2015| SET 3 - (ECE GATE Exam) - Previous Question Paper Solution
GATE Exam Previous Year Question Paper Solution Electronics and Communication (ECE) - 2015 (SET 3)
Questions
Choose the correct verb to fill in the blank.
Let us _______.
- introvert
- alternate
- atheist
- altruist
Choose the most suitable one word substitute for the following expression:
Connotation of a road or way
- Pertinacious
- Viaticum
- Clandestine
- Ravenous
Choose the most appropriate word from the options given below to complete the following sentence.
If the athlete had wanted to come first in the race, he ______ several hours every day.
- should practise
- should have practised
- practised
- should be practicing
Ram and Shyam shared a secret and promised to each other that it would remain between them. Ram expressed himself in one of the following ways as given in the choices below. Identify the correct way as per standard English.
- It would remain between you and me.
- It would remain between I and you.
- It would remain between you and I.
- It would remain with me.
If x > y > 1, which of the following must be true?
(1) ln x > ln y
(2) ex > ey
(3) yx > xy
(4) cos x > cos y
- (1) and (2)
- (1) and (3)
- (3) and (4)
- (4) and (1)
Directions: Find the missing sequence in the letter series below.
A, CD, GHI, ?, UVWXY
- LMNO
- MNOL
- MNOP
- NOPQ
Ms. X will be in Bagdogra from 01/05/2014 to 20/05/2014 and from 22/05/2014 to 31/05/2014. On the morning of 21/05/2014, she will reach Kochi via Mumbai. Which of the following statements is logically valid and can be inferred from the above sentences?
- Ms. X will be in Kochi for one day, only in May.
- Ms. X will be in Kochi for only one day in May.
- Ms. X will be only in Kochi for one day in May.
- Only Ms. X will be in Kochi for one day in May.
log tan 1o + log tan 2o + ..... + log tan 89o is
- 1
- $\frac{1}{\sqrt{2}}$
- 0
- – 1
In the following question, the first and the last sentences of the passage are in order and numbered 1 and 6, respectively. The rest of the passage is split into 4 parts and numbered 2, 3, 4 and 5. These 4 parts are not arranged in a proper order. Read these sentences and arrange them in a logical sequence to make a passage. Choose the correct sequence from the given options.
- On Diwali, the family rises early in the morning.
- The whole family, including the young and the old enjoy doing this.
- Children let off fireworks later in the night with their friends.
- At sunset, the lamps are lit and the family performs various rituals.
- Father, mother and children visit relatives and exchange gifts and sweets.
- Houses look pretty with the lighted lamps all around.
- 2, 5, 3, 4
- 5, 2, 4, 3
- 3, 5, 4, 2
- 4, 5, 2, 3
Which of the following 8085 microprocessor programs correctly calculates the product of two 8-bit numbers stored in registers B and C?
- MVI A, 00H
JNZ LOOP
CMP C
LOOP DCR B
HLT - MVI A, 00H
CMP C
LOOP DCR B
JNZ LOOP
HLT - MVI A, 00H
LOOP ADD C
DCR B
JNZ LOOP
HLT - MVI A, 00H
ADD C
JNZ LOOP
LOOP INR B
HLT
The directivity of an antenna array can be increased by adding more antenna elements, as a larger number of elements
- improves the radiation efficiency
- increases the effective area of the antenna
- results in a better impedance matching
- allows more power to be transmitted by the antenna
The impulse response of an LTI system can be obtained by
- differentiating the unit ramp response
- differentiating the unit step response
- integrating the unit ramp response
- integrating the unit step response
If the base width in a bipolar junction transistor is doubled, which of the following statements will be TRUE?
- Current gain will increase.
- Unity gain frequency will increase.
- Emitter-base junction capacitance will increase.
- Early voltage will increase.
In the circuit shown below, diodes D1, D2 and D3 are ideal and the inputs E1, E2 and E3 are "0V" each for logic ‘0’ and "10V" each for logic ‘1’. What logic gate does the circuit represent?
- 3–input OR gate
- 3–input NOR gate
- 3–input AND gate
- 3–input XOR gate
If C is a circle of radius r with centre z0 in the complex z-plane and if n is a non-zero integer, then $\oint_c \frac{dz}{(z - z_0)^{n+1}}$ equals
- 2$\pi$nj
- 0
- $\frac{nj}{2 \pi}$
- 2$\pi$n
The transfer function of a first-order controller is given as Gc (s) = $\frac{K(s+ a)}{S + b}$, where K, a and b are positive real numbers.
The condition for this controller to act as a phase lead compensator is
- a < b
- a > b
- K < ab
- K > ab
The modulation scheme commonly used for transmission from GSM mobile terminals is
- 4–QAM
- 16–PSK
- Walsh–Hadamard orthogonal codes
- Gaussian Minimum Shift Keying (GMSK)
Consider a four-point moving average filter defined by the following equation:
$y[n] = \sum_{i = 0}^3 a_ix[n - i]$
The condition on the filter coefficients that results in a null at zero frequency is
- $a_1$ = $a_2$ = 0; $a_0$ = – $a_3$
- $a_1$= $a_2$ = 1; $a_0$ = – $a_3$
- $a_0$ = $a_3$ = 0; $a_1$ = $a_2$
- $a_1$ = $a_2$ = 0; $a_0$ = $a_3$
For A = $\begin{bmatrix}
\ 1 & tan x \
\ - tan x & 1 \
\end{bmatrix}$, the determinant of AT A-1 is
- sec2 x
- cos4 x
- 1
- 0
The contour on the xy-plane, where the partial derivative of x2 + y2 with respect to y is equal to the partial derivative of 6y + 4x with respect to x, is
- y = 2
- x = 2
- x + y = 4
- x – y = 0
The circuit shown below consists of JK flip-flops, each with an active low asynchronous reset ($\bar{R}_d$ input). The counter corresponding to this circuit is
- a modulo-5 binary up counter
- a modulo-6 binary down counter
- a modulo-5 binary down counter
- a modulo-6 binary up counter
A coaxial cable is made of two brass conductors. The spacing between the conductors is filled with Teflon ($\epsilon$r = 2.1, tan $\delta$= 0). Which of the following circuits can represent the lumped element model of a small piece of this cable having length $\triangle$z?
