the experiments on Filters, required us to find output of a digital Butterworth filter. The Butterworth filter was designed using Transfer Domain Method - Bilinear Transformation (BLT). User was prompted to input values like Attenuation in Stop band (As) and Pass band (Ap) as well as Pass band frequency, Stop band frequency and sampling frequency. Subsequently, Order of filter, cut off frequency, normalised LPF and denormalised filter were calculated. Transfer function was computed and the filter was obtained. Both LPF and HPF were calculated and their magnitude response was observed. It was observed that magnitude response is maximally flat in both stop band and pass band.
THE CODE CAN BE FOUND AT https://docs.google.com/document/d/15QM0rGZNQAsTLD9hyonYlxq9tboYebGRvwTNzNeXQwk/edit
THE CODE CAN BE FOUND AT https://docs.google.com/document/d/15QM0rGZNQAsTLD9hyonYlxq9tboYebGRvwTNzNeXQwk/edit
Thanks for sharing your experience on this experiment!
ReplyDeletethe 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.
ReplyDeleteDue to its maximum flat pass band nature it is used as anti-aliasing filter in data converter applications,digital filters for motion analysis,high quality audio applications.
ReplyDelete