Broad band communication BIT-IV, MCA, MIT-III
One mark Questions:
1. In LOS the radio wave propagation takes place between two ___ isotropic antennas.
A) logic b) isolated c) broad d) none
2. The power received by the receiving antenna is ___
A) Pr = Sr*Pr b) Pr=Sr*Ar c) P=SA d) none
3. The effective area of an antenna with directivity is ____.
A) b) c) d)
4. For isotropic antenna Gr =___
A) 3 b) 4 c) 1 d) none
5. For isotropic antenna Ar = ___.
A) b) c) d)
6. Pr = _______
A) b) c) d)
7. Free space loss Lfs = Pt / Pr =_______.
A) b) c) d)
8. Lfs in dB is __________.
A) b) c) d)
9. Satellite communication is a good example for ______ space propagation.
A) free b) control c) dynamic d) none
10. If directive antennas are used in place of isotropic antennas then
( Pr / Pt ) directive = ____.
A) b) c) d)
11. Lfsg = _______
A) b) c) d)
12. Lfsg(dB) = _______.
A) b) c) d)
13. K= ____ for a paraboloid .
A) 0.45 b) 9.07 c) 3.4 d) none
14. Lfsg = ______.
A) b) c) d)
15. The power received by the receiver antenna is given by Pr(dBW) = _____.
A) b) c) d)
16. Power density at the receiver is Sr(dB) =______.
A) Pr (dBW) – Ar ( dB) b) Pr(dbW) –P(dc) c) V / R d) none
18. If the field strength at the receiver is Er then Sr =_____.
A) b) c) d)
19. Ar (dB) = __________.
A) b) c) d)
20. Ar = _____.
A) b) c) d)
21. Er = ______.
A) b) c) d)
22. Er units will be in _____.
A) V/m b) V/2m c) M/V d) none
23. On reflection at the partially conducting ground the amplitude and _____of the reflected
are changed.
A) freuency b) amplitude c) phase d) none
24. The complex field strength of the reflected wave Er to that of the incident wave Ei is called _____.
A) rho b) mho c) ohm d) volts
25. rho = _______
A) b) c) d)
26. ______ is also a function of polarization , conductivity etc.
A) rho ` b) ohm c) volts d) none
27. The formula for rho h = ________.
A) b) c) d)
28. For most cases rho h is similarly eual to rho v which is eual to ____.
A) one b) two c) three d) four
29. The path length for the direct wave d1 = _______.
A) b) c) d)
30. The path length for the reflected wave d2= ________.
A) b) c) d)
32. The path difference between direct and reflected wave is _____.
A) b) c) d)
33. Because of the path difference the reflected wave is retarded in phase with respect to direct wave by an angle given by = _______.
A) b) c) d)
34. The total field at the receiver antenna E LOS is given by ______.
A) b) c) d)
35. Modulus of Elos = ________.
A) b) c) d)
36. Elos = ________.
A) b) c) d)
37. 1+ ae = _________
A) b) c) d)
38. 1 + ae = ______.
A) b) c) d)
39. rho = e = _______.
A) –1 b) –5 c) –3 d) none
40. In general case Elos = ________.
A) b) c) d)
41. shy / 2 = _______.
A) b) c) d)
42. do = _______.
A) b) c) d)
43. At a fixed fre and for constant antenna heights as the receiving antenna is brought from the infinity the sine function increases from ______.
A) zero b) one c) –10 d) 20 log 10
44. Elos = ______.
A) b) c) d)
45. Elos is proportional to ________.
A) 1/d2 b) 2/2d c) 3/r d) 2/3
46. At d =do/3, Elos = _______.
A) 2Efs b) 3Efs c) 4Fs d) 4Gs
47. At d = do/6 Elos = _______.
A) zero b) one c) three d) Efs
48. Elos is maximum at _______.
A) all b) do/9 c) do/15 d) do/3all
49. Elos is minimum at _______.
A) all b) do/6 c) do/12 d) do/18
50. Elos = _________.
A) b) c) d)
51. when hro = _________ then | Elos | = |Efs|
A) b) c) d)
52. The first maximum for Elos is reached at height hr = _____.
A) b) c) d)
53. The minimum value for Elos is reached at hr = ______.
A) 6hro b) 4hro c) 9hro d) none
54. Variations in | Elos| is observed when the freuency is varied when the freuency is varied keeping ht and hr constant at f = _________.
A) b) c) d)
55. |Elos| max occurs at f= _______.