Suppose x[n] is an absolutely summable discrete-time signal. Its z-transform is a rational function with two poles and two zeroes. The poles are at z = $\pm$2j. Which of the following statements is TRUE for the signal x[n]?
- It is a finite duration signal.
- It is a causal signal.
- It is a non-causal signal.
- It is a periodic signal.
Which of the following processes is preferred to form the gate dielectric (SiO2) of MOSFETs?
- Sputtering
- Molecular beam epitaxy
- Wet oxidation
- Dry oxidation
A network is described by the state model as
The transfer function H(s) $\bigg( = \frac{Y(s)}{U(s)}\bigg)$ is
- $\frac{11s + 35}{(s-2)((s-2)(s+4))}$
- $\frac{11s + 35}{(s-2)((s-2)(s+4))}$
- $\frac{11s + 38}{(s-2)((s-2)(s+4))}$
- $\frac{11s + 38}{(s-2)((s-2)(s+4))}$
The electric field profile in the depletion region of a p-n junction in equilibrium is as shown in the figure. Which of the following statements is NOT TRUE?
- The left side of the junction is n-type and the right side is p-type.
- Both the n-type and p-type depletion regions are uniformly doped.
- The potential difference across the depletion region is 700 mV.
- If the p-type region has a doping concentration of 1015 cm–3, then the doping concentration in the n-type region will be 1016 cm–3.
A three bit pseudo random number generator is as shown in the figure. Initially, the value of output Y $\pm$ Y2 Y1 Y0 is set to 111. The value of output Y after three clock cycles is
- 000
- 001
- 010
- 100
An SR latch is implemented using TTL gates as shown in the figure. The set and reset inputs are provided using the push-button switches. It is observed that the circuit fails to work as desired. The SR latch can be made functional by changing
- NOR gates to NAND gates
- inverters to buffers
- NOR gates to NAND gates and inverters to buffers
- 5 V to ground
Consider the 3 m long lossless air-filled transmission line, as shown in the figure. It has a characteristic impedance of 120$\pi$$\Omega$. It is terminated by a short circuit and is excited with a frequency of 37.5 MHz. What is the nature of the input impedance (Zin)?
- Open
- Short
- Inductive
- Capacitive
A message signal m(t) = Am sin(2$\pi$ fmt) is used to modulate the phase of a carrier Ac cos (2$\pi$ fc t) to get the modulated signal y(t) = Ac cos (2$\pi$ fc t + m(t)). The bandwidth of y(t)
- depends on Am, but not on fm
- depends on fm, but not on Am
- depends on both Am and fm
- does not depend on Am or fm
The complex envelope of the bandpass signal $x(t) = -\sqrt{2}\bigg( \frac{sin \Big(\frac{\pi t}{5}\Big)}{\frac{\pi t}{5}} \bigg) sin(\pi t - \frac{\pi}{4})$ centred about $f = \frac{1}{2}$ Hz, is
- $\bigg( \frac{sin \Big(\frac{\pi t}{5}\Big)}{\frac{\pi t}{5}} \bigg) e^{j \frac{\pi}{4}}$
- $\bigg( \frac{sin \Big(\frac{\pi t}{5}\Big)}{\frac{\pi t}{5}} \bigg) e^{-j \frac{\pi}{4}}$
- $\sqrt{2} \bigg( \frac{sin \Big(\frac{\pi t}{5}\Big)}{\frac{\pi t}{5}} \bigg) e^{j \frac{\pi}{4}}$
- $\sqrt{2} \bigg( \frac{sin \Big(\frac{\pi t}{5}\Big)}{\frac{\pi t}{5}} \bigg)$
A universal logic gate can implement any Boolean function by connecting sufficient number of them appropriately. The three are as follows:
Which of the following statements is TRUE?
- Gate 1 is a universal gate.
- Gate 2 is a universal gate.
- Gate 3 is a universal gate.
- None of the gates shown is a universal gate.
The ABCD parameters of the following 2-port network are
- $\begin{bmatrix} \ 3.5 + j2 & 20.5 \\ \ 20.5 & 3.5 - j2 \\ \end{bmatrix}$
- $\begin{bmatrix} \ 3.5 + j2 & 30.5 \\ \ 0.5 & 3.5 - j2 \\ \end{bmatrix}$
- $\begin{bmatrix} \ 10 & 2 + j0 \\ \ 2 + j0 & 10 \\ \end{bmatrix}$
- $\begin{bmatrix} \ 7 + j4 & 0.4 \\ \ 30.5 & 7 - j4 \\ \end{bmatrix}$
A realization of a stable discrete time system is as shown in the figure. If the system is excited by a unit step sequence input x[n], the response y[n] is
- 4 $\Big(- \frac{1}{3} \Big)^n$u[n] – 5 $\Big(- \frac{2}{3} \Big)^n$u[n]
- 5 $\Big(- \frac{2}{3} \Big)^n$u[n] – 3 $\Big(- \frac{1}{3} \Big)^n$u[n]
- 5 $\Big( \frac{1}{3} \Big)^n$u[n] – 5 $\Big( \frac{2}{3} \Big)^n$u[n]
- 5 $\Big( \frac{2}{3} \Big)^n$u[n] – 5 $\Big( \frac{1}{3} \Big)^n$u[n]
