Identifying noise source strength is difficult when tests are conducted in a reverberant environment. In the problem shown to the right a noise source emits a signal that arrives on a receiver via two paths. The reflection, R, is a delayed and scaled replica of the direct signal, S, arriving from a different direction. Tests conducted with and without the reflecting surface reveal that the combined signal, Y, is composed from a convolution of the direct and reflected signals and can be several dB higher than the direct signal alone. In our work we deconvolve the signal using the CEPSTRUM to identify the delay time. Using multiple microphones we can separate several signals using array processing into the arrival direction, and the delay time.
Additional noise from reflection
echo delay te = .0038 sec
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