Physical Layer Deception based on Semantic Distortion

Physical layer deception (PLD) is a framework we previously introduced that integrates physical layer security (PLS) with deception techniques, enabling proactive countermeasures against eavesdropping rather than relying solely on passive defense. We extend this framework to a semantic communication model and conduct a theoretical analysis using semantic distortion as the performance metric. In this work, we further investigate the receiver's selection of decryption strategies and the transmitter's optimization of encryption strategies. By anticipating the decryption strategy likely to be employed by the legitimate receiver and eavesdropper, the transmitter can optimize resource allocation and encryption parameters, thereby maximizing the semantic distortion at the eavesdropper while maintaining a low level of semantic distortion for the legitimate receiver. We present a rigorous analysis of the resulting optimization problem, propose an efficient optimization algorithm, and derive closed-form optimal solutions for multiple scenarios. Finally, we corroborate the theoretical findings with numerical simulations, which also confirm the practicality of the proposed algorithm.