Generalizable and Interpretable RF Fingerprinting with Shapelet-Enhanced Large Language Models

TL;DR

This paper introduces a novel RF fingerprinting framework combining 2D shapelets and pre-trained large language models to improve interpretability, generalization, and few-shot learning across diverse domains.

Contribution

The proposed method uniquely integrates variable-length 2D shapelets with pre-trained LLMs for interpretable and generalizable RF fingerprinting, supporting few-shot inference without retraining.

Findings

Achieves superior performance on six diverse datasets.

Demonstrates strong cross-domain generalization.

Supports effective few-shot inference.

Abstract

Deep neural networks (DNNs) have achieved remarkable success in radio frequency (RF) fingerprinting for wireless device authentication. However, their practical deployment faces two major limitations: domain shift, where models trained in one environment struggle to generalize to others, and the black-box nature of DNNs, which limits interpretability. To address these issues, we propose a novel framework that integrates a group of variable-length two-dimensional (2D) shapelets with a pre-trained large language model (LLM) to achieve efficient, interpretable, and generalizable RF fingerprinting. The 2D shapelets explicitly capture diverse local temporal patterns across the in-phase and quadrature (I/Q) components, providing compact and interpretable representations. Complementarily, the pre-trained LLM captures more long-range dependencies and global contextual information, enabling strong generalization with minimal training overhead. Moreover, our framework also supports prototype generation for few-shot inference, enhancing cross-domain performance without additional retraining. To evaluate the effectiveness of our proposed method, we conduct extensive experiments on six datasets across various protocols and domains. The results show that our method achieves superior standard and few-shot performance across both source and unseen domains.