1
GATE ECE 2020
MCQ (Single Correct Answer)
+2
-0.67
For the modulated signal $x(t)=m(t) \cos \left(2 \pi f_c t\right)$, the message signal $m(t)=4 \cos (1000 \pi t)$ and the carrier frequency $f_c$ is 1 MHz . The signal $x(t)$ is passed through a demodulator, as shown in figure below. The output $y(t)$ of the demodulator is
2
GATE ECE 2017 Set 2
Numerical
+2
-0
The un-modulated carrier power in an AM transmitter is 5kW. This carrier is modulated by a
sinusoidal modulating signal. The maximum percentage of modulation is 50%. If it is reduced
to 40%, then the maximum un-modulated carrier power (in kW) that can be used without
overloading the transmitter is ___________
Your input ____
3
GATE ECE 2017 Set 2
Numerical
+2
-0
A modulating signal given By $$x\left(t\right)=5\sin\left(4\mathrm\pi10^3\mathrm t\;-\;10\mathrm{πcos}2\mathrm\pi10^3\mathrm t\right)$$ V
is fed to a phase modulator
with phase deviation constant kp=0.5rad/V. If the carrier frequency is 20 kHz, the
instantaneous frequency (in kHz) at t = 0.5 ms is __________
Your input ____
4
GATE ECE 2015 Set 1
Numerical
+2
-0
In the system shown in figure (a), m(t) is a low-pass signal with bandwidth W Hz. The
frequency response of the band-pass filter H(f) is shown in figure (b). If it is desired that the
output signal z(t) = 10x(t), the maximum value of W (in Hz) should be strictly less than
____________________.
Your input ____
GATE ECE Subjects
Browse all chapters by subject
General Aptitude
Network Theory
Microprocessors
Signals and Systems
Discrete Fourier Transform and Fast Fourier Transform Discrete Time Signal Fourier Series Fourier Transform Continuous Time Signal Laplace Transform Fourier Transform Representation of Continuous Time Signal Fourier Series Transmission of Signal Through Continuous Time LTI Systems Miscellaneous Sampling Continuous Time Linear Invariant System Discrete Time Linear Time Invariant Systems Discrete Time Signal Z Transform Transmission of Signal Through Discrete Time Lti Systems
Electromagnetics
Digital Circuits
Electronic Devices and VLSI
Control Systems
Communications
Engineering Mathematics