In this experiment, students become familiar with speech signals, their statistical properties and with a model that represents the production of such a signal. Speech coders based on similar models are used in many systems, such as mobile telephony and voice-over-IP.
In this experiment, an voice encoder-decoder system is built and analyzed in MATLAB. The blocks that make up such systems are VAD (Voice Activity Detector), a voiced/unvoiced classifier, a pitch (the basic frequency of speech) detector and a parametric model of the spectral envelope of the speech signal. At the end of the experiment, students record their voice to evaluate the quality of the encoder-encoder system they have built.