1

GATE ECE 2007

MCQ (Single Correct Answer)

+2

-0.6

An input to a 6-level quantizer has the probability density function f(X) as shown in the figure. Decision boundaries of the quantizer are chosen so as to maximize the entropy of the quantizer output. It is given that 3 consecutive decision boundaries are ‘-1’, ‘0’ and ‘1’.

Assuming that the reconstruction levels of the quantizer are the mid-points of the decision boundaries, the ratio of signal power to quantization noise power is

2

GATE ECE 2007

MCQ (Single Correct Answer)

+2

-0.6

Two 4-ray signal constellations are shown. It is given that $${\phi _1}$$ and $${\phi _2}$$ constitute an orthonormal basis for the two constellations. Assume that the four symbols in both the constellations are equiprobable. Let $${{{N_0}} \over 2}$$ denote the power spectral density of white Gaussian noise.

The ratio of the average energy of Constellation 1 to the average energy of Constellation 2 is

3

GATE ECE 2007

MCQ (Single Correct Answer)

+2

-0.6

Two 4-ray signal constellations are shown. It is given that $${\phi _1}$$ and $${\phi _2}$$ constitute an orthonormal basis for the two constellations. Assume that the four symbols in both the constellations are equiprobable. Let $${{{N_0}} \over 2}$$ denote the power spectral density of white Gaussian noise.

If these constellations are used for digital communications over an AWGN channel, then which of the following statements is true?

4

GATE ECE 2006

MCQ (Single Correct Answer)

+2

-0.6

In the following figure the minimum value of the constant “C”, which is to be added to y

_{1}(t) such that y_{1}(t) and y_{2}(t) are different, isQuestions Asked from Noise In Digital Communication (Marks 2)

Number in Brackets after Paper Indicates No. of Questions

GATE ECE 2016 Set 1 (2)
GATE ECE 2015 Set 2 (1)
GATE ECE 2015 Set 1 (2)
GATE ECE 2014 Set 4 (2)
GATE ECE 2014 Set 2 (1)
GATE ECE 2013 (1)
GATE ECE 2012 (2)
GATE ECE 2011 (2)
GATE ECE 2010 (2)
GATE ECE 2009 (2)
GATE ECE 2008 (1)
GATE ECE 2007 (5)
GATE ECE 2006 (2)
GATE ECE 2005 (3)
GATE ECE 2004 (1)
GATE ECE 2003 (2)
GATE ECE 2001 (1)
GATE ECE 1999 (2)
GATE ECE 1988 (2)
GATE ECE 1987 (1)

GATE ECE Subjects

Network Theory

Control Systems

Electronic Devices and VLSI

Analog Circuits

Digital Circuits

Microprocessors

Signals and Systems

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

Communications

Electromagnetics

General Aptitude