A)3fo b) 9fo c)15fo d) all
56. |Elos| minimum occurs at f = ______.
A) 6fo b) 12fo c) 18fo d) all
57. If the reflecting objects are not sufficiently removed from the direct ray path the reflected wave would tend to _____ the direct wave at the receiver.
A) cancel b) add to c) combine d) none
58. The path difference between the direct ray and reflected ray path is given by delta = _____.
A) T+R-TR B) TR-T+R C) TY-OR+E D) NONE
59. The phase difference shy = ______.
A) b) c) d)
60. The reflection produce a phase difference of ______ radians.
A) 180 b) 90 c) 270 d) 360
61. If delta is zero then the ellipsoid degenerates into a ______ line.
A) straight b) circular c) suare d) rectangular
62. If delta is odd multiple of lamba /2 the reflected wave and direct wave are in ____ and maxima occurs.
A) phase b) same amplitude c) direct contact d) none
63. If delta is even multiple of lamba/2 then the reflected wave and direct waves differ in phase by ____ radians.
A) 180 b) 360 c) 270 d) none
64 . The radius of the Fresnel zone is given by ____.
A) B) C) D)
65. The radius of the first Fresnel zone is given by _____.
A) b) c) d)
66. In most practical cases the path clearance is so chosen that |ELOS| = _____.
A) b) c) d)
67. When the path clearance is so chosen that |Elos| = |Efs| then this correspondence to the path clearance of ____.
A) r 0.6 b) r0.9 c) r0.7 d) r0.3
68. shy = ________.
A) b) c) d)
69. |Elos| / |Efs| = ________.
A) b) c) d)
70. The earth is assumed to be a sphere of radius _________.
A) 6367 km b) 6367m c) 6367 miles d) 6367 cm
71. The distance up to which an antenna can see is called _______.
A) radio horizon b) freuency horizon c) space horizon d) wave length
72. The normal value of K is _____.
A) 4/3 b) ¾ c) ½ d) 5/4
73. The maximum distance between two antennas from geometrical consideration is _______.
A) 4.1205 | | b) 3.345* ELOS c) 1000 Km d) none
74. The effect of the curvature of the earth is to _____ the antenna height.
A) reduce b) increase c) infinite d) none
75. The effect of the curvature of the earth results from the fact that the convexity of the earths surface makes the beam from the transmitter antenna more ________.
A) divergent b) contraction c) complicated d) none
76. | ELOS | = ___________-.
A) b) c) d)
77. A uantitative analysis of the Divergence factor D is ____.
A) b) c) d)
78. The incident energy gets scattered or diffused resulting in an apparent decrease in the magnitude of rho due to _______.
A) vegetation b) buildings c) both a & b d) none
79. The effect of ____ is to pull down the maximum and fill up the minimum
A) rho b) mho c) ohm d) wavelength
80. Using Ragleigh criterion a surface may be regarded as smooth only if the phase shift is less than ____ radius.
A) pi/4 b) pi/5 c) pi/10 d) 2/pi
81. The surface may be regarded smooth if ______.
A) b) c) d)
82. Due to the presence of mixture of gases , water vapour , temperature and pressure , humidity there is a variation of___________.
A) refractive index b) freuency c) wave length d) none
85. Under normal condition the value of is _________.
A) negative b) positive c) neutral d) none
86. The value of K is ____ unity.
A) greater than b) less than c) eual to d) none
87. The value of K depends on the gradient of and hence the metrological conditions.
A) eta b) beta c) alpha d) gama
88. Water vapour shows maximum absorption around lamba = _______.
A) 1.3cm b) 2.5cm c) 5cm d) 4.34cm
89. The attenuation due to thick fog, of 65Km hop at lamba greater than 3cm is ________.
A) 4.2dB b) 2.4dB c) 4.92dB d) none
90. ________ phenomena observed in radio propagation are due to variation of the eta of air as height increases.
A) atmospheric refraction b) space reflection c) freuency variation d) none
91. Under normal conditions the eta of atmosphere decreases with height, thus causing the EM waves to bend downward so that they can be received at points beyond the optical ____.
