Cepstral Deconvolution Method for Measurement of Absorption and Scattering Coefficients of Materials

A method based on cepstral deconvolution technique is proposed for measurement of absorption and scattering coefficients of materials. The reverberation room method standardized by International Organization for Standardization (ISO) is taken as the reference for measurements. Several measurements are conducted in a physically scaled reverberation room and results are evaluated by these two methods. Two methods show slight differences in the estimation of specular parts of room impulse responses essential for determination of scattering coefficients. In the standard method, the specular part is found by synchronous averaging of impulse responses. However, the cepstral deconvolution method utilizes cepstral analysis to obtain the specular part instead of averaging. Results obtained by these two approaches are compared for different test materials. Both methods have yielded almost the same values for absorption coefficients. On the other hand, lower scattering coefficient values have been obtained for the cepstral deconvolution method.