GATE EC 2023: Electronics and Communication Engineering
Text of page 1
Electronics and Communication Engineering (EC)
General Aptitude (GA)
Q.1 – Q.5 Carry ONE mark Each
Q.1 “I cannot support this proposal. My ________ will not permit it.”
(A) conscious
(B) consensus
(C) conscience
(D) consent
Q.2 Courts : _______ : : Parliament : Legislature
(By word meaning)
(A) Judiciary
(B) Executive
(C) Governmental
(D) Legal
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.3 What is the smallest number with distinct digits whose digits add up to 45?
(A) 123555789
(B) 123457869
(C) 123456789
(D) 99999
Q.4 In a class of 100 students,
(i) there are 30 students who neither like romantic movies nor comedy movies,
(ii) the number of students who like romantic movies is twice the number of
students who like comedy movies, and
(iii) the number of students who like both romantic movies and comedy movies
is 20.
How many students in the class like romantic movies?
(A) 40
(B) 20
(C) 60
(D) 30
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.5 How many rectangles are present in the given figure?
. .
(A) 8
(B) 9
(C) 10
(D) 12
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Electronics and Communication Engineering (EC)
Q.6 – Q.10 Carry TWO marks Each
Q.6 Forestland is a planet inhabited by different kinds of creatures. Among other
creatures, it is populated by animals all of whom are ferocious. There are also
creatures that have claws, and some that do not. All creatures that have claws are
ferocious.
Based only on the information provided above, which one of the following options
can be logically inferred with certainty?
(A) All creatures with claws are animals.
(B) Some creatures with claws are non-ferocious.
(C) Some non-ferocious creatures have claws.
(D) Some ferocious creatures are creatures with claws.
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.7 Which one of the following options represents the given graph?
(A) −x
f ( x ) = x2 2
(B) −x
f ( x ) = x. 2
(C)
f ( x ) = x 2− x
(D)
f ( x ) = x. 2− x
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.8 Which one of the following options can be inferred from the given passage alone?
When I was a kid, I was partial to stories about other worlds and
interplanetary travel. I used to imagine that I could just gaze off into space
and be whisked to another planet.
[Excerpt from The Truth about Stories by T. King]
(A) It is a child’s description of what he or she likes.
(B) It is an adult’s memory of what he or she liked as a child.
(C) The child in the passage read stories about interplanetary travel only in parts.
(D) It teaches us that stories are good for children.
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.9 Out of 1000 individuals in a town, 100 unidentified individuals are covid positive.
Due to lack of adequate covid-testing kits, the health authorities of the town devised
a strategy to identify these covid-positive individuals. The strategy is to:
(i) Collect saliva samples from all 1000 individuals and randomly group
them into sets of 5.
(ii) Mix the samples within each set and test the mixed sample for covid.
(iii) If the test done in (ii) gives a negative result, then declare all the 5
individuals to be covid negative.
(iv) If the test done in (ii) gives a positive result, then all the 5 individuals
are separately tested for covid.
Given this strategy, no more than _______ testing kits will be required to identify
all the 100 covid positive individuals irrespective of how they are grouped.
(A) 700
(B) 600
(C) 800
(D) 1000
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Electronics and Communication Engineering (EC)
Q.10 A 100 cm × 32 cm rectangular sheet is folded 5 times. Each time the sheet is folded,
the long edge aligns with its opposite side. Eventually, the folded sheet is a rectangle
of dimensions 100 cm × 1 cm.
The total number of creases visible when the sheet is unfolded is _______.