A) LOS b) loss c) gain d) none
92. Transmitter power tends to decrease as the freuency _______-.
A) increases b) decreases c) changes d) none
93. The FDM signal comprises a number of telephony channel arranged side by side in the ____.
A) base band b) conduction band c) carrier band d) none
94. By using FM with deviation ratio ___a substantial improvement in SNR can be obtained.
A) >1 b) <1 c) = 1 d) none
95. An RF oscillator is Freuency modulated by ________.
A) Klystron oscillator b) phase discriminator c) noise suppressor d) none
96. The _______ are of the non modulating type to avoid an increase in distortion and noise.
A) repeater b) controller c) suppressor d) none
97. The terminal receivers are almost invariably of the _____ type with freuency stabilized local oscillator.
A) super heterodyne b) phase sifted c) controller d) none
98. A _______feed is used to provide some discrimination between transmitted and received signals on the same antenna.
A) bipolar b) polar c) uni-polar d) none
99. Microwave LOS transmission is subject to ________ which is due to variable atmosphere bending and multi-path transmission.
A) statistical fading b) increase c) change d) none
100. A common method of improving reliability and performance or of reducing the fading margin is the use of _______ diversity.
A) both b & c b) space c) freuency d) none
101. _______ reuires extra antennas.
A) space diversity b) freuency c) both a & b d) none
102. ________ refers to systems in which one has available two or more closely similar, but statistically uncorrelated copies of some desired signal.
A) diversity system b) digital signals c) freuency changover d) none
103. ________ communications use freuency and space diversity.
A) troposcatter b) inoscatter c) stratosphere d) none
104. Freuency diversity reuires ________ antenna.
A) one b) two c) three d) none
105. In _____, freuency marking has the advantage over polarization marking that it eliminates the need for high power duplexers.
A) space diversity b) ultra high c) infra red d) none
TWO MARKS UESTIONS:
1. ____ channel make a group and _____ channel make a super group.
A) 12,60 b) 60,12 c) 12,120 d) 15,60
2. commonly used antennas for LOS are ____ and _____.
A) parabolic b) horn c) a & b d) only a
3. Lfsg = ________.
A) b) c) d)
4. G(dB) = ________
A) b) c) d)
5. Er (dB) = _______
A) b) c) d)
6. Calculate the free space path Loss of a 100 Km LOS link if operating freuency is 10 GHz
A) 152.4418 b) 162.4418 c) 4418.152 d) 512
7. In a 10 super group the number of channels are ____ and the freuency limit is ___.
A) 600, 2540KHz b) 500,34Hz c) 45, 43Hz d) 600, 2540MHz
8. Each telephony channel transmits audio freuencies from 300 Hz to 3.4KHz , the base band signals being in the form of ____ signals with suppressed carriers at ____ intervals.
A) SSB , 4 KHz b) VSB, 8KHz c) FM, 4KHz d) none
FOUR MARKS UESTIONS:
1. Calculate the necessary clearance for the FFZ. Given that the distance of the obstacle from the transmitter dt = 20 Km , and from the Rx , dr=30Km , measured along the LOS . The freuency of transmission is 3 GHz.
A) 34.64m b) 45.8Km c) 34.5Km d) none
2. If the FFZ is given by 34.64m and the distance of the obstacle from the transmitter is dt = 20Km
And from the Rx ,dr=30 Km , measured along the LOS. Then find the freuency of transmission?
A) 4GHz b) 5GHz c) 3 GHz d) none
3. A satellite at a distance 400 Km from a point on the earth’s surface radiates a power of 2 watts, from the antenna with a gain of 1.7 dB in the direction of the observer. The receiving antenna has a gain of 52.3 dB. Find the received power ,if the satellite operates at a freuency of 11 GHz.
A) 12.5 dBW b) 3000 watts c) 128.3dBW d) none
4. Given the distance of the obstacle from the transmitter dt=20Km , and the second FZ clearance = 40 meters. Find the distance of the obstacle from the receiver ?. The freuency of transmission is 4 GHz .
A) 111.045 Km b) 11.034Km c) 20log 5 d) none
5. calculate the free space path loss of a 100 Km LOS link if operating freuency is 10 GHZ.
A) 192.448 dB b) 142.4418 dB c) 152.4418 dB d) none
SATELLITE COMMUNATIONS:
ONE MARK UESTIONS:
1. Three satellites spaced ___ degrees apart could cover the whole world.
a) 120 b) 180 c) 230 d) none
2. With _____satellites it is possible to establish communications link over wider area as the
Satellite covers wider area.
