EC: Electronics & Communication Engineering. Duration: Three Hours Maximum Marks: There are a total of 65 questions carrying 100 marks.

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1 EC: Electronics & Communication Engineering Duration: Three Hours Maximum Marks: 100 Read the Instructions carefully. 1. This question paper contains 16 pages. 2. All Questions in this Paper are Objective type. 3. There are a total of 65 questions carrying 100 marks. 4. Questions 1 25 will carry 1-mark each, questions carry 2-marks each. 5. Questions (2 pairs) are common data questions and question pairs (52 53) and (54 55) are linked answer questions. The answer to the second questions of the linked answer question depends on the answer to the first question of the pair. If the first question is wrongly answered or is un-attempted, then the answer to the second question will not be evaluated. 6. Questions belong to general aptitude (GA). Questions will carry 1-mark each, and questions will carry 2-marks each. The GA questions will begin on a fresh page starting from page Un-attempted questions will carry zero marks. 8. Wrong answers will carry NEGATIVE marks. For Questions 1 25 and Questions 56 60, 1/3 mark will be deducted for each wrong answer. For Questions and Questions 61 65, 2/3 mark will be deducted for each wrong answer. 9. The questions pairs (52 53) and (54 55) are questions with linked answers. There will be negative marks only for wrong answers to the first question of the linked answer question pair i.e. for Question 52 and 54, 2/3 will be deducted for wrong answer. There is no negative marking for Question 53 and 55. id: queries@gatecounsellor.com Page 1 of 16

2 Questions 1-25 carry 1 Mark each. 1. Determine the poles of the function 0, -2, 2. is an orthogonal matrix 1. is also an orthogonal matrix 2. is also an orthogonal matrix 3. Neither nor are orthogonal Which of the above statements is/are true? Only 1 Only 2 (D) 0 1, 2, 4 and 5 (D) All of the above 3. Which of the following is true about given ODE The ordinary differential equation(ode) Is of the first order and first degree Is of the second order but of second degree Is of first order but of second degree (D) Is of second order and of second degree 4. General formula for Newton Raphson method is (D) A and C both 5. If emitter injection efficiency of a BJT is 0.98 and its common base dc current gain is 0.96, then the base transport factor is (D) id: queries@gatecounsellor.com Page 2 of 16

3 6. The unity gain frequency for a MOSFET increase with increase in channel length increase with increase in transistor width increase with decrease in channel length (D) stays constant for all channel length 7. Two signals and having Fourier Transforms and shown in figure are combined to form. 1 5 f(khz) f(khz) The minimum sampling frequency for the signal is: 60 khz 120 khz 240 khz (D) 30 khz 8. If X and Y are the zero-mean independent Gaussian random variables with common variance, then the pdf of the phase of Z = X + iy will be: Gaussian Rayleigh Uniform (D) Nakagami 9. Let an angle-modulated signal be given by. Considering is a FM signal with frequency deviation =, find 10. An 8 bit DAC gives an output voltage of when input code is , then the output of DAC when input code is will be (D) None of these 11. Consider the following statements, a. High threshold logic(htl) is designed from Diode transfer Logic(DTL) gate with use of one Zener diode. b. Direct coupled transistor logic(dctl) exhibits current hogging phenomena c. Problem of variable load is overcome by the totem pole arrangement. Then correct statements are (D) All a and b a and c (D) b and c id: queries@gatecounsellor.com Page 3 of 16

4 12. What is the addressing mode of XTHL instruction? GATECounsellor RcPP4 Implicit Register direct Register indirect (D) Memory direct 13. For a Si p-n junction diode the static resistance in terms of diode voltage and current is (D) None of these 14. Which of the following amplifier suffers from crossover distortion Class A Class B Both & (D) None of these 15. The wavelength of the wave propagating in the a waveguide is Smaller than the free space wavelength Greater than the free space wavelength Directly proportional to the group velocity (D) Inversely proportional to the phase velocity 16. Which of these is Poisson s equation for the linear isotropic, but inhomogeneous medium (D) 17. Image theory is applicable to problem involving Electrostatic field only Magnetostatic field only Both Electrostatic field and magnetostatic field (D) Neither Electrostatic field nor magnetostatic field 18. Consider the following statements, with reference to Fourier transform I. Periodic in the one domain results in discrete in the other domain (Here domain refer to time or frequency) Aperiodic in one domain results in continuous in the other domain and vice- II. versa. I & II are wrong I is wrong, II is correct I & II are correct (D) I is correct, II is wrong id: queries@gatecounsellor.com Page 4 of 16

5 19. Find the IFT of 2 jt 1 j t 1 j t (D) 1 j2 t 20. Match the following. I. Wave II. Dimension i. Speech a. One dimensional ii. Image iii. T.V. Picture iv. Temperature i a, ii b, iii c, iv d i b, ii c, iii d, iv a b. Two dimensional c. Three dimensional d. Four dimensional i b, ii d, iii a, iv c (D)i a, ii c, iii b, iv d 21. The Nyquist plot of the open loop transfer function(oltf) is shown in figure, The range of the for the system stability is (D) None 22. For a stable system, gain margin and phase margin should be Positive and negative respectively Negative and positive respectively Both positive (D) Both negative id: queries@gatecounsellor.com Page 5 of 16

