ONLINE EXAMINATIONS [Mid 2 - awp]

1. The length of subsequent directors of yagi - uda antenna reduces progressively by [01D01]
   1. 2.5 %
   2. 13 %
   3. 10 %
   4. 15 %
2. The distance between reflector & driven element in yagi - uda antenna is [01M01]
   1. 
   2. 
   3. 
   4. 
3. Spacing between director and direcor of yagi uda antenna is [01M02]
   1. 
   2. 
   3. 
   4. 
4. The length of reflector of yagi - uda antenna is [01S01]
   1. 0.48 λ
   2. 0.28 λ
   3. 0.18 λ
   4. 0.3λ
5. The driven element in yagi-uda antenna is [01S02]
   1. folded dipole
   2. reflector
   3. lens
   4. horn
6. The length of driven element of yagi -uda antenna in meters is [01S03]
   1. 
   2. 
   3. 
   4. 
7. The length of reflector of yagi -uda antenna in meters is [01S04]
   1. 
   2. 
   3. 
   4. 
8. The length of first director of yagi -uda antenna in meters is [01S05]
   1. 
   2. 
   3. 
   4. 
9. Spacing between reflector and driven element of yagi Uda antenna is [01S06]
   1. 
   2. 
   3. 
   4. 
10. Spacing between director and driven element of yagi uda antenna is [01S07]
    1. 
    2. 
    3. 
    4. 
11. _ _ _ _ _ _ _ polarization results in more signal strength [02D01]
    1. horizontal
    2. vertical
    3. left circular
    4. right circular
12. The diameter of elements in yagi Uda antenna is [02M01]
    1. 1 to 1.2 cm
    2. 2 to 10 cm
    3. 3 to 5 cm
    4. 10 to 20 cm
13. Less reflection & reduced ghost images possible with _ _ _ _ polarized yagi uda [02M02]
    1. horizontal
    2. vertical
    3. left circular
    4. right circular
14. The adverse effect of closer radiators in yagi uda array is [02S01]
    1. lowering of input impedance of array
    2. increasing of input impedance of array
    3. lowering of output impedance of array
    4. constant input impedance of array
15. For maximum pickup, the receiving yagi uda antenna is mounted [02S02]
    1. horizontally
    2. vertically
    3. 30⁰ inclined
    4. 60⁰ inclined
16. A hollow conductor in yagi uda antenna is preferred because of [02S03]
    1. skin effect
    2. miller effect
    3. fermat effect
    4. debye effect
17. In fringe area installation, _ _ _ _ _ _ _ used along with yagi uda antenna to improve reception [02S04]
    1. booster amplifier
    2. buck amplifier
    3. all pass filter
    4. operation amplifier
18. The gain of yagi uda six element antenna for operation at 500 MHz is [02S05]
    1. 11dBi
    2. 20dBi
    3. 100dBi
    4. 5dBi
19. The length of reflector element of yagi uda six element antenna for operation at 500 MHz is [02S06]
    1. 28.8 cm
    2. 40 cm
    3. 100 cm
    4. 10 .8cm
20. For 5 element yogi Uda (UHF & VHF TV channels) reflector length L_R is [02S07]
    1. 0.15 λ
    2. λ
    3. 0.1λ
    4. 2λ
21. The field pattern in the horizontal plane for corner reflector at a distance r from antenna is [03M01]
    1. 
    2. 
    3. 
    4. 
22. If the feed to vertex distance d is made equal to side length L in reflector then the aperture width is [03M02]
    1. 1.414 L
    2. 2L
    3. 1.6L
    4. 1.334L
23. A corner reflector without an exciting antenna can be used as [03S01]
    1. passive reflector
    2. active reflector
    3. lens
    4. dipole
24. The corner angle for passive reflector is [03S02]
    1. 90⁰
    2. 50⁰
    3. 10⁰
    4. 80⁰
25. In grid type of reflector the spacing between conductors is [03S03]
    1. 
    2. 
    3. 
    4. 
26. The height of conductors( for /2 driven element antenna) in grid type of reflector is [03S04]
    1. 
    2. 
    3. 
    4. 
27. Compared to isolated /2 antenna, corner reflector antenna power gain will be _ _ _ _ times higher [03S05]
    1. 10 to 20
    2. 30 to 50
    3. 20 to 60
    4. 40 to 50
28. One of the following uses corner reflector antenna [03S06]
    1. point to point communication
    2. television
    3. radio astronomy
    4. internet
29. If corner angle is 90⁰ then range of corner to dipole spacing is [03S07]
    1. 
    2. 
    3. 
    4. 
30. The relative field pattern E in the plane of the driven λ /2 element of a square corner reflector is [04D01]
    1. 
    2. 
    3. 
    4. 
31. The normalized field pattern E( Ø ) for paraboloid with uniformly illuminated aperture is given by [04D02]
    1. 
    2. 
    3. 
    4. 
32. A square corner reflector has a spacing of λ /4 between the driven /2 element and the corner. The directivity is [04M01]
    1. 12.8 dBi
    2. 15.8 dBi
    3. 121.8 dBi
    4. 19.8 dBi
33. If corner angle is 180⁰ then range of corner to dipole spacing is [04S01]
    1. 
    2. 
    3. 
    4. 
