In this study, it is possible to determine the acoustic properties by using the fast Fourier transform when an acoustic source is driven by white noise. Because the process is stationary and ergodic, the cross spectral density between two microphone locations is decomposed into the cross spectral densities between the speaker source and each microphone location. Thus the cross spectral density does not have to be determined simultaneously. It is possible to measure the acoustic transfer function evaluated from the pressure to pressure at two microphone locations sequentially using a single microphone.
In this paper the complex reflection coefficients and absorption coefficients are evaluated by the transfer functions obtained by the FFT analyzer, and their results are compared with those of the conventional Standing-Wave-Ratio method. This new method saves a lot of time and labor.