(A) 32
(B) 5
(C) 31
(D) 63
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Electronics and Communication Engineering (EC)
Q.11 – Q.35 Carry ONE mark Each
Q.11 1 2
Let v1 = [2] and v2 = [1] be two vectors. The value of the coefficient α in the
0 3
expression v1 = αv2 + e, which minimizes the length of the error vector e, is
(A) 7
2
(B) −2
7
(C) 2
7
(D) −7
2
Q.12 The rate of increase, of a scalar field f(x, y, z) = xyz, in the direction v = (2,1,2)
at a point (0,2,1) is
(A) 2
3
(B) 4
3
(C) 2
(D) 4
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Electronics and Communication Engineering (EC)
Q.13 Let w 4 = 16j. Which of the following cannot be a value of w?
j2π
(A)
2e 8
jπ
(B)
2e 8
j5π
(C)
2e 8
j9π
(D)
2e 8
Q.14 z+2
The value of the contour integral, ∮C (z 2 +2z+2) dz , where the contour C is
3
{z: |z + 1 − 2 j| = 1}, taken in the counter clockwise direction, is
(A) −π(1 + j)
(B) π(1 + j)
(C) π(1 − j)
(D) −π(1 − j)
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Q.15 Let the sets of eigenvalues and eigenvectors of a matrix B be {λk | 1 ≤ k ≤ n} and
{vk | 1 ≤ k ≤ n}, respectively. For any invertible matrix P, the sets of eigenvalues
and eigenvectors of the matrix A, where B = P −1 AP, respectively, are
(A) {λk det(A) | 1 ≤ k ≤ n} and {Pvk | 1 ≤ k ≤ n}
(B) {λk | 1 ≤ k ≤ n} and {vk | 1 ≤ k ≤ n}
(C) {λk | 1 ≤ k ≤ n} and {Pvk | 1 ≤ k ≤ n}
(D) {λk | 1 ≤ k ≤ n} and {P−1 vk | 1 ≤ k ≤ n}
Q.16 In a semiconductor, if the Fermi energy level lies in the conduction band, then the
semiconductor is known as
(A) degenerate n-type.
(B) degenerate p-type.
(C) non-degenerate n-type.
(D) non-degenerate p-type.
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Electronics and Communication Engineering (EC)
Q.17 For an intrinsic semiconductor at temperature T = 0 K, which of the following
statement is true?
(A) All energy states in the valence band are filled with electrons and all energy states
in the conduction band are empty of electrons.
(B) All energy states in the valence band are empty of electrons and all energy states
in the conduction band are filled with electrons.
(C) All energy states in the valence and conduction band are filled with holes.
(D) All energy states in the valence and conduction band are filled with electrons.
Q.18 A series RLC circuit has a quality factor Q of 1000 at a center frequency of
106 rad/s. The possible values of R, L and C are
(A) R = 1 Ω, L = 1 μH and C = 1 μF
(B) R = 0.1 Ω, L = 1 μH and C = 1 μF
(C) R = 0.01 Ω, L = 1 μH and C = 1 μF
(D) R = 0.001 Ω, L = 1 μH and C = 1 μF
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Electronics and Communication Engineering (EC)
Q.19 For a MOS capacitor, Vfb and Vt are the flat-band voltage and the threshold voltage,
respectively. The variation of the depletion width (Wdep ) for varying gate voltage
(Vg ) is best represented by
(A) wdep
vfb vt vg
accumulation depletion inversion
(B) wdep
vfb vt vg
accumulation depletion inversion
(C) wdep
vfb vt vg
accumulation depletion inversion
(D) wdep
vfb vt vg
accumulation depletion inversion
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Electronics and Communication Engineering (EC)
Q.20 Consider a narrow band signal, propagating in a lossless dielectric medium
(εr = 4, μr = 1), with phase velocity vp and group velocity vg . Which of the
following statement is true? (c is the velocity of light in vacuum.)
(A) vp > c, vg > c
(B) vp < c, vg > c
(C) vp > c, vg < c
(D) vp < c, vg < c
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Electronics and Communication Engineering (EC)
Q.21 In the circuit shown below, V1 and V2 are bias voltages. Based on input and output
impedances, the circuit behaves as a
VDD
V1
vOUT
V2
R1
vIN
(A) voltage controlled voltage source.
(B) voltage controlled current source.
(C) current controlled voltage source.
(D) current controlled current source.
Q.22 A cascade of common-source amplifiers in a unity gain feedback configuration
oscillates when
(A) the closed loop gain is less than 1 and the phase shift is less than 180°.
(B) the closed loop gain is greater than 1 and the phase shift is less than 180°.
(C) the closed loop gain is less than 1 and the phase shift is greater than 180°.
