This was our first expirience working with scilab so it took quite sometime to get used to it. We were aware the inbuilt function buttmag() which made our work easier. According to the input specifications of attenuation(pass band and stop band) and passband and stopband frequencies, we plotted the magnitude and pole zero plot of low pass and high pass butterworth filter.
We learned that the butterworth filter is monotonic in it's pass band as well as stop band i.e. it does not have any ripples.Also how steep the transition band is depends on the order of the filter.
Inspite of help from google, we took a considerable amount of time to finish this experiment. Working during sdp sessions was also not fruitful. It took us 3 weeks to get through this one.
Inspite of help from google, we took a considerable amount of time to finish this experiment. Working during sdp sessions was also not fruitful. It took us 3 weeks to get through this one.
Codes at : https://drive.google.com/open?id=0Bzfvoo_rjoa8S19TN2V1SE9kckk
scilab codes ticks can also be obtained from scilabninja.com
ReplyDeleteAnalog Butterworth LPF has only poles and no zeros.
ReplyDeleteThis is because the transfer function of Butterworth filter is of the form: H(s)= 1/(f(s))
Deletehence it always deal with the poles and not zeros
Due to its maximum flat pass band nature it is used as anti-aliasing filter in data converter applications.
ReplyDeleteChebyshev filters have sharper frequency cut-off while butterworth filters have a wide transition band
ReplyDeleteCompared with a Chebyshev Type I/Type II filter, the Butterworth filter has a slower roll-off, and thus will require a higher order to implement a particular stopband specification, but Butterworth filters have a more linear phase response in the pass-band than Chebyshev Type I/Type II filters can achieve.
ReplyDeletebutterworth filter has better magnitude response compared chebyshev
ReplyDeletedetailed explaination
ReplyDelete