Method and apparatus for generating a noise reduced audio signal using a microphone array

An apparatus for generating a noise reduced output signal from sound received by a first and second microphone arranged as microphone array, said apparatus comprises means for:

• transforming said sound received by said first microphone into a first input signal,
• wherein said first input signal is a frequency domain signal of an analog-to-digital converted audio signal corresponding to said sound received by said first microphone;
• transforming sound received by a second microphone into a second input signal,
• wherein said second input signal is a frequency domain signal of an analog-to-digital converted audio signal corresponding to the sound received by said second microphone;
• calculating, for each of the plurality of frequency components, a weighted sum of at least two intermediate signals that are calculated from the input signals by means of at least one complex valued transfer functions and at least one real valued Equalizer functions,
• said weighted sum having a weighing function with range between zero and one, with signal energy quotients of said intermediate functions as argument of said weighing function;
• and
• generating said noise reduced output signal based on said weighted sum of said first and said second intermediate function at each of said plurality of frequency components.

A computer program product comprising a physical computer readable storage medium containing computer executable program code for generating a noise reduced output signal from sound received by a first and second microphone arranged as microphone array, said computer executable code comprising:

• a code portion for transforming said sound received by said first microphone into a first input signal,
• wherein said first input signal is a frequency domain signal of an analog-to-digital converted audio signal corresponding to said sound received by said first microphone;
• a code portion for transforming sound received by a second microphone into a second input signal,
• wherein said second input signal is a frequency domain signal of an analog-to-digital converted audio signal corresponding to the sound received by said second microphone;
• a code portion for calculating, for each of the plurality of frequency components, a weighted sum of at least two intermediate signals that are calculated from the input signals by means of at least one complex valued transfer functions and at least one real valued Equalizer functions,
• said weighted sum having a weighing function with range between zero and one, with signal energy quotients of said intermediate functions as argument of said weighing function;
• and
• a code portion for generating said noise reduced output signal based on said weighted sum of said first and said second intermediate function at each of said plurality of frequency components.