(D) the closed loop gain is greater than 1 and the phase shift is greater than 180°.
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Electronics and Communication Engineering (EC)
Q.23 In the circuit shown below, P and Q are the inputs. The logical function realized by
the circuit shown below is
I0
2×1 Y
MUX
P I1
Sel
Q
(A) Y = PQ
(B) Y=P+Q
(C) Y = ̅̅̅̅
PQ
(D) Y = ̅̅̅̅̅̅̅
P+Q
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Electronics and Communication Engineering (EC)
Q.24 The synchronous sequential circuit shown below works at a clock frequency of
1 GHz. The throughput, in Mbits/s, and the latency, in ns, respectively, are
Input Output
D0 Q0 D1 Q1 D2 Q2
D D D
Flip Flop Flip Flop Flip Flop
CLK = 1 GHz
(A) 1000, 3
(B) 333.33, 1
(C) 2000, 3
(D) 333.33, 3
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Q.25 The open loop transfer function of a unity negative feedback system is
k
G(s) = s(1+sT )(1+sT ) , where k, T1 and T2 are positive constants. The phase cross-
1 2
over frequency, in rad/s, is
(A) 1
√T1 T2
(B) 1
T1 T2
(C) 1
T1 √T2
(D) 1
T2 √T1
Q.26 Consider a system with input x(t) and output y(t) = x(e t ). The system is
(A) Causal and time invariant.
(B) Non-causal and time varying.
(C) Causal and time varying.
(D) Non-causal and time invariant.
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Electronics and Communication Engineering (EC)
Q.27 Let m(t) be a strictly band-limited signal with bandwidth B and energy E.
Assuming ω0 = 10B, the energy in the signal m(t) cos ω0 t is
(A) E
4
(B) E
2
(C) E
(D) 2E
2
Q.28 The Fourier transform X(ω) of x(t) = e −t is
∞ 2
Note: ∫−∞ e −y dy = √π
(A) ω2
√π e 2
(B) ω2
e− 4
2√π
(C) ω2
−
√π e 4
(D) ω2
−
√π e 2
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Q.29 In the table shown below, match the signal type with its spectral characteristics.
Signal type Spectral characteristics
(i) Continuous, aperiodic (a) Continuous, aperiodic
(ii) Continuous, periodic (b) Continuous, periodic
(iii) Discrete, aperiodic (c) Discrete, aperiodic
(iv) Discrete, periodic (d) Discrete, periodic
.
(A) (i) → (a), (ii) → (b), (iii) → (c), (iv) → (d)
(B) (i) → (a), (ii) → (c), (iii) → (b), (iv) → (d)
(C) (i) → (d), (ii) → (b), (iii) → (c), (iv) → (a)
(D) (i) → (a), (ii) → (c), (iii) → (d), (iv) → (b)
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Q.30 For a real signal, which of the following is/are valid power spectral
density/densities?
(A) 2
SX (ω) =
9 + ω2
2
(B) SX (ω) = e −ω cos2 ω
(C) SX(ω )
1
0 ω
-1
(D) SX(ω )
1
0 ω
Q.31 The signal-to-noise ratio (SNR) of an ADC with a full-scale sinusoidal input is
given to be 61.96 dB. The resolution of the ADC is ________ bits (rounded off to
the nearest integer).
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Electronics and Communication Engineering (EC)
Q.32 In the circuit shown below, the current i flowing through 200 Ω resistor is ______
mA (rounded off to two decimal places).
1 mA
i
1 kΩ
2V
1 mA
2 kΩ 200 Ω
2 kΩ
Q.33 For the two port network shown below, the [Y]-parameters is given as
1 2 −1
[Y] = [ ]S
100 −1 4/3
The value of load impedance ZL, in Ω, for maximum power transfer will be _______
(rounded off to the nearest integer).
10 Ω
120 V +_ [Y]
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Q.34 For the circuit shown below, the propagation delay of each NAND gate is 1 ns. The
critical path delay, in ns, is __________ (rounded off to the nearest integer).
