Abstract: The most powerful digital filters are described and compared here. Here various windows are compared and demonstration of the best window is done, which is the one with minimum side lobes. This is hence the major objective of filtering operation. The experimental results show that the FIR filters designed in this paper are effective for filtering operation. Through this paper the intricacies of the window methods are explained in a simple and a subtle manner. In this paper, the design techniques of Low Pass filter using Rectangular Window, Bartlett window and Blackman-Harris of order 10 are presented. On the basis of their performances, it is shown that filter design by using Blackman–Harris window technique is better as it provides better result in terms of magnitude and phase response. The analysis of magnitude and phase response of proposed FIR Low Pass filter is performed using MATLAB simulation.

Keywords: DSP, Digital Filter, Low-Pass, FIR, Rectangular Window, Bartlett Window and Blackman-Harris Window.