$(a) x [n] \ (b) x[n-2] \ (c) x[n].u[n-1] \ (d) x[3-n] \ (e) x[n-1].δ[n-1]. $

Mumbai University > EXTC > Sem 4 > Signals and Systems

Marks : 10

Year : MAY 2015

$$(a) x[n]$$

It is the given signal with values $x[n] = \{1,1,1,1,2\}$

$$(b) x[n - 2]$$ It is a delayed signal. We will have to shift x[n] to the right by 2 position. ![enter image description here][2] $$(c) x[n].u[n - 1]$$ u[n] is a unit step signal which is delayed by one sample and is then multiplied with x[n]. The resultant signal will look like the one shown in the figure below. ![enter image description here][3] $$(d) x[3 - n]$$

$x[3 - n] = x[- (n -3)]$

This signal is first delayed by three samples and then time folded. The figure is shown below.

$$(e) x[n - 1].δ[n -1]$$

Unit sample signal is first delayed by one sample. Also, the signal x[n] is delayed by one sample. These two sampled signals are then multiplied. The figure is shown