This set of Digital Signal Processing Multiple Choice Questions & Answers (MCQs) focuses on “Classification of Signals”.
1. Which of the following is done to convert a continuous time signal into discrete time signal?
Explanation: A discrete time signal can be obtained from a continuous time signal by replacing t by nT, where T is the reciprocal of the sampling rate or time interval between the adjacent values. This procedure is known as sampling.
2. The deflection voltage of an oscilloscope is a ‘deterministic’
signal. True or False?
Explanation: The behavior of the signal is known and can be represented by a saw tooth wave form. So, the signal is deterministic.
3. The even part of a signal x(t) is:
Explanation: Let x(t)=xe(t)+xo(t)
By adding the above two equations, we get
4. Which of the following is the odd component of the signal x(t)=e(jt)?
Explanation: Let x(t)=e(jt)
=(1/2)*(e(jt) – e(-jt))
5. For a continuous time signal x(t) to be periodic with a period T, then x(t+mT) should be equal to:
Explanation: If a signal x(t) is said to be periodic with period T, then x(t+mT)=x(t) for all t and any integer m.
6. Let x1(t) and x2(t) be periodic signals with fundamental periods T1 and T2 respectively. Which of the following must be a rational number for x(t)=x1(t)+x2(t) to be periodic?
Explanation: Let T be the period of the signal x(t)
Thus, we must have
=>(T1/T2)=(k/m)= a rational number.
7. Let x1(t) and x2(t) be periodic signals with fundamental periods T1 and T2 respectively. Then the fundamental period of x(t)=x1(t)+x2(t) is:
a) LCM of T1 and T2
b) HCF of T1and T2
c) Product of T1 and T2
d) Ratio of T1 to T2
Explanation: For the sum of x1(t) and x2(t) to be periodic the ratio of their periods should be a rational number, then the fundamental period is the LCM of T1 and T2.
8. All energy signals will have an average power of:
d) Cannot be calculated
Explanation: For any energy signal, the average power should be equal to 0 i.e., P=0.
9. x(t) or x(n) is defined to be an energy signal, if and only if the total energy content of the signal is a:
a) Finite quantity
d) None of the mentioned
Explanation: The energy signal should have total energy value that lies between 0 and infinity.
10. What is the period of cos2t+sin3t?
Explanation: Period of cos2t=(2*pi)/2=pi
Period of sin3t=(2*pi)/3
LCM of pi and (2*pi)/3 is 2*pi.
Sanfoundry Global Education & Learning Series – Digital Signal Processing.
To practice all areas of Digital Signal Processing, here is complete set of 1000+ Multiple Choice Questions and Answers.