A) geosynchronous b) elliptical c) round d) none
3. Satellite communications applications for ____ orbits is limited
A) lower b) upper c) zigzag d) none
4. The first commercial geosynchronous satellite was _____.
A) Intelsat 1 b) agni c) rohini d) none
5. The “Intelsat 1” is also called as ____.
A) early bird b) country bird c) eagle bird d) none
6. The early bird was launched on ___
A) April 6 1965 b) November 3 1995 c) May 5 199 d) none
7. Birthday of commercial satellite ____
A) June 28 1965 b) May 25 2000 c) Jan 23 1967 d) none
8. A geosynchronous orbit should have _____ velocity
A) constant b) irregular c) negative d) none
9. From Kepler third law of planetary motion gives ___.
A) b)
c) d)
10. Kepler’s constant is _____
A) 3.986 b) 4.98 c) 4.67 d) none
11. Earth rotational period is ___ hours
A) 24 b) 34 c) 32 d) 12
12. Geosynchronous orbit distance is ____ Km away from earth.
A) 36000 b) 38000 c) 42,242 d) none
13. Geosynchronous orbit distance is ___ Km away from the center of the earth
A) 42,242 b) 45,342 c) 78,763 d) none
14. In geosynchronous orbit tracking of the antenna is not necessary because ___
A) satellite appears stationary b) of automatic controls
C) satellite uses extra fuel d) none
15. In ____ there is no need of switch from one satellite to other and therefore on break in
Transmission.
A) geosynchronous b) elliptical c) round d) none
16. One satellite is capable of covering of ____ percent
A) 40 b) 60 c) 12 d)25
17. In geosynchronous regions of earth above _____ degrees i.e. Polar regions cannot be covered.
A) 80 b) 30 c) 23 d) none
18. Because of large distance the signal suffers a delay of__ milli seconds in a two way comunications.
A) 540 b) 270 c) 370 d) 400
19. For a space craft to achieve synchronous orbit, it must be accelerated to a velocity of ___ meters per second.
A) 3070 b) 2070 c) 4070 d) 3700
20. ELV stands for ___
A) expendable launch vehicle b) extra launch vehicle
C) entire launch vehicle d) none
21. Satellite has two freuencies
a) uplink,down link b) uplink, control link
c) control link,up link d) none
22. Commonly used bands for the uplink freuencies are ___GHz and ___ GHz
A) 6,14 b) 5,56 c) 54,21 d) 89,23
23. The down link freuency is ____ than up link freuency
A) lower b) higher c) same d) none
24. Commonly used bands in the down link freuency are __ GHz, ___GHz and _____GHz.
A) 4,12,20 b) 3,4,5 c) 1,5,3 d) 8,7,4
25. Two different freuencies are used for up link and for down link to avoid ____.
A) interference b) change in freuency c) control of satellite d) none
26. _____ freuency is always chosen to be greater than down link freuency to be able to focus on to a small antenna on the satellite.
A) uplink b) down link c) control link d) system
27. When we express 4/6 GHz it means 4 GHz ____link freuency and 6 GHz ____link freuency.
A) up , down b) down, up c) control , system d) none
28. The following bands of freuencies are used in satellite communication.
UHF =____ and Ku = _______ and Ka=______.
A) 470 – 890MHz , 11.7-14.5 HHz , 17-31HHz b) 470MHz,45KHz,35KHz
C) 45Hz, 45Hz,67Hz d) none
29. A satellite receives radio signals in a given freuency band , ____ their freuency and retransmits them.
A) changes b) controls c) divides d) none
30. Terrestrial LOS link distance is about _____Km.
A) 50 b) 100 c) 200 d) 500
31. Satellite link distance is about ____Km.
A) 36,000 b) 56000 c) 35000 d) 23000
32. The telephone user waits for the reply of the person he is talking for an extra ___ milli seconds if the call goes via satellite in both direction.
A) 540 b) 450 c) 270 d) 340
33. 4/6 GHz is _____band.
A) C b) D c) A d) B
34. The received signal from the satellite is ____ Watts.
A) Pico b) 10 c) 30 d) 100
35. The unit normally used for expressing signal attenuation is ___.
A) decibel b) power c) voltage d) Ampere
36. If P1 is larger power and P2 is smaller power then attenuation in decibel is ___
A) b)
c) d)
37. In free space the power loss of the signal can be expressed as _____.
A) b)
c) d)
38. If the antennas used for transmission and reception has a gain of say Gt and Gr respectively then L=_______.
A) b)
c) d)
39. For an antenna with a diameter d the gain at freuency f is given by _____.
A) b)
c) d)
40. Consider 4/6 GHz link , the earth station antenna has 30 m diameter and antenna on the satellite has 1.5m diameter, therefore up link losses are ____ and down l ink losses are __
A) 99.7, 103.6 db b) 45,34 db c) 45,23 db d) 78,45db
41. ______ consists of rocket motors that are used to move the satellite back to the correct orbit when external forces cause it to drift off the station.