34. A square corner reflector has a driven λ/2 element. The distance between the driven element and corner is λ /2 . The terminal impedance of driven element is [04S02]
    1. 125 ohm
    2. 150 ohm
    3. 100 ohm
    4. 200 ohm
35. A square corner reflector has a driven /2 element. The distance between the driven element and corner is /2 . The half power beam width in θ is [04S03]
    1. 60⁰
    2. 90⁰
    3. 45⁰
    4. 120⁰
36. A square corner reflector has a driven λ /2 element. The distance between the driven element and corner is λ /2 . The half power beam width in Ø is [04S04]
    1. 42⁰
    2. 50⁰
    3. 45⁰
    4. 30⁰
37. A square corner reflector has a driven λ/ 2 element. The distance between the driven element and corner is λ /2 Directivity from impedance of driven & image dipoles is ` [04S05]
    1. 11.9 dBi
    2. 20.9 dBi
    3. 30.9 dBi
    4. 3 dBi
38. A square corner reflector has a driven λ /2 element. The distance between the driven element and corner is λ /2 Directivity from HPBWs is [04S06]
    1. 11.4 dBi
    2. 20.4 dBi
    3. 13.4 dBi
    4. 15.3 dBi
39. For large circular apertures, the beam width between first nulls is [04S07]
    1. 
    2. 
    3. 
    4. 
40. The directivity D of a large uniformly illuminated circular aperture is [05D01]
    1. 
    2. 
    3. 
    4. 
41. The field intensity ratio in the aperture plane for parabolic reflector is [05M01]
    1. 
    2. 
    3. 
    4. 1
42. The beam width between half power points for a large circular aperture is [05S01]
    1. 
    2. 
    3. 
    4. 
43. The F/D for parabolic reflector is [05S02]
    1. 0.25 to 0.5
    2. 0.5 to 5
    3. 5 to 10
    4. 4 to 8
44. The distance from any point P on a parabolic curve to a fixed point F is called [05S03]
    1. focus
    2. vertex
    3. feed point
    4. cassegrain
45. A parabolic reflector have a [05S04]
    1. directional feed
    2. offset feed
    3. vertex feed
    4. isotropic feed
46. To make the field completely uniform across the aperture would require a feed pattern with [05S05]
    1. inverse taper
    2. exponential taper
    3. uniform taper
    4. non uniform taper
47. The loss in aperture due to feed antenna blockage avoided by using [05S06]
    1. offset feed
    2. directional feed
    3. Horn feed
    4. Dipolefeed
48. The flared out wave guide is also known as [05S07]
    1. Horn antenna
    2. Yagi-uda antenna
    3. dipole
    4. paraboloid
49. For optimum horn antenna, optimum length ,L is [06D01]
    1. 
    2. 
    3. 
    4. 
50. If δ = 0.2 , length L = 62.5 , then the pyramidal horn antenna flare angle in E- plane is [06D02]
    1. 9.1⁰
    2. 1⁰
    3. 5⁰
    4. 6⁰
51. For pyramidal horn directivity,D is [06M01]
    1. 
    2. 
    3. 
    4. 
52. Beam width between first nulls for optimum E-plane rectangular Horn is [06M02]
    1. 
    2. 
    3. 
    4. 
53. If a and b are mouth dimensions in Z & Y directions L is horn length from mouth to apex then `a` is [06S01]
    1. 
    2. 
    3. 
    4. 
54. For optimum Horn antenna , optimum δ is [06S02]
    1. 
    2. 
    3. 
    4. 
55. If = 0.2 and E plane aperture a_E = 10 λ , then length L for pyramidal horn is [06S03]
    1. 
    2. 
    3. 
    4. 
56. If E-plane aperture of pyramidal antenna is aE = 10 λ , then HPBW(E-plane) [06S04]
    1. 5.6⁰
    2. 2⁰
    3. 10⁰
    4. 8⁰
57. If H plane aperture of pyramidal antenna is a_H = 13.7 λ , then HPBW(H-plane) [06S05]
    1. 4.9⁰
    2. 10⁰
    3. 6⁰
    4. 2⁰
58. Beam width between first nulls for optimum H- plane rectangular horn is [06S06]
    1. 
    2. 
    3. 
    4. 
59. For pyramidal horn antenna, if h is height in E -plane & w is width in H-plane, the power gain G_p is [07D01]
    1. 
    2. 
    3. 
    4. 
60. If Δ A is elemental area , E is magnitude of radiated field generated by Δ A , d is the distance to Δ A , θ is angle with respect to an axis that is perpendicular to mouth of parabolic antenna then strength of electric field at Δ A is [07D02]
    1. 
    2. 
    3. 
    4. 
61. Beam width between half power points for optimum H-plane rectangular horn is [07M01]
    1. 
    2. 
    3. 
    4. 
62. Typical value of δ for H-plane horn antenna is [07M02]
    1. 0.4
    2. 0.3
    3. 0.1
    4. 1
63. If a and b are mouth dimensions in Z & Y directions L is horn length from mouth to apex. then half power beam widths in degrees in H plane is [07M03]
    1. 
    2. 
    3. 
    4. 
64. Beam width between half power points for optimum E-plane rectangular horn is [07S01]
    1. 
    2. 
    3. 
    4. 
65. If a and b are mouth dimensions in Z & Y directions L is horn length from mouth to apex. Then `b` is [07S02]
    1. 0.81 a
    2. 0.98a
    3. 2a
    4. 0.5a
66. If a and b are mouth dimensions in Z & Y directions L is horn length from mouth to apex .then gain is [07S03]
    1. 
    2. 
    3. 
    4. 
67. If a and b are mouth dimensions in Z & Y directions, L is horn length from mouth to apex. then half power beam widths in degrees in E plane is [07S04]
    1.