Spectrum analysis of speech signal based on SPTool

This paper utilizes the powerful capability of Matlab and its graphical user guide to design rational digital filters, realizes spectral analysis of the speech signal with noise. First of all, a speech was recorded, and some noises were added to the original speech signal; then several common digital filters were used to filter the speech signal, playing the sound before and after filtering; then we compared and analyzed the results. Eventully, this paper realized spectrum analysis of the speech signal with noise, and realized the purpose of filtering noise.