Discrete Fourier Transform-Online Quiz 1

Given that W=e^-i(2π/N) , where N=3. Then F=W^N can be computed as F=

• 0

• 1

• -1

• e

Given that W=e^-i(2π/N) , where N=3. Then F=W^(N/2) can be computed as F=

• 0

• 1

• -1

• e

Which of the following relations are true if x(n) is real?

• X(ω)=X(-ω)

• X(ω)=-X(-ω)

• X*(ω)=X(ω)

• X*(ω)=X(-ω)

The time system which operates with a continuous time signal and produces a continuous time output signal is

• CTF system

• DTF System

• Time invariant System

• Time variant System

DFT is applied to

• Infinite sequences

• Finite discrete sequences

• Continuous infinite signals

• Continuous finite sequences

The circular convolution of two sequences in time domain is equivalent to

• Multiplication of DFTs of two sequences

• Summation of DFTs of two sequences

• Difference of DFTs of two sequences

• Square of multiplication of DFTs of two sequences

The basic properties of DFT includes

1)Linearity

2) Periodicity

3) Circular symmetry

4) Summation

• 1, 2 and 3 are correct

• 1, 2 and 4 are correct

• 1 and 3 are correct

• All the four are correct

The DFT is preferred for

1) Its ability to determine the frequency component of the signal

2) Removal of noise

3) Filter design

4) Quantization of signal

• 1, 2 and 3 are correct

• 1 and 2 are correct

• 1 and 3 are correct

• All the four are correct

DTFT is the representation of

• Periodic Discrete time signals

• Aperiodic Discrete time signals

• Aperiodic continuous signals

• Periodic continuous signals

The transforming relations performed by DTFT are

1)Linearity

2) Modulation

3) Shifting

4) Convolution

• 1, 2 and 3 are correct

• 1, and 2 are correct

• 1 and 3 are correct

• All the four are correct