## Wednesday, 25 December 2013

### Comprehensive Viva Questions Signals And Systems

Comprehensive Viva Questions Signals And Systems

1.       Every periodic signal is a Power signal & every aperiodic signal is aEnergy signal.
2.      We need low pass filter before sampling is for forBand Limiting (Anti Alias Filter).
3.      The Fourier transform of a triangular pulse is Square Of The Sinc Function
4.      The condition for a system to be causal is H(N) = 0, N<0.
5.      The relationship between correlation and convolution is Cross Correlation Of F(T)And G(T) Is The Same As Convolution Of F(T) And G(-T).
6.      If the random process X (t) is periodic, then auto correlation function is Periodic.
7.      The autocorrelation of a random process Rxx (T) is Even function T.
8.     The autocorrelation function is maximum at T = Zero.
9.      A low pass filter prior to sampling eliminate Aliasing.
10.  A band limited signal means its Fourier transform is zero Above A Certain Frequency.
11.    Aliasing effect is also eliminated when sampling rate is Higher ThanNyquist Frequency.
12.  Band pass signals can be sampled at the minimum rate of Twice The Band Width.
13.  A signal can be completely recovered if sampling rate of fs is >= 2fm Samples Per Second.
14.  Aliasing effect results in Distortion of the signal.
15.   In sampling theorem the ideal low pass filter is called Reconstruction Filter.