Patent ID: 7127392

Claim:
A voice activity detector, comprising: a) an absolute value squarer, having an input for receiving a signal, and having an output; b) a low-pass filter, having an input connected to the output of said absolute value squarer, and having an output; c) a first function block for finding a mean value, having an input connected to the output of the low pass-filter, and having an output; d) a second function block for finding a maximum value, having an input connected to the output of the low-pass filter, and having an output; e) a threshold-crossing detector, including a first user-definable threshold, having an input connected to the output of the low pass filter, and having an output; f) a third function block for finding a number of points between a user-definable range, having a first input connected to the output of the low-pass filter, having a second input connected to the output of the first function block, having a third input connected to the output of the second function block, and having an output; g) a comparator, having an input connected to the output of the third function block, and including a second user-definable threshold to which to compare; h) a subtractor, having a first input connected to the output of the low pass filter, having a second input connected to the output of the second function block, and having an output; i) a padder, having an input connected to the output of the subtractor, and having an output; j) a Digital Fast Fourier Transformer, having an input connected to the output of the padder, and having an output; k) a normalizer, having an input connected to the output of the Digital Fast Fourier Transformer, and having an output; l) a classifier, having an input connected to the output of the normalizer, and having an output; and m) a decision-logic block, having a first input connected to the output of the threshold-crossing detector, having a second input connected to the output of the comparator, having a third input connected to the output of the classifier, and having an output.