Quiz Chapter 11.04: Discreet Fourier Transform MULTIPLE CHOICE TEST (All Tests) DISCREET FOURIER TRANSFORM (More on Discrete Fourier Transform) FAST FOURIER TRANSFORMS (More on Fast Fourier Transforms) Pick the most appropriate answer 1. Given that W=e^{-i(2 \pi / N)}, where N=3. Then F=W^{N} can be computed as F= 0 1 -1 e 2. Given that W=e^{-i(2 \pi / N)}, where N=3. Then F=W^{N/2} can be computed as F= 0 1 -1 e 3. Given that N=2, \{ f \} = \begin{Bmatrix}4-6i\\-2+4i\end{Bmatrix}. The values for vector \{\widetilde{C}^{R}\} shown in \widetilde{C}_{n}^{R}=\displaystyle\sum_{k=0}^{N-1}\{f^{R}(k) \cos (\theta)+f^{I}(k) \sin (\theta)\} can be computed as: \begin{Bmatrix}-2\\-6\end{Bmatrix} \begin{Bmatrix}-2\\6\end{Bmatrix} \begin{Bmatrix}2\\-6\end{Bmatrix} \begin{Bmatrix}2\\6\end{Bmatrix} 4. Given that N=2, \{ f \} = \begin{Bmatrix}4-6i\\-2+4i\end{Bmatrix}. The values for \{\widetilde{C}^{I}\} shown in Equation (22D) \widetilde{C}_{n}^{I}=\displaystyle\sum_{k=0}^{N-1}\{f^{I}(k) \cos (\theta)-f^{R}(k) \sin (\theta)\} can be computed as: \begin{Bmatrix}-2\\-10\end{Bmatrix} \begin{Bmatrix}-1\\-10\end{Bmatrix} \begin{Bmatrix}-2\\-5\end{Bmatrix} \begin{Bmatrix}-1\\-5\end{Bmatrix} 5. The forcing function F(t) is given as: F(t) = \displaystyle\sum_{n=0}^{7} 10 \sin (2 \pi n t) To avoid the aliasing phenomenon, the minimum number of sample data point N_{min} should be 8 16 24 32 6. Based on the figure below aliasing phenomena will not occur because there were 2 sample data points per cycle. 4 sample data points per cycle. 4 sample data points per 2 cycles. 6 sample data points per 2 cycles. Loading …