Design of Butterworth Filter

  A filter is a very important part of the system, so the task was to design the Butterworth filter.This experiment was performed using Scilab which is the open source alternative to MATLAB.We have designed both filters i.e.High Pass Filter and Low Pass Filter using Scilab.
Here the parameters like passband attenuation (Ap), stopband attenuation (As), analog passband frequency (Fp), analog stopband frequency (fs) and sampling frequency (Fs).were taken as inputs. Sampling frequency selected almost 4 times higher than the highest frequency parameter, for LPF Fp<Fs<fc and for HPF Fs<Fp<Fc  Based on these parameters, a digital Butterworth filter (LPF and HPF) was designed using Bi-Linear Transformation(BLT) Method. Once, the digital filter was designed, order and transfer function were displayed and magnitude response of the filter was shown in the Scilab Graphic window.

Comments

  1. Unknown26 April 2017 at 07:58

    greatest advantage of this filter is its maximally flat pass band

    ReplyDelete
  2. Amol28 April 2017 at 02:35

    There are no ripples in the pass band and stop band of Butterworth filter.

    ReplyDelete
  3. Unknown28 April 2017 at 02:52

    Butterworth filter is usefull in applications where transition band is not concerned

    ReplyDelete
    Replies
    1. Unknown3 May 2017 at 12:04

      And if transition is concerned Chebyshev filter is used

      Delete
  4. Unknown28 April 2017 at 04:59

    Maximally flat filter is also a Butterworth filter

    ReplyDelete
  5. Aniket kharche28 April 2017 at 09:48

    less memory required for storage of coefficients in butterworth digital filter

    ReplyDelete

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