Innocent Nhlanhla Makhubela

The operation of 5G New Radio in unlicensed bands (NR-U) is a critical enabler for expanding wireless capacity. However, ensuring fair coexistence with incumbent Wi-Fi systems remains a significant implementation challenge. While numerous simulation studies have explored this topic, there is a lack of experimental validation using accessible, opensource hardware platforms. In this paper, we present a practical evaluation of NR-U and Wi-Fi coexistence using a SoftwareDefined Radio (SDR) testbed. We implement a standalone NRU gNodeB on the OpenAirInterface platform, incorporating Listen-Before-Talk (LBT) mechanisms to govern channel access. Preliminary discrete-event simulations were utilized strictly for parameter selection to ensure regulatory compliance before hardware deployment. The primary contribution of this work is the experimental verification of NR-U/Wi-Fi coexistence using an open-source SDR platform under real interference conditions. Experimental results demonstrate that properly configured NRU can coexist with Wi-Fi in the 5 GHz band, maintaining stable incumbent throughput and achieving a high fairness index (> 0.95). These findings provide empirical evidence supporting the feasibility of NR-U deployments using open-source SDR tools.