A Q
Q
B
Q.35 In the circuit shown below, switch S was closed for a long time. If the switch is
opened at t = 0, the maximum magnitude of the voltage VR, in volts, is _________
(rounded off to the nearest integer).
2Ω
S
1Ω VR
1H
Vs = 2 V
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Q.36 – Q.65 Carry TWO marks Each
Q.36 A random variable X, distributed normally as N(0,1), undergoes the transformation
Y = h(X), given in the figure. The form of the probability density function of Y is
(In the options given below, a, b, c are non-zero constants and g(y) is piece-wise
continuous function)
y = h(x)
1
x
-2 -1 1 2
-1
(A) aδ(y − 1) + bδ(y + 1) + g(y)
(B) aδ(y + 1) + bδ(y) + cδ(y − 1) + g(y)
(C) aδ(y + 2) + bδ(y) + cδ(y − 2) + g(y)
(D) aδ(y + 2) + bδ(y − 2) + g(y)
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Q.37 Q
The value of the line integral ∫P (z 2 dx + 3y 2 dy + 2xz dz) along the straight line
joining the points P (1,1,2) and Q (2,3,1) is
(A) 20
(B) 24
(C) 29
(D) -5
Q.38 Let x be an n × 1 real column vector with length l = √xT x. The trace of the matrix
P = xxT is
(A) l2
(B) l2
4
(C) l
(D) l2
2
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Q.39 V
The VOUT of the circuit shown below is
IN
R2
VCC
R1 R4
_
vIN
+
VCC
R3 _
-VEE
+ vOUT
VCC R3
+
-VEE
_
R1
-VEE
R2
(A) R4
−
R3
(B) R4
R3
(C) R4
1+
R3
(D) R4
1−
R3
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Q.40 In the circuit shown below, D1 and D2 are silicon diodes with cut-in voltage of 0.7 V.
VIN and VOUT are input and output voltages in volts. The transfer characteristic is
D1
VIN VOUT
1 kΩ
D2
+
_ 1V
(A) VOUT
1
1
VIN
0.3 1.7
1
(B) VOUT
1
- 0.7
VIN
0.7
1
(C) VOUT
1
1
VIN
1 -1.7 1.7
(D) VOUT
1
VIN
0.3 1.7
1
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Q.41 A closed loop system is shown in the figure where k > 0 and α > 0. The steady state
error due to a ramp input (R(s) = α/s2 ) is given by
k Y(s)
2 E(s)
R(s) = α /s s(s+2)
(A) 2α
k
(B) α
k
(C) α
2k
(D) α
4k
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Q.42 In the following block diagram, R(s) and D(s) are two inputs. The output Y(s) is
expressed as Y(s) = G1 (s)R(s) + G2 (s)D(s).
G1 (s) and G2 (s) are given by
D(s)
Y(s)
G(s)
R(s)
H(s)
(A) G(s) G(s)
G1 (s) = and G2 (s) =
1 + G(s) + G(s)H(s) 1 + G(s) + G(s)H(s)
(B) G(s) G(s)
G1 (s) = and G2 (s) =
1 + G(s) + H(s) 1 + G(s) + H(s)
(C) G(s) G(s)
G1 (s) = and G2 (s) =
1 + G(s) + H(s) 1 + G(s) + G(s)H(s)
(D) G(s) G(s)
G1 (s) = and G2 (s) =
1 + G(s) + G(s)H(s) 1 + G(s) + H(s)
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Q.43 The state equation of a second order system is
ẋ (t) = Ax(t), x(0) is the initial condition.
Suppose λ1 and λ2 are two distinct eigenvalues of A and v1 and v2 are the
corresponding eigenvectors. For constants α1 and α2 , the solution, x(t), of the state
equation is
(A) 2
∑ αi e λi t vi
i=1
(B) 2
∑ αi e 2λi t vi
i=1
(C) 2
∑ αi e 3λi t vi
i=1
(D) 2
∑ αi e 4λi t vi
i=1
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Q.44 The switch S1 was closed and S2 was open for a long time. At t = 0, switch S1 is
opened and S2 is closed, simultaneously. The value of ic (0+ ), in amperes, is
S1 ic 100 Ω S2
1A 0.01 F 25 Ω
1H
(A) 1
(B) −1
(C) 0.2
(D) 0.8
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Q.45 Let a frequency modulated (FM) signal
