The formula to calculate the transfer function H(z) is:
\[ H(z) = \frac{1 - 2r\cos(\omega₀) + r^2}{1 - 2\cos(\omega₀) + 1} \]
Where:
Let's say the radius (\( r \)) is 0.9 and the angular frequency (\( \omega₀ \)) is 1 radian. Using the formula:
\[ H(z) = \frac{1 - 2 \times 0.9 \times \cos(1) + 0.9^2}{1 - 2 \times \cos(1) + 1} \]
We get:
\[ H(z) = \frac{1 - 1.8 \times 0.5403 + 0.81}{1 - 2 \times 0.5403 + 1} \approx 0.91 \]
So, the transfer function \( H(z) \) is approximately 0.91.
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