Consider an ideal lowpass filter with the cutoff frequency ωe = 0.3π. We want to approximate this filter using a frequency sampling design in which we choose 40 samples.
1. Choose the sample at ωc equal to 0.5, and use the naive design method to compute h(n). Determine the minimum stopband attenuation.
2. Now vary the sample at ωc, and determine the optimum value to obtain the largest minimum stopband attenuation.
3. Plot the magnitude responses in dB of the preceding two designs in one plot, and comment on the results.