Intelligent microphone-an adaptive sound sensing system

An adaptive sound sensing system incorporating multiple microphones and a real-time digital signal-processing algorithm is described. The objective of this system is to receive a signal from a target sound source out of various noise environments with a better S/N ratio. The authors describe the hierarchical structure of the intelligent sensing system, comparing it with the human sensory system. Then they describe three approaches to intelligent sensors. The advantages and disadvantages of these three approaches are discussed. The adaptive sound sensing system is described as an example of one approach which is complicated for implementation, but flexible in performance. Many algorithms for adaptive filters are known, but these algorithms need knowledge of the target signal waveform or the transfer function between microphones and sound source for training. The authors propose new methods for filter adaptation without such knowledge