1
GATE ECE 2017 Set 1
MCQ (Single Correct Answer)
+2
-0.6
Let x(t) be a continuous time periodic signal with fundamental period T = 1 seconds. Let {ak} be the complex Fourier series coefficients of x(t), where k is integer valued. Consider the following statements about x(3t):

I. The complex Fourier series coefficients of x(3t) are {ak} where k is integer valued

II. The complex Fourier series coefficients of x(3t) are {3ak} where k is integer valued

III. The fundamental angular frequency of x(3t) is 6$$\mathrm\pi$$ rad/s

For the three statements above, which one of the following is correct?
A
only II and III are true
B
only I and III are true
C
only III is true
D
only I is true
2
GATE ECE 2017 Set 1
MCQ (Single Correct Answer)
+1
-0.3
Consider the following statements for continuous-time linear time invariant (LTI) system.

I. There is no bounded input bounded output (BIBO) stable system with a pole in the right half of the complex plane.
II. There is no causal and BIBO stable system with a pole in the right half of the complex plane.

Which one among the following is correct?

A
Both $${\rm I}$$ and $${\rm I}{\rm I}$$ are true
B
Both $${\rm I}$$ and $${\rm I}{\rm I}$$ are not true
C
Only $${\rm I}$$ is true
D
Only $${\rm I}{\rm I}$$ is true
3
GATE ECE 2017 Set 1
Numerical
+2
-0
Two discrete-time signals x [n] and h [n] are both non-zero only for n = 0, 1, 2 and are zero otherwise. It is given that x(0)=1, x[1] = 2, x [2] =1, h[0] = 1, let y [n] be the linear convolution of x[n] and h [n]. Given that y[1]= 3 and y [2] = 4, the value of the expression (10y[3] +y[4]) is _____________________.
Your input ____
4
GATE ECE 2017 Set 1
Numerical
+2
-0
A continuous time signal x(t) = $$4\cos (200\pi t)$$ + $$8\cos(400\pi t)$$, where t is in seconds, is the input to a linear time invariant (LTI) filter with the impulse response $$h(t) = \left\{ {{{2\sin (300\pi t)} \over {\matrix{ {\pi t} \cr {600} \cr } }}} \right.\,,\,\matrix{ t \cr t \cr } \,\matrix{ \ne \cr = \cr } \,\matrix{ 0 \cr 0 \cr } $$

Let y(t) be the output of this filter. The maximum value of $$\left| {y(t)} \right|$$ is ________________________.

Your input ____