A word speech recognition apparatus recognizes a speech inputted to a microphone (11). A feature extracting portion (20) extracts a feature parameter based on a aural signal waveform outputted from the microphone. The feature extracting circuit comprises a pitch cycle extraction circuit (21) for extracting pitch frequency of the speech signal waveform, a digital filter (23) for extracting, as a feature parameter, spectrum data of the speech signal waveform, and a filter coefficient setting circuit (22) for setting a filter coefficient so that a resonance frequency of the digital filter is an integral multiple of the pitch frequency. The feature parameter extracted from the feature extracting circuit is stored in an input pattern memory (3). A recognition processing portion (50) evaluates similarity between the feature parameter stored in advance in a registration pattern memory (4) and the feature parameter stored in the input pattern memory, so that speech recognition processing is made. Improved signal in noise performance results from very narrow bandwidth filters.
Speech recognition apparatus