A) AOCS b) BOAS c) YTOS d) BBOS
42. The ____ system corrects the position and altitude of the space craft.
A) control b) communication c) video d) none
43 The communication system mainly the transmitters reuire power. Other electrical systems on the spacecraft referred to a ______.
A) house keeping system b) home audio system c) control system d) none
44. All the electrical power is derived in the satellite using ____.
A) solar cells b) battery c) diesel generator d) none
45. The power from the solar cells is ____ before use partly to compensate for the decrease in the array output and partly to provide the different voltages and currents needed by various components.
A) conditioned b) divided c) decreased d) converted to AC
46. The solar cell generates power of the order of few _____ Watts.
A) 100 b) 500000 c) 4000 d) 33000
47. During _____ the solar cells do not receive the sunlight and stop functioning.
A) eclipse b) night c) rainy day d) winter
48. Transmitter and Receiver set is known as _____
A) transponder b) cyber space c) space charge d) none
49. It is desirable to have highly ______ antenna to get higher signal gains.
A) directional b) subsystem c) spacious d) none
50. The satellite actually acts as a _____ and hence needs transmitter and receiver.
A) repeater b) amplifier c) converter d) none
SATELLITE COMMUNICATION
FOUR MARKS UESTIONS:
1. choose the correct statement for a communication sub system
1) transponder is a freuency down converter and repeater
2) uplink freuency is greater than down link freuency
3) Altitude and orbit control is done by the gas jets controlled by command sub-system
4) The angular velocity of earth is eual to the angular velocity of a Geosynchronous satellite.
A) 1,2 b) 1,3 c) 1,3,4 d) 1,2,3,4
2. The main causes of fading in free space propagation are ____.
1) earth’s curvature
2) efficiency of transmitter and receiver
3) atmospheric absorption
4) scattering due to rain or fog
5) atmospheric refraction
a) 1,2,3 b) 1,4 c) 3,4,5 d) 2,3
3. If the freuency of link between earth station and satellite is 4/6 GHz with ground antenna diameter = 30 and satellite antenna diameter is 1.5 m. Then uplink and down link losses in dB are _____.
A) 99.7 dB , 100 dB b) * 99.7 dB , 103.6 dB
C) 100 dB , 99.7 dB d) 99.7 dB , 90 dB
4. For a satellite to achieve geostationary orbit , it must satisfy which of the following conditions.
1) It must have a constant angular velocity
2) Satellites rotational period should match with that of earths rotational period
3) It must be raised to a distance of 36,500 Km from the center of the earth
4) It must be accelerated to a velocity of 3070 m/sec
5) Orbit should lie in earth’s euatorial plane
A) 1,2,3 b) 2,5 c) 3,4 d) 1,4
OPTICAL FIBER COMMUNICATIONS: -
ONE MARK UESTIONS:
1. In a communication system information is superimposed on to an electromagnetic wave acting as ____.
A) carrier b) control wave c) transmitted wave d) none
2. Communications is also achieved using electromagnetic carrier in ____ range of freuencies.
A) optical b) audio c) control d) none
3. The information is used to vary the intensity of light and the modulated light is guided by the ______ .
A) optical fiber b) co-axial wire c) twisted pair d) flat cable
4. The optical fiber communication system makes use of light freuency range of about _____ micrometer to ____ micrometer wavelength band.
A) 0.6, 1.6 b) 6,7 c) 8,9 d) 50,89
5. Commonly used optical sources are _____ and ____.
A) LED, LASER b) LED, LDR c) amplifier, oscillator d) none
6. The ___ produces an electrical current proportional to the light input.
A) detector b) microphone c) camera d) speaker
7. Commonly used detectors are ____ and ____.
A) PIN, APD b) LED, LASER c) APD, LASER d) none
8. The ______guides the light and then at the receiving end, light from the fiber is coupled to a detector.
A) fiber b) current c) magnetic field d) electric field
9. The light carrier freuency in optical fiber is in the range of ten-power ____ to ten power ____.
A) 13,16 b) 1,5 c) 5,7 d) 3,5
10. Actually in optical communication system, the _____is not limited by the optical fiber but by the electronic system used at the terminal stations.
