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The open radio access network (O-RAN) architecture introduces RAN intelligent controllers (RICs) to facilitate the management and optimization of the disaggregated RAN. Reinforcement learning (RL) and its advanced form, deep RL (DRL), are increasingly employed for designing intelligent controllers, or xApps, to be deployed in the near-real time (near-RT) RIC. These models often encounter local optima, which raise concerns about their reliability for RAN intelligent control. We therefore introduce Federated O-RAN enabled Neuroevolution (NE)-enhanced DRL (F-ONRL) that deploys an NE-based optimizer xApp in parallel to the RAN controller xApps. This NE-DRL xApp framework enables effective exploration and exploitation in the near-RT RIC without disrupting RAN operations. We implement the NE xApp along with a DRL xApp and deploy them on Open AI Cellular (OAIC) platform and present numerical results that demonstrate the improved robustness of xApps while effectively balancing the additional computational load. 

In the rapidly evolving landscape of 5G technology, safeguarding Radio Frequency (RF) environments against sophisticated intrusions is paramount, especially in dynamic spectrum access and management. This paper presents an enhanced experimental model that integrates a self-attention mechanism with a Recurrent Neural Network (RNN)-based autoencoder for the detection of anomalous spectral activities in 5G networks at the waveform level. Our approach, grounded in time-series analysis, processes in-phase and quadrature (I/Q) samples to identify irregularities that could indicate potential jamming attacks. The model's architecture, augmented with a self-attention layer, extends the capabilities of RNN autoen-coders, enabling a more nuanced understanding of temporal dependencies and contextual relationships within the RF spectrum. Utilizing a simulated 5G Radio Access Network (RAN) test-bed constructed with srsRAN 5G and Software Defined Radios (SDRs), we generated a comprehensive stream of data that reflects real-world RF spectrum conditions and attack scenarios. The model is trained to reconstruct standard signal behavior, establishing a normative baseline against which deviations, indicative of security threats, are identified. The proposed architecture is designed to balance between detection precision and computational efficiency, so the LSTM network, enriched with self-attention, continues to optimize for minimal execution latency and power consumption. Conducted on a real-world SDR-based testbed, our results demonstrate the model's improved performance and accuracy in threat detection. 

The coexistence of active 5G communication signals and passive sensors in shared spectrum environments presents significant challenges due to radio frequency interference (RFI). This paper introduces a novel two-stage successive interference cancellation (SIC) architecture leveraging artificial intelligence (AI) to mitigate interference and preserve the integrity of passive sensing. The first stage employs a deep multilayer perceptron (D-MLP) trained with the Levenberg-Marquardt (LM) algorithm to reconstruct dominant active signals. The second stage, powered by a Bayesian Regularization (BR)-trained D-MLP, addresses residual non-linear and weak interference. Together, these stages achieve superior interference cancellation, ensuring robust separation of active and passive signals. The proposed architecture is evaluated in scenarios with varying interference complexities, including single and multiple active sources. Results demonstrate that the AI-assisted SIC framework significantly outperforms conventional methods, effectively reconstructing and removing 5G signals even under challenging conditions, such as low signal-to-noise ratios. The system also showcases adaptability, maintaining high performance when trained on one gain level and tested on another. This research advances the field by providing a scalable and robust solution for enabling reliable spectrum coexistence, particularly for Earth observation and environmental monitoring. 

The advent of 5G technology introduces significant advancements in speed, latency, and device connectivity, but also poses complex security challenges. Among typical denial-of-service (DoS) attacks, jamming attack can severely degrade network performance by interfering critical communication channels. To address this issue, we propose a novel security solution utilizing multipath communication, which distributes message segments across multiple paths to ensure message recovery even when some paths are compromised. This strategy enhances network resilience and aligns with zero-trust architecture principles. Moreover, the proposed scheme has been implemented in our testbed to validate the concept and assess the network performance under jamming attacks. Our findings demonstrate that this method eliminates the negative impacts caused by DoS attacks, maintaining the integrity and availability of critical network services. The results highlight the robustness of multipath communication in securing 5G networks against sophisticated attacks, thereby safeguarding essential communications in dynamic and potentially hostile environments. 

The Open Radio Access Network (O-RAN) architecture is reshaping telecommunications by promoting openness, flexibility, and intelligent closed-loop optimization. By decoupling hardware and software and enabling multi-vendor deployments, O-RAN reduces costs, enhances performance, and allows rapid adaptation to new technologies. A key innovation is intelligent network slicing, which partitions networks into isolated slices tailored for specific use cases or quality of service requirements. The RAN Intelligent Controller further optimizes resource allocation, ensuring efficient utilization and improved service quality for user equipment (UEs). However, the modular and dynamic nature of O-RAN expands the threat surface, necessitating advanced security measures to maintain network integrity, confidentiality, and availability. Intrusion detection systems have become essential for identifying and mitigating attacks. This research explores using large language models (LLMs) to generate security recommendations based on the temporal traffic patterns of connected UEs. The paper introduces an LLM-driven intrusion detection framework and demonstrates its efficacy through experimental deployments, comparing non-fine-tuned and fine-tuned models for task-specific accuracy. 

The open radio access network (O-RAN) represents a paradigm shift in RAN architecture, integrating intelligence into communication networks via xApps -- control applications for managing RAN resources. This integration facilitates the adoption of AI for network optimization and resource management. However, there is a notable gap in practical network performance analyzers capable of assessing the functionality and efficiency of xApps in near real-time within operational networks. Addressing this gap, this article introduces a comprehensive network performance analyzer, tailored for the near-real time RAN intelligent controller. We present the design, development, and application scenarios for this testing framework, including its components, software, and tools, providing an end-to-end solution for evaluating the performance of xApps in O-RAN environments.