Adaptive Filtering of Speech Signals
Original Publication Date: 1986-Nov-01
Included in the Prior Art Database: 2005-Mar-09
A method is described for automatically controlling an adaptive filter bank used for speech processing. The use of adaptive filters allows the spectral characteristics of the incoming speech signal to be estimated using fewer filters than would be required with a stationary filter bank system. Referring to Fig. 1, in the prior art, the incoming speech signal 10 would be processed by a filter bank consisting of a number of stationary bandpass filters 20. The output of each of the filters 20 is processed by an energy detector 30, providing a fixed bank spectral estimate. The disadvantage of this approach is that many filters are required to capture the spectral characteristics accurately enough for applications such as speech recognition.