DSP QUIZ DIF FFT

The radix-2 DIF FFT algorithm requires that the input sequence length be a power of:

• 1. 2
• 2. 3
• 3. 4
• 4. Any positive integer

The DIF FFT algorithm computes the DFT in:

• 1. Natural order
• 2. Bit-reversed order
• 3. Both natural and bit-reversed orders
• 4. None of the above

In the radix-2 DIF FFT algorithm, each stage consists of:

• 1. N/2 complex multiplications and N/2 complex additions
• 2. N/2 complex multiplications and N/4 complex additions
• 3. N/4 complex multiplications and N/2 complex additions
• 4. N/4 complex multiplications and N/4 complex additions

In the radix-2 DIF FFT algorithm, the butterfly structure is used to:

• 1. Combine two input sequences of length N/2 into one output sequence of length N
• 2. Split the input sequence of length N into two sequences of length N/2
• 3. Compute the DFT of the input sequence of length N
• 4. None of the above

The radix-2 DIF FFT algorithm is an example of a:

• 1. Divide-and-conquer algorithm
• 2. Dynamic programming algorithm
• 3. Greedy algorithm
• 4. None of the above

Compute the 4-point DFT of the sequence x[n] = [1, 2, 3, 4] using the radix-2 DIF FFT algorithm.

• 1. [10, -2 + 2j, -2, -2 - 2j]
• 2. [10, -2 - 2j, -2, -2 + 2j]
• 3. [10, -2 + 2j, -2, 2 - 2j]
• 4. [10, -2 - 2j, -2, 2 + 2j]