Optimization, near-RT RIC.




Ali Abduljabbar Abdulsattar, Assistant Lecturer, Department of Communications Engineering, College of Engineering, University of Diyala, Baqubah, Iraq

Hussein Shakor Mogheer, Lecturer, Department of Communications Engineering, College of Engineering, University of Diyala, Baqubah, Iraq

Mohammad S. Al-Abadi, Lecturer, Department of Communications Engineering, College of Engineering, University of Diyala, Baqubah, Iraq

Yassir AL-Karawi*, Assistant Professor, Department of Communications Engineering, College of Engineering, University of Diyala, Baqubah, Iraq; Email: yassir_al-karawi_eng@uodiyala.edu.iq

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Ali Abduljabbar Abdulsattar, Hussein Shakor Mogheer, Mohammad S. Al-Abadi, Yassir AL-Karawi (2025), Energy-Efficient Sub-Millisecond DWDM Backhaul for 6G Open RAN. IJEER 13(4), 861-869. DOI: 10.37391/IJEER.130426.