Patent ID: 7627129
Filing Date: 2009-12-01
Classification: H04R

Abstract:
1. An apparatus for suppressing feedback in an environment where a microphone and a loudspeaker are located, comprising: an embedder for embedding a test signal into a loudspeaker signal, a microphone signal or a modified microphone signal to obtain an embedding signal, wherein the microphone signal is output from the microphone and wherein the loudspeaker signal is input in the loudspeaker; wherein the embedder is formed to spectrally color the test signal by using a psychoacoustic masking threshold, so that the embedded signal is essentially inaudible; a processor for determining a characteristic of a transmission channel in the environment between the loudspeaker and the microphone by using the test signal and the microphone signal; a filter for filtering the loudspeaker signal or the embedding signal to obtain a filtered signal, wherein the filter is adaptable to be adapted to the characteristic of transmission channel with regard to its filter characteristic in response to the processor for determining; and a subtracter for subtracting the filtered signal from the microphone signal to obtain the modified microphone signal, in which a feedback is reduced.