PUF-Based Reconfigurable QAM Modulation for Secure Communication

Cyberattacks pose persistent threats to wireless communication, especially in low-power IoT devices where conventional cryptography is impractical. This work leverages Physical Unclonable Functions (PUFs) to deterministically configure a session-specific modulation profile. For each session, the PUF response to a challenge dynamically determines both the modulation order, and also permuting the bit-to-symbol mapping to create a unique, obfuscated QAM constellation. This ensures that each communication instance is uniquely encoded and obfuscated at the physical layer. The receiver uses the same challenge-response pair to infer the session specific mapping and to demodulate the signal. This dynamic constellation generation thwarts adversaries by preventing pattern reuse and rendering modulation recognition by machine learning models ineffective. Importantly, the session-specific and device-dependent nature of the scheme ensures that even if a node is compromised, other nodes remain secure. The approach operates entirely at the signal level and introduces minimal computational burden for IoT and embedded communication platforms.