Improving Robustness of Authentication System Based on Pinna Related Transfer Function

In this paper, we consider personal authentication technology using individual differences of acoustic transfer function measured from the pinna; the Pinna Related Transfer Function (PRTF). In addition, in this paper, considering the convenience in practical use, a smartphone that is not necessary to be worn on the pinna for each authentication is used to measure PRTF. However, it is known that in the case of using a smartphone, PRTF changes according to the emission direction of measurement signal toward the pinna, so the authentication rate is lower than that of using earphones and headphones. In this paper, we measure the PRTF from multiple locations and use them for learning at the same time. We demonstrate that the proposed authentication can correspond to the changes in the emission direction of each measurement and improve the robustness.