One-Class Classification as GLRT for Jamming Detection in Private 5G Networks
Matteo Varotto, Stefan Valentin, Francesco Ardizzon, Samuele Marzotto, Stefano Tomasin
TL;DR
This work addresses jamming detection in private 5G networks by framing watchdog IQ monitoring as a one-class problem and approximating the GLRT with a CNN trained on legitimate data and synthetically generated attack samples. The detector combines a two-class CNN with a uniformly distributed artificial dataset $\mathcal{D}^*_1$ to emulate jammer statistics, supported by theoretical grounding that links this training to GLRT performance. Across multiple jamming scenarios and time-window sizes, the CNN with synthetic data significantly outperforms a convolutional autoencoder baseline, achieving larger separation between false-alarm and misdetection curves and demonstrating practical gains for physical-layer security in industrial private networks. The results suggest a robust, attacker-independent approach for wireless intrusion prevention systems in private 5G deployments, with potential for broader adoption in secure communications.
Abstract
5G mobile networks are vulnerable to jamming attacks that may jeopardize valuable applications such as industry automation. In this paper, we propose to analyze radio signals with a dedicated device to detect jamming attacks. We pursue a learning approach, with the detector being a CNN implementing a GLRT. To this end, the CNN is trained as a two-class classifier using two datasets: one of real legitimate signals and another generated artificially so that the resulting classifier implements the GLRT. The artificial dataset is generated mimicking different types of jamming signals. We evaluate the performance of this detector using experimental data obtained from a private 5G network and several jamming signals, showing the technique's effectiveness in detecting the attacks.
