Modeling of Pinna Related Transfer Functions (PRTF) using Finite Element Method (FEM)

Pinna Related Transfer Functions (PRTFs) are signal processing models that represent the modifications undergone by the acoustic signal as it interacts with the listener’s pinna (outer ear). PRTFs are used to generate binaural sounds, especially those coming from an elevation. The complex shape of the pinna causes reflections, diffractions and resonances that give rise to a unique PRTF for each individual. One can measure individual PRTFs using specialized recording systems; however, these systems are prohibitively expensive and restrict the portability of the 3-D sound system. This paper provides an alternative to real PRTF measurement, where the 3-D images of artificial human ears are used to generate the PRTFs using COMSOL – which is a simpler, efficient, accurate and cost effective way. The synthesized PRTFs are compared with the real PRTFs measured at Florida International University’s DSP lab. The comparison shows a percentage match and a cross correlation higher than 80%.