吸收边界条件下雪人模型近场头相关传输函数

Near-field Head-related Transfer Functions of Snowman Model Under Absorption Boundary Conditions

采用扩散场人体平均吸声量导出人体表面法向声吸收系数,给出雪人模型球形头部和躯干的吸收边界,计算得到近场头相关传输函数(HRTF)。结果表明,在表面吸声条件下,HRTF的平均幅值和波动幅度较刚性条件时略有减少,但差别基本在1.0dB以内,因而采用通常的刚性表面边界条件进行计算不会带来大的误差。另一方面,增大球形躯干表面的吸声系数会使躯干与头部间多重散射的作用减少,从而HRTF幅度的波动减少,对应头相关脉冲响应(HRIR)的二次脉冲幅度也减小。

Based on the normal sound absorption coefficients deduced from the average absorption of human body in reverberation room, the absorption boundary conditions of snowman model are proposed and applied to calculate the near-field HRTFs （Head-Related Transfer Functions）. The results show that, under the absorption boundary conditions, the average magnitude and fluctuations of HRTFs are smaller than the ones under the rigid boundary conditions, however, the difference is basically within 1.0 dB. Therefore, applying rigid boundary conditions to calculate HRTFs only results in insignificant errors. On the other hand, with the absorption coefficients of the spherical torso increasing, the effects of the multiple scattering between the spherical torso and head become weaker, so that the fluctuations of the HRTFs decrease. Correspondingly, the second peak in the HRIRs（Head- Related Impulse Responses） decrease.