1

GATE ECE 2004

MCQ (Single Correct Answer)

+1

-0.3

An AM signal is detected using an envelope detector. The carrier frequency and
modulating signal frequency are 1 MHz and 2 KHz respectively. An appropriate
value for the time constant of the envelope detector is

2

GATE ECE 2004

MCQ (Single Correct Answer)

+1

-0.3

An AM signal and a narrow-band FM signal with identical carriers, modulating
signals and modulation indices of 0.1 are added together. The resultant signal
can be closely approximated by

3

GATE ECE 2002

MCQ (Single Correct Answer)

+1

-0.3

A 1 MHz sinusoidal carrier is amplitude modulated by a symmetrical square wave
of period 100 µsec. Which of the following frequencies will NOT be present in the
modulated signal?

4

GATE ECE 1999

MCQ (Single Correct Answer)

+1

-0.3

A modulated signal is given by, $$s\left(t\right)=m_1\left(t\right)\cos\left(2{\mathrm{πf}}_\mathrm c\mathrm t\right)\;+m_2\left(t\right)\sin\left(2{\mathrm{πf}}_\mathrm c\mathrm t\right)$$, where
the baseband signal m

_{1}(t) and m_{2}(t) have bandwidths of 10 kHz and 15 kHz, respectively. The bandwidth of the modulated signal, in kHz, isQuestions Asked from Analog Communication Systems (Marks 1)

Number in Brackets after Paper Indicates No. of Questions

GATE ECE Subjects

Signals and Systems

Representation of Continuous Time Signal Fourier Series Discrete Time Signal Fourier Series Fourier Transform Discrete Time Signal Z Transform Continuous Time Linear Invariant System Transmission of Signal Through Continuous Time LTI Systems Discrete Time Linear Time Invariant Systems Sampling Continuous Time Signal Laplace Transform Discrete Fourier Transform and Fast Fourier Transform Transmission of Signal Through Discrete Time Lti Systems Miscellaneous Fourier Transform

Network Theory

Control Systems

Digital Circuits

General Aptitude

Electronic Devices and VLSI

Analog Circuits

Engineering Mathematics

Microprocessors

Communications

Electromagnetics