MATLAB Implementation of FIR Filter with Signal Filtering Verification

This implementation involves writing MATLAB code to create FIR (Finite Impulse Response) filters. The process begins by designing the filter using appropriate MATLAB functions such as fir1 or firls for filter coefficient calculation. The magnitude-frequency characteristic curve is then plotted using freqz function to visualize the filter's frequency response. The implementation proceeds to filter three test signals: unit impulse function (generated using impz or dirac delta approximation), periodic square wave sequence (created with square function), and periodic triangular wave sequence (generated using sawtooth function with appropriate parameters). Each signal passes through the filter using the filter or conv function for convolution-based filtering. By comparing input and output signals through time-domain analysis and frequency spectrum examination (using fft), the filter's performance characteristics including attenuation, phase response, and frequency selectivity are validated to confirm effectiveness and accuracy. The code includes proper normalization, windowing techniques for filter design, and visualization of results using plot and stem functions for comprehensive analysis.