t
x(t) = A cos(ωc t + kf ∫−∞ m(λ)dλ) , where m(t) is a message signal of bandwidth
W. It is passed through a non-linear system with output y(t) = 2x(t) + 5(x(t))2 .
Let BT denote the FM bandwidth. The minimum value of ωc required to recover
x(t) from y(t) is
(A) BT + W
(B) 3
B
2 T
(C) 2BT + W
(D) 5
B
2 T
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Q.46 The h-parameters of a two port network are shown below. The condition for the
V
maximum small signal voltage gain Vout is
s
i1 h11 i2
v1 h22 RL
h12v2 v2
h21v1 Vout
Vs
(A) h11 = 0, h12 = 0, h21 = very high and h22 = 0
(B) h11 = very high, h12 = 0, h21 = very high and h22 = 0
(C) h11 = 0, h12 = very high, h21 = very high and h22 = 0
(D) h11 = 0, h12 = 0, h21 = very high and h22 = very high
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Q.47 Consider a discrete-time periodic signal with period N = 5. Let the discrete-time
jk2πn
Fourier series (DTFS) representation be x[n] = ∑4k=0 ak e 5 , where a0 = 1, a1 =
4πn
3j, a2 = 2j, a3 = −2j and a4 = −3j. The value of the sum ∑4n=0 x[n] sin 5 is
(A) −10
(B) 10
(C) −2
(D) 2
Q.48 Let an input x[n] having discrete time Fourier transform
X(e jΩ ) = 1 − e −jΩ + 2e −3jΩ be passed through an LTI system. The frequency
1
response of the LTI system is H(e jΩ ) = 1 − 2 e −j2Ω . The output y[n] of the system
is
(A) 1 5
δ[n] + δ[n − 1] − δ[n − 2] − δ[n − 3] + δ[n − 5]
2 2
(B) 1 5
δ[n] − δ[n − 1] − δ[n − 2] − δ[n − 3] + δ[n − 5]
2 2
(C) 1 5
δ[n] − δ[n − 1] − δ[n − 2] + δ[n − 3] − δ[n − 5]
2 2
(D) 1 5
δ[n] + δ[n − 1] + δ[n − 2] + δ[n − 3] + δ[n − 5]
2 2
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Q.49 Let x(t) = 10 cos(10.5Wt) be passed through an LTI system having impulse
sin Wt 2
response ℎ(t) = π ( πt ) cos 10Wt . The output of the system is
(A) 15W
( ) cos(10.5Wt)
4
(B) 15W
( ) cos(10.5Wt)
2
(C) 15W
( ) cos(10.5Wt)
8
(D) (15W) cos(10.5Wt)
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Q.50 Let x1 (t) and x2 (t) be two band-limited signals having bandwidth
B = 4π × 103 rad/s each. In the figure below, the Nyquist sampling frequency, in
rad/s, required to sample y(t), is
cos(4π×103t)
x1(t)
cos(12π×103t) y(t)
x2(t)
(A) 20π × 103
(B) 40π × 103
(C) 8π × 103
(D) 32π × 103
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Q.51 The S-parameters of a two port network is given as
S S12
[S] = [ 11 ]
S21 S22
with reference to Z0 . Two lossless transmission line sections of electrical lengths
θ1 = βl1 and θ2 = βl2 are added to the input and output ports for measurement
purposes, respectively. The S-parameters [S′] of the resultant two port network is
(A) S e −j2θ1 S12 e −j(θ1 +θ2 )
[ 11 −j(θ +θ ) ]
S21 e 1 2 S22 e −j2θ2
(B) S e j2θ1 S12 e −j(θ1 +θ2 )
[ 11 −j(θ +θ ) ]
S21 e 1 2 S22 e j2θ2
(C) S e j2θ1 S12 e j(θ1 +θ2 )
[ 11 j(θ +θ ) ]
S21 e 1 2 S22 e j2θ2
(D) S e −j2θ1 S12 e j(θ1 +θ2 )
[ 11 j(θ +θ ) ]
S21 e 1 2 S22 e −j2θ2
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Q.52 The standing wave ratio on a 50 Ω lossless transmission line terminated in an
unknown load impedance is found to be 2.0. The distance between successive
voltage minima is 30 cm and the first minimum is located at 10 cm from the load.
