Coherence based reflection coefficient estimation

Kurzfassung

A new method to measure the reflection coefficient of surfaces is presented. It only relies on a single noise source and a single microphone. The method is robust to inaccuracies in the experimental setup and does not require high end measurement equipment. It is derived from the blind source separation problem where the direct and reflected sound are reconstructed from their mixed signal. To do so, an analytical solution to the mixing matrix is presented. It is based on a short window Welch coherence estimation of the measured signal and a by the reflection time shifted version of the signal. The method is validated with simulated and real experimental data.