A Channel Robust Radio Frequency Fingerprint Authentication Method Based on Hadamard Product Comparison.

Radio Frequency Fingerprinting (RFF) is an emerging identification technology that utilizes wireless signals to identify specific devices. Due to the presence of variable channel conditions in practical applications, designing channel-robust RFF techniques is a challenging task. This paper proposes a channel-robust RFF authentication method, which implements the authentication function by comparing the Hadamard product results of two different fixed signal segments. In order to further mitigate the impact of variable channel conditions on authentication results, a windowed Channel Impulse Response (CIR) compensation method is also utilized in this paper. Taking the IEEE 802.11 system as an example, the experiment uses 4 Wi-Fi routers of the same model and production batch in three different scenarios: indoor static, indoor mobile, and outdoor corridors. Using the original data comparison method, the average accuracy rate exceeds 95%, and it can be further improved by 1% to 2% after the windowed CIR compensation. Moreover, using only one frame as reference data, this approach can also achieve approximately 95% authentication accuracy.