ZL can be replaced by an equivalent length lm and terminating resistance Rm of the
same line. The value of Rm and lm , respectively, are
(A) Rm =100 Ω, lm = 20 cm
(B) Rm = 25 Ω, lm = 20 cm
(C) Rm =100 Ω, lm = 5 cm
(D) Rm = 25 Ω, lm = 5 cm
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Q.53 The electric field of a plane electromagnetic wave is
E = ax C1x cos(ωt − βz) + ay C1y cos(ωt − βz + θ) V/m.
Which of the following combination(s) will give rise to a left handed elliptically
polarized (LHEP) wave?
(A) C1x = 1, C1y = 1, θ = π/4
(B) C1x = 2, C1y = 1, θ = π/2
(C) C1x = 1, C1y = 2, θ = 3π/2
(D) C1x = 2, C1y = 1, θ = 3π/4
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Electronics and Communication Engineering (EC)
Q.54 The following circuit(s) representing a lumped element equivalent of an
infinitesimal section of a transmission line is/are
(A) LΔz RΔz
CΔz/2 GΔz/2
(B) LΔz RΔz
GΔz CΔz
(C) LΔz RΔz
GΔz/2 CΔz/2 GΔz/2 CΔz/2
(D) RΔz/2 LΔz/2 LΔz/2 RΔz/2
GΔz CΔz
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.55 The value of the integral ∬R xy dx dy over the region R, given in the figure, is
_______ (rounded off to the nearest integer).
y
2
y = x+2 y = -x+2
1 R
y = -x y=x
O x
Q.56 In an extrinsic semiconductor, the hole concentration is given to be 1.5ni where ni
is the intrinsic carrier concentration of 1 × 1010 cm−3. The ratio of electron to hole
mobility for equal hole and electron drift current is given as __________ (rounded
off to two decimal places).
Q.57 The asymptotic magnitude Bode plot of a minimum phase system is shown in the
k(s+z)a
figure. The transfer function of the system is (s) = b c , where k, z, p, a, b and
s (s+p)
c are positive constants. The value of (a + b + c) is __________(rounded off to the
nearest integer).
-20 dB/decade
|G(jω )| in dB
-40 dB/decade
ω1 ω2 log ω
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.58 Let x1 (t) = u(t + 1.5) − u(t − 1.5) and x2 (t) is shown in the figure below. For
∞
y(t) = x1 (t) ∗ x2 (t), the ∫−∞ y(t)dt is ______________________(rounded off to
the nearest integer).
x2(t)
2
1 1
-3 -2 -1 0 1 2 t
Q.59 1
Let X(t) be a white Gaussian noise with power spectral density 2 W/Hz. If X(t) is
input to an LTI system with impulse response e −t u(t). The average power of the
system output is ___________ W (rounded off to two decimal places).
Q.60 A transparent dielectric coating is applied to glass (εr = 4, μr = 1) to eliminate the
reflection of red light (λ0 = 0.75 μm). The minimum thickness of the dielectric
coating, in μm, that can be used is _________ (rounded off to two decimal places).
Q.61 In a semiconductor device, the Fermi-energy level is 0.35 eV above the valence band
energy. The effective density of states in the valence band at T = 300 K is
1 × 1019 cm−3 . The thermal equilibrium hole concentration in silicon at 400 K is
____________ × 1013 cm−3 (rounded off to two decimal places).
Given kT at 300 K is 0.026 eV.
Q.62 A sample and hold circuit is implemented using a resistive switch and a capacitor
with a time constant of 1 μs. The time for the sampling switch to stay closed to
charge a capacitor adequately to a full scale voltage of 1 V with 12-bit accuracy is
_______ μs (rounded off to two decimal places).
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.63 In a given sequential circuit, initial states are Q1 = 1 and Q2 = 0. For a clock
frequency of 1 MHz, the frequency of signal Q2 in kHz, is ___________ (rounded
off to the nearest integer).
