International Research Journal of Innovations in Engineering and Technology - IRJIET International Open Access, Monthly, Peer Reviewed, Reputed Journal ISSN (online): 2581-3048

Impact Factor (2025): 6.9

DOI Prefix: 10.47001/IRJIET

Adaptive Uplink-Downlink Resource Partitioning for CLI Mitigation in 5G HetNets with Dynamic-TDD

Praise Igochi OnuDepartment of Electrical/Electronic Engineering, University of Port Harcourt, NigeriaBourdillon O. OmijehDepartment of Electrical/Electronic Engineering, University of Port Harcourt, Nigeria

Vol 9 No 8 (2025): Volume 9, Issue 8, August 2025 | Pages: 96-106

International Research Journal of Innovations in Engineering and Technology

OPEN ACCESS | Research Article | Published Date: 05-09-2025

doi Logo doi.org/10.47001/IRJIET/2025.908013

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Abstract

Advanced duplexing techniques are now required to ensure effective use of spectrum resources in 5G and beyond networks due to the exponential growth in mobile traffic and device connectivity. Unlike static-TDD, which uses fixed configurations, dynamic-TDD allows for flexibility in adjusting UL and DL sub-frame allocations to real-time traffic demands. But cross-link interference (CLI), especially DL-to-UL interference from high-power base station transmissions, poses a serious limitation to D-TDD systems. The improved interference mitigation framework presented in this paper suppresses CLI while optimizing coverage probability by combining adaptive 3D beamforming, fractional power control (FPC), and a multi-tier heterogeneous network model. The interference-to-signal ratio (ISR), path-loss propagation, and SINR coverage probability were analytically formulated and assessed under various FPC values (k = 0–1) and path loss exponents (2b = 2.5, 3.5). Based on simulation results, the suggested model significantly outperforms the traditional system, improving the DL coverage probability by up to 30% and the UL coverage probability by more than 53%. With considerable benefits for cell-edge users, the results show that uplink interference mitigation is more successful because user equipment has a lower transmit power than base stations. These results demonstrate the effectiveness of real-time interference-aware resource allocation and adaptive beamforming as scalable approaches for upcoming ultra-dense D-TDD deployments.

Keywords

cross-link interference, dynamic-TDD, 3D beamforming, HetNet, static-TDD


Citation of this Article

Praise Igochi Onu, & Bourdillon O. Omijeh. (2025). Adaptive Uplink-Downlink Resource Partitioning for CLI Mitigation in 5G HetNets with Dynamic-TDD. International Research Journal of Innovations in Engineering and Technology - IRJIET, 9(8), 96-106. Article DOI https://doi.org/10.47001/IRJIET/2025.908013

Licence Copyright (c) 2026 International Research Journal of Innovations in Engineering and Technology creative common licence This work is licensed under Creative common Attribution Non Commercial 4.0 Internation Licence
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