Cover
Vol. 16 No. 2 (2025)

Published: December 15, 2025

Pages: 213-224

Research Paper

Latency Budgeting of Dynamic Cloud Radio Access Network

Basim K. J. Al-Shammari 1
1Electrical Engineering Department, College of Engineering, University of Wasit, Al-Kut, Iraq
History
  • Received: October 19, 2025
  • Revised: December 5, 2025
  • Accepted: December 15, 2025
  • Available Online: December 15, 2025
DOI

https://doi.org/10.37649/AJES-25-036

Abstract

5G networks aim to improve capacity, reliability, and energy efficiency while reducing latency and increasing connection density. A vital goal is enabling real time communication, which demands extremely low latency, particularly within Dynamic Cloud Radio Access Network (DC-RAN) architectures designed for high coverage density. The FrontHaul (FH) link is a critical component for achieving this, as different FH technologies directly impact performance, latency and coverage in dense areas. This paper focuses on latency budgeting within a DC—RAN, analysing how FH technologies – millimetre wave (mmWave), optical fiber; and Free Space Optics (FSO) – affect overall End-to-End delay (E2E) and Round-Trip Time (RTT). By calculating the propagation and processing delays for various cell types, the analysis provides a comparative performance evaluation. The key finding is that, while processing delay dominates the total latency, the choice of FH link significantly influences performance and practicality. mmWave and FSO are suitable for short-range, dense deployments, whereas optical fiber offers stable, low latency over longer distances. Thus, the optimal FH selection depends on specific network objectives, including coverage, density, and weather conditions; toward meeting Ultra-Reliable Low-Latency Communication (URLLC) targets.

Keywords

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