IIR and FIR Filters Exercises  

1. Choose an FIR low-pass filter of order 10 with cut-off frequency at 0.35. Select the speech signal with the HF (high frequency) component. Listen to the sound before and after filtering. If the speech signal was sampled at 8192 Hz, what would the cutoff frequency of the filter correspond to in Hz?
   
   
2. Now choose an IIR high-pass filter of same order 10 with cut-off frequency at 0.55. Apply the same speech signal as above to the filter and listen to both sounds, before and after filtering. What do you observe?
   
   
3. Comment on the pole-zero diagram of the IIR filter designed in the above item and observe how the distribution of zeros and poles are in harmony with the frequency response of the filter.
   
   
4.  Choose the speech signal that is contaminated by a tone at 2000Hz. Design two stop-band IIR filters of orders 3 and 10, with cutoff frequencies at 0.4 and 0.5. Observe the pole-zero diagram of both filters. Listen also to the sounds before and after filtering in both cases. 
   
   
5. Choose the speech signal that is contaminated by a tone at 1357 Hz. Design a stop-band FIR filter that eliminates the tone.
   
   
6. Filter an FM signal with a high-pass IIR filter with cut-off frequency at 0.6. Listen to the signal before and after filtering. Now repeat with a low-pass IIR filter with cut-off frequency at 0.2.