Patent ID: 8379876
Filing Date: 2013-02-19
Classification: H04R

Abstract:
1. An audio device, comprising: a microphone array for receiving ambient audio signals, comprising at least a first microphone and a second microphone, wherein the first and second microphones respectively generate a first audio signal and a second audio signal from the ambient signals; an error detector, coupled to the first and second microphones, detecting functions of the first and second microphones based on the first and second audio signals to generate a status signal; a digital signal processor (DSP), coupled to the first microphone, second microphone and the error detector, processing the first and second audio signals based on the status signal, wherein, if the status signal indicates that both the first microphone and the second microphone are normal, the DSP switches to a normal mode in which both the first and second audio signals are processed, and if the status signal indicates that only the first microphone or the second microphone is defective, the DSP switches to a single microphone mode in which only audio signals from the remaining normal microphone is processed, and if the status signal indicates that both the first and second microphones are defective, the DSP generates an error indication signal and stops processing the first and second audio signals; wherein the error detector comprises: a first activity detector, comparing the first audio signal with a local activity threshold to generate a first activity flag for indicating voice activity of the first audio signal; a second activity detector, comparing the second audio signal with the local activity threshold to generate a second activity flag for indicating voice activity of the second audio signal; a power difference detector, comparing the first and second audio signals to generate a power difference flag for indicating whether the differences between the first and second audio signals exceed a predetermined ratio; and a correlation detector, determining correlation of the first and second audio signals to generate a correlation flag for indicating whether the first and second audio signals are correlated.