D1 Q1 D2 Q2
D D
Flip Flop Flip Flop
Q1 Q2
CLK = 1 MHz
Q.64 In the circuit below, the voltage VL is ____________ V (rounded off to two decimal
places).
VDD
W/L = 10 W/L = 7
W/L = 1
VL
W/L = 10 W/L = 5 1 kΩ
1 mA
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Organizing Institute: IIT Kanpur
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Electronics and Communication Engineering (EC)
Q.65 The frequency of occurrence of 8 symbols (a-h) is shown in the table below. A
symbol is chosen and it is determined by asking a series of “yes/no” questions which
are assumed to be truthfully answered. The average number of questions when asked
in the most efficient sequence, to determine the chosen symbol, is _______ (rounded
off to two decimal places).
Symbols a b c d e f g h
Frequency 1 1 1 1 1 1 1 1
of 2 4 8 16 32 64 128 128
occurrence
.
END OF QUESTION PAPER
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Organizing Institute: IIT Kanpur
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GATE 2023 Electronics and Communication Engineering (EC)
Question Type (QT)
Q. No. Session Subject Name (SN) Key/Range (KY) Mark (MK)
MCQ/MSQ/NAT
1 4 MCQ GA C 1
2 4 MCQ GA A 1
3 4 MCQ GA C 1
4 4 MCQ GA C 1
5 4 MCQ GA C 1
6 4 MCQ GA D 2
7 4 MCQ GA A 2
8 4 MCQ GA B 2
9 4 MCQ GA A 2
10 4 MCQ GA C 2
11 4 MCQ EC C 1
12 4 MCQ EC B 1
13 4 MCQ EC A 1
14 4 MCQ EC B 1
15 4 MCQ EC C 1
16 4 MCQ EC A 1
17 4 MCQ EC A 1
18 4 MCQ EC D 1
19 4 MCQ EC B 1
20 4 MCQ EC D 1
21 4 MCQ EC D 1
22 4 MCQ EC MTA 1
23 4 MCQ EC A 1
24 4 MCQ EC A 1
25 4 MCQ EC A 1
26 4 MCQ EC B 1
27 4 MCQ EC B 1
28 4 MCQ EC C 1
29 4 MCQ EC B 1
30 4 MSQ EC A,B 1
31 4 NAT EC 10 to 10 1
32 4 NAT EC 1.30 to 1.40 1
33 4 NAT EC 80 to 80 1
34 4 NAT EC 02 to 02 1
35 4 NAT EC 04 to 04 1
36 4 MCQ EC B 2
37 4 MCQ EC B 2
38 4 MCQ EC A 2
39 4 MCQ EC A 2
40 4 MCQ EC A 2
41 4 MCQ EC A 2
42 4 MCQ EC A 2
43 4 MCQ EC A 2
44 4 MCQ EC B 2
45 4 MCQ EC B 2
Text of page 2
46 4 MCQ EC MTA 2
47 4 MCQ EC A 2
48 4 MCQ EC C 2
49 4 MCQ EC A 2
50 4 MCQ EC D 2
51 4 MCQ EC A 2
52 4 MSQ EC B,C 2
53 4 MSQ EC A,B,D 2
54 4 MSQ EC B,C,D 2
55 4 NAT EC 0 to 0 2
56 4 NAT EC 2.20 to 2.30 2
57 4 NAT EC 4 to 4 2
58 4 NAT EC 15 to 15 2
59 4 NAT EC 0.24 to 0.26 2
60 4 NAT EC 0.12 to 0.14 2
61 4 NAT EC 60.00 to 70.00 2
62 4 NAT EC 8.30 to 8.34 2
63 4 NAT EC 250 to 250 OR 500 to 500 2
64 4 NAT EC 2.00 to 2.00 2
65 4 NAT EC 1.97 to 1.99 2
MTA = Marks to ALLPage 1 of 44
Source: GATE. Question paper published by GATE.