Efficiency evaluation and orthogonal basis determination in functional HRTF modeling

This paper consider the problem of how to evaluate the efficiency of a 3D continuous functional HRTF model in rep resenting measured data. The proposed method is based on Karhunen-Loeve theorem. After investigating the optimization problem of representing the process with an finite linear combination of orthogonal functions in L space by means of the least squared method, the variance of random variables involved in the model is found the key metric in efficiency evaluation of a given functional model. Then, the coefficients of the 3D continuous HRTF model are analyzed. The results show that the efficiency of the model in spatial component expansion is around 70% and the best choice in frequency component expansion is the spherical Bessel function.