Antenna and Wave Propagation 4

Lets Crack Online Exam

Electronