Time Domain and Frequency Domain Analysis of Audio Signals Using MATLAB

In this article, I will provide a detailed explanation of how to perform time domain and frequency domain analysis of audio signals using MATLAB. First, we will utilize MATLAB's built-in functions to add Gaussian noise to audio signals, simulating real-world environmental conditions. Key implementation involves using the 'awgn' function or manually generating noise with 'randn' and adjusting signal-to-noise ratios. Next, we will explore signal filtering techniques using high-pass, low-pass, and band-pass filters to eliminate or emphasize signals within specific frequency ranges. The implementation typically involves designing filters using functions like 'designfilt' or 'butter', followed by applying them with 'filter' or 'filtfilt' for zero-phase filtering. We'll discuss parameters like cutoff frequencies, filter order, and their impact on signal integrity. Finally, we will demonstrate how to display waveform diagrams of filtered audio signals using MATLAB's plotting functions such as 'plot' for time-domain visualization and 'spectrogram' or 'pwelch' for frequency-domain analysis. These visualizations help in better understanding filter effects and signal characteristics. Through this tutorial, you will learn fundamental MATLAB techniques for audio signal processing and analysis, providing a solid foundation for research and applications in the field of audio signal processing. The article includes practical code snippets and explanations of core algorithms to ensure comprehensive understanding.