Digital Butterworth Filter Design

                  In this experiment, digital Butterworth low pass and high pass filters have been designed using Scilab software. Scilab is a free and open source software for numerical computation where one can use the source code and modify it according to the requirement of the project or research for personal or commercial use. We implemented low pass and high pass filter where we had to enter the pass band and stop band attenuation, pass band and stop band digital frequencies and the sampling frequency. Ideally the observed stop band attenuation should be greater than the calculated while the pass band attenuation should be lesser than the calculated one. However it was seen that if the difference in the pass band and stop band frequencies was less, then the above values were not close to the calculated ones. Hence we increased the gap between the two frequencies which got us the accurate results.