Help in solving these problems
1. Design a butterworth analogue low pass filter to satisfy ωp(cut-off frequency)=0.3π rad/s for n=3,7 and 10. Plot the poles-zero graph for the frequency response.

2. Calculate the minimum order of a normalised butterworth low pass filter to have and attenuation αs = 16dB at a frequency ωs=0.3π rad/s
(All using matlab codes)

Question

Help in solving these problems
1. Design a butterworth analogue low pass filter to satisfy ωp(cut-off frequency)=0.3π rad/s for n=3,7 and 10. Plot the poles-zero graph for the frequency response.

2. Calculate the minimum order of a normalised butterworth low pass filter to have and attenuation αs = 16dB at a frequency  ωs=0.3π rad/s
(All using matlab codes)

anonymous · Answer

If you have the Signal Processing Toolbox, you can use the functions "butter" to design the filter (it can be implemented with "filter" or with no phase-shift with "filtfilt"). The poles can be plotted using the "zplane" function. 

You can use "phasez" to help you design the butterworth filter to meet your requirements. Additionally, there is a filter design GUI you can use. Type "fdatool" into the command window.

anonymous · Answer

thank you very much. quite helpful

anonymous · Answer

This is more than quite helpful. it's goood. I will explore more into the gui tool and see more solutions. Thanks