[SOLVED] Ece-210-b homework #6 filters

This homework is… filter. All filter. You’ll feel like a barnacle afterwards.
Especially since you’ll need to derive sustenance from the water around you:
this homework does not have notes, so you’ll have to go to the Mathworks docs
yourself! I’ll provide some links to documentation pages, and will make myself
available as a resource, but this is an exercise in learning on your own. Good
luck, and let me know if you have questions!

The following table contains a few filter specifications:
Class Type Rpass Rstop fpass fstop
Butterworth bandpass 1 dB 50 dB fs/6, fs/3 fs/7, fs/2.5
Elliptic bandstop 1 dB 50 dB fs/7, fs/2.5 fs/6, fs/3
Chebyshev Type I lowpass 5 dB 40 dB fs/9 fs/8
Chebyshev Type II highpass 5 dB 40 dB fs/3 fs/4
Your task is to design them.

Assume fs
is 44.1 kHz. For each filter, do the
following:
1. Either
(a) use filterDesigner to generate a function that creates the given
filter, then call that function, or

(b) use fdesign and its associated functions to set filter specifications,
create a filter object, and apply the filter.
Use each of these strategies at least once. Since filterDesigner generates functions that use fdesign internally, it’s a useful tool to learn the
syntax.

2. Acquire a frequency response plot (both magnitude and phase) using
fvtool.

3. Apply the filter to 2 seconds of Gaussian white noise (samples from a
normal distribution, assumed to be sampled at fs).

4. Plot the Fourier transform of the filtered signal (using fft). It should
look a lot like the filter response, as white noise has a uniform frequency
spectrum. Refer to the notes for proper scaling and use of fft.

5. Play back the unfiltered and filtered signals using soundsc and give your
impressions: what, qualitatively, was the change the filter made?