Digital Signal Processing lab VIVA Questions with Answers:


Digital Signal Processing

1.Classify signals?

  1. Continuous time, continuous amplitude (Analog Signals)
  2. Discrete time, continuous amplitude
  3. Continuous time, discrete amplitude
  4. Discrete time, discrete amplitude

2.What is the use of Random Signals?
Random signals are used to test dynamic response statistically for very small amplitudes and time duration.

3. Classify Systems.
Linear, stable and time invariant.

4.What do you mean by aliasing in digital signal processing? How it can be avoided?

  • Aliasing refers to an effect due to which different signals become indistinguishable. It also refers to distortion in the reconstructed signal when it is reconstructed from the original continuous signal.
  • To avoid aliasing we can simply filter out the high freuency components of the signal by using antialiasing filter like optical antialiasing filter.


5. What are the differences between a microprocessor and a DSP processor?
DSP processors are featured to support high performance and repeatitive and intensive tasks whereas microprocessors are not application specific and they are designed to process controloriented tasks.

6. What is the convolution?
Convolution is the technique of adding two signals in time domain. We can also do this uite easily by changing the domain of signals from time domain to freuency domain using Fast Fourier Transform (FFT).

7. What is FFT?
FFT is a fast way to calculate Discrete Fourier Transform (DFT). It is much more efficient then DFT and reuire less number of coding lines. Due to FFT several kind of techniues are feasible.

 8. What is the advantage of a Direct form II FIR over from I?
Direct Form II FIR filters requires half the number of delay units as much as used by Form I.

9. What is interpolation and decimation?
Interpolation is the process of increasing the sample rate in dsp whereas decimation is the opposite of this that is, it is the process of decreasing the sample rate in dsp.

10. Difference between DFT and DTFT.

DFT                                                                                     DTFT
1.Limited number of samples of periodic signal                          1.unlimited number of samples.
2.input is always periodic                                                          2.input may not always be periodic
3 physically realizable                                                          3 mathematically precise
4 frequency becomes discrete                                                  4 frequency is continuous


11.What is a Digital Signal Processor (DSP)?
Microprocessor specifically designed to perform fast DSP operations (e.g., Fast Fourier Transforms, inner products, Multiply & Accumulate)
•Good at arithmetic operations (multiplication/division)
•Mostly programmed with Assembly and C through Integrated Development Environment (IDE)