6 23. The block diagram for a particular control system is shown in the figure, Low pass system All pass system Minimum phase system (D) High pass system 24. When an AC source of emf is connected across a circuit, the phase difference across the and in the circuit is. The correct combination of the circuit element is (D) 25. In the circuit shown, the network N1 and N2 contains DC sources and resistances. The voltage across 5Ω resistor is given by 5 V 10 V 35 V (D) Cannot be determined id: queries@gatecounsellor.com Page 6 of 16

7 Questions carry 2 Marks each. 26. We have What is the nature of solution of this system of equations? Consistent and unique solution Inconsistent Infinite Solution (D) A and C 27. A Water treatment plant dispatched water bottles for consumption of individuals in a city. Later it was found that water was infected. If the probability of harming (infection) is 0.001, determine the chance that out of 2,000 individuals more than two will get a infection (D) Find the complete solution of (D) 29. Consider the statements below: I. BJT is a current controlled device while FET is a voltage controlled device. II. Both BJT and FET have current due to both types of charge carriers. I is true, II is false I is false, II is true Both I&II are true (D) Both I&II are false id: queries@gatecounsellor.com Page 7 of 16

8 30. Two constellations are shown below: ) ) Which of these are correct? I. Maximum Probability of error of (i) is greater than (ii) II. Maximum Probability of error of (ii) is greater than (i) III. Maximum Probability of error of (i) and (ii) is equal. IV. Average energy of (i) is greater than (ii) V. Average energy of (ii) is greater than (i) VI. Average energy of (i) and (ii) is equal. III and VI I and VI III and V (D) II and V 31. Let a discrete memoryless source with source alphabet ={ with the probabilities given by = 0.25, = 0.25 and = 0.5. Then the entropy of the extended source with source alphabet where n=2 will be 3/2 3 9/2 (D) Asynchronous counter shown in figure below is 1 Mod-21 Mod-22 Mod-20 (D) Mod-19 id: queries@gatecounsellor.com Page 8 of 16

9 , , represent the 2 s complement representation of which set of numbers? 10, 58, 26 respectively -7, -7, -7 respectively -6, -6, -6 respectively (D) -10,-58, -26 respectively 34. The logic circuit used to generate active low chip select by 8085 µp is shown below. The corresponding range of address is. Given that the logic circuit is designed to select 4KB of memory chip, and A12 Pin is in floating state H 06FF H 0700 H 07FF H Either (a) or (b) (D) None 35. In above diagram, is assumed to be very large & finite. The value of and such that (D) id: queries@gatecounsellor.com Page 9 of 16

10 36. Transistors Q1 and Q2 are matched transistors with VBE(ON)=0.7 V. The load needs a variable current which can range from 0.3 ma to 4mA such that Q2 is always in active region.the value of should lie in the region, 2.1 to 10k 4.5 to 25k 2.3 to 31k (D)8.1 to 11k 37. In the given figure, the low frequency model parameters are and.the angular frequency due to capacitor is given by (D) 38. In order to a have high CMRR in a differential pair amplifier, which must hold true: I. An ideal current source with infinite resistance should be used to bias the transistors. II. There should be no mismatch between the two transistors. I only II only both I &II (D) None 39. In a twin wire transmission line in air, the adjacent voltage maxima are 12.5cm and 27.5 cm. The operating frequency is 200 MHz 1 GHz 2 GHz (D) 6 GHz id: queries@gatecounsellor.com Page 10 of 16

11 40. A Uniform plane wave travelling in air is incident on the plane boundary between air and another dielectric medium with. The reflection coefficient for the normal incidence is (D) Find the value of the integral (D) Consider the following figures: If then find and 1, 8 1, 1/8 1/8, 1 (D) 8, 1/8 43. Find the as n Given 0 (D) Final Value theorem is not applicable here 44. Consider the RLC circuit shown in figure for step input, The overshoot equals 16.1% 16.2% 16.3% (D) 0, since the system is not under damped. id: queries@gatecounsellor.com Page 11 of 16

12 45. Find the current through each source, Given conditions are, 1. When only are acting, 2. When and are acting, 3. When and 4. When only A (D) 4, -2, 2, When the circuit in figure 1 is excited, the voltage across is 4 V. When the same circuit is in figure 2 is excited, the voltage across is. When the circuit in figure 3 is excited, the voltage across will be: (D) Fig 1 Fig 2 Fig 3 id: queries@gatecounsellor.com Page 12 of 16

