Voice Command II: A DSP Implementation of Robust Speech Recognition in Real-World Noisy Environments

The \Voice Command" system, designed for isolated word recognition tasks in real-world noisy environments, was implemented on a xed-point DSP board to operate in real-time. Simple auditory model, i.e., zero-crossings with peak amplitudes (ZCPA) model, is used for noise-robust feature extraction , and neural network classiier recognizes input patterns. The system performance is further improved by incorporating speaker adaptation and out-of-vocabulary word rejection capabilities. The radial basis function (RBF) classiier provides better rejection performance than multi-layer perceptron (MLP) classiiers.