Lab 12

1. Consider the filter with the transfer function 1 + 0.4 z^{-2} + 0.2z^{-5}. What are its roots? (You’re welcome to use an online tool to find out.) Which root is closest to the unit circle?

2. Design a filter that completely cancels tones at 4500 and 7803 Hz. Show that it works by filtering the sequence of tones at 3500, 4500, 7503, and 7803 (so the second and fourth ones disappear).