A) bandwidth b) amplitude c) phase d) none
11. Optical fiber is made up of _____.
A) insulator b) copper c) ceramic d) none
12. There are no possibilities of ____ or ___ hazard in optical fiber.
A) arching, spark b) transmission, control c) none
13. Optical materials are made up of ____ materials.
A) dielectric b) conducting c) semiconductors d) none
14. Optical fiber is free from _____ interference.
A) electromagnetic b) light c) data rate d) none
15. ____ is totally removed in optical fiber.
A) cross talk b) data c) bandwidth d) none
16. Optical fibers are ___ to external interference.
A) immune b) effected c) adaptable d) none
17. Optical fiber has ____ transmission loss.
A) less b) high c) no d) none
18. There is no ____ interference between two fibers.
A) optical b) data c) bandwidth d) none
19. Attenuation in optical fiber is _____dB/ Km.
A) 0.2 b) 0.8 c) 5 d) none
20. There is no _____ outside the optical fiber.
A) radiation b)
FOUR MARKS FIBER OPTICS
1. For a PIN photo detector
N uantum efficiency is 65 %
charge on electron 1.6* 10 power minus 19
H planks constant 6.625 * 10 power minus 34
P optical power of incidance 0.5 watts
V freuency of photon is 10 power 17
Then find the current through the load resistor
A) 16 amps b) 3 amps c) 14 amps d) none
2. For a graded index fiber normalized freuency = 4 and the constant of the fiber
alpha =2 then the number of modes the fiber can support is ____.
A) 8 b) 4 c) 7 d) 10
3. If the refraction index of the medium is 1.0 . Then the dielectric constant of that medium will be ______.
A) 1.2 b) 1.3 c) *1.1 d 1.5
4. choose the correct statements
1) febry parrot cavity in a laser is to increase the intensity
2) laser is less power full than LED
3) refractive index is constant in graded indeed fiber
4) refractive index is not constant in step index fiber
a) 1 b) 3,4,5 c) 2,3,5 d) all
5. In a photo diode the efficiency at 1550 nm is 0.65. What is the primary current if 0.6 W of optical power falls on the diode.
A) 486 micro ampere b) 48.6 micro amperes
C) 4.86 micro amperes d) 48.6 milli amperes
Answers
B B C UNIT I ONE MARK ANSWERS 2 marks 4 marks
1 B 21 B 41 B 61 A 81 A 101 A 1 A
2 B 22 A 42 C 62 A 82 A 102 A 2 C 1 A
3 A 23 C 43 A 63 A 83 B 103 A 3 D 2 C
4 C 24 A 44 B 64 B 84 A 104 A 4 B 3 C
5 C 25 A 45 A 65 B 85 A 105 5 A 4 B
6 A 26 A 46 A 66 B 86 A 6 A 5 C
7 B 27 A 47 A 67 A 87 A 7 A
8 A 28 A 48 A 68 B 88 A 8 A
9 A 29 B 49 A 69 B 89 A
10 B 30 A 50 A 70 A 90 A
11 A 31 b 51 A 71 A 91 A
12 D 32 B 52 C 72 A 92 A
13 D 33 B 53 A 73 A 93 A
14 B 34 A 54 D 74 A 94 A
15 A 35 C 55 A 75 A 95 A
16 A 36 B 56 A 76 A 96 A
17 37 A 57 A 77 A 97 A
18 B 38 B 58 A 78 A 98 A
19 A 39 A 59 D 79 A 99 A
20 B 40 B 60 A 80 A 100 A
UNIT 2 SATELLITE COMMUNICATION :
ONE MARK FOUR MARKS
1 A 21 A 41 A
2 A 22 A 42 A 1 A
3 A 23 A 43 A 2 C
4 A 24 A 44 A 3 B
5 A 25 A 45 A 4 C
6 A 26 A 46 A
7 A 27 B 47 A
8 A 28 A 48 A
9 D 29 A 49 A
10 A 30 A 50 A
11 A 31 A
12 A 32 A
13 A 33 A
14 A 34 A
15 A 35 A
16 A 36 C
17 A 37 A
18 A 38 A
19 A 39 B
20 40 A
UNIT 3 OPTICAL COMMUNICATION :
ONE MARK
1 A 11 A FOUR MARKS
2 A 12 A 1 D
3 A 13 A 2 B
4 A 14 A 3 C
5 A 15 A 4 A
6 A 16 A 5 C
7 A 17 A
8 A 18 A
9 A 19 A
10 20 D