13 47. A certain circuit has source and current through Z is If the strength of each source as well as the load impedance is doubled, then current through the 2ZΩ load will be, Common Data Questions: (D) Not possible to determine Common Data Questions 48 and 49: 48. Consider a BJT with doping in emitter, base and collector as and respectively. What value of must be applied in base emitter region, so that excess minority carries in base region is 10% of the emitter doping 0.82V 0.71V 0.76V (D) 0.69V 49. If in previous question, the length of depletion region inside base at base-emitter junction and base collector region are 5μm and 10μm respectively and total base width is 50μm. Find new doping level of collector to cause a punch through, assuming width of depletion region in collector region remains constant Common Data Questions 50 and 51: A unity feedback system is shown in figure (a) and the root locus of its characteristic equation is shown in figure (b) (D) fig.(a) fig.(b) id: queries@gatecounsellor.com Page 13 of 16

14 50. If P(-6,0) is a point on the root locus, the variable parameter of the system at P is 10/3 20/3 6 (D) For a UFB system shown in fig.(a) & fig.(b) of Q.50 if the variable parameter, the CLTF of the system is, (D) Linked Questions Statement for Linked Answer Questions 52 and 53 A spread-spectrum communication system has the following parameters: Information bit-duration: 4 ms PN chip duration: 1 µs 52. The processing gain will be: (D) 53. If = 10, then jamming margin will be equal to: 26.1 db 15 db 26 db (D) 15.1 db Statement for Linked Answer Questions 54 and For the circuit shown above & and. For the following conditions on frequency, how the above circuit will behave? (1) (a)low Pass (2) (b) High Pass (3) (c)constant 1 - (b), 2 - (c), 3 -(a) 1- (c),2- (b), 3-(a) 1 - (c), 2 - (a), 3 - (b) (D) 1 - (b), 2 -(a), 3 - (c) 55. In previous question if R1 & C1are interchanged with R2 & C2, then the circuit behaves as a Band reject filter All pass filter Band pass filter (D) High pass filter id: queries@gatecounsellor.com Page 14 of 16

15 General Aptitude (GA) Questions Questions carry one mark each. 56. The question below consists of a pair of related words followed by four pairs of words. Select the pair that best expresses the relation in the original pair. QUISLING : BETRAY taunt : provoke inception : termination juggernaut : crush (D) obstinate : preserve 57. In the following question, a word is given in bold which precedes four more words. Pick the word from the four options which most nearly opposite in meaning to the bold word. RECALCITRANT feckless yielding somber (D) polished 58. In the following question one word-part is given with example, followed by four options. Choose the most appropriate word which best describes the meaning of the given word-part in a word. nov (Ex. novice) Other Draw, pull Sharp (D) New 59. Choose the most appropriate word from the options given below to complete the following sentence: He is speaker, his discourses are always informative and inspirational. an eloquent a novice an amateur (D)an inarticulate 60. A speaks truth 70% of the time; B speaks truth 80% of the time. What is the probability that both are contradicting each other? (D) 0.56 Questions carry two marks each. 61. Find the best correction for the underlined sentence from the four options given below. Under a provision of the Constitution that was never applied, Congress has been required to call a convention for considering possible amendments to the document when formally asked to do it by the legislatures of two-thirds of the states. has never been applied, Congress is required to call a convention to consider possible amendments to the document when formally asked to do so id: queries@gatecounsellor.com Page 15 of 16

16 was never applied, there has been a requirement that Congress call a convention for consideration of possible amendments to the document when asked to do it formally has never been applied, whereby Congress is required to call a convention to consider possible amendments to the document when formally asked to do so (D) was never applied, Congress has been required to call a convention for considering possible amendments to the document when formally asked to do it 62. One afternoon a person left home at 2:45pm according to the watch at home. He reached office at 3:10pm according to the watch at office. He stayed there for 25mins and moved towards home at a speed twice than previous and reached home at 4pm according to the watch at home. Find out by which how much time office watch is either fast or late compared to watch at home? 5min fast 5min late 15min late (D) 10min late liter milk was taken from a container and water of same amount was added to the container. This procedure was repeated for three more times. The ratio of quantity of milk to water in the container was obtained to be 81/47 at the end. What was the quantity of milk in the container originally? 14lt 28lt 35lt (D) 42lt 64. A, B and C start running at the same time and from the same point around a circular track of 70m radius. A and B run clockwise and C counter clockwise. If A meets C every 88 seconds and B meets C every 110 seconds, then after how much seconds does A meets B? (D) Twelve straight lines are drawn in a plane such that no two of them are parallel and no three of them are concurrent. A circle is now drawn in the same plane such that all the points of intersection of all the lines lie inside the circle. What is the number of non-overlapping regions into which the circle is divided? (D) 83 END OF THE QUESTION PAPER id: queries@gatecounsellor.com Page 16 of 16

Electronics Eingineering

Electronics Eingineering 1. The output of a two-input gate is 0 if and only if its inputs are unequal. It is true for (A) XOR gate (B) NAND gate (C) NOR gate (D) XNOR gate 2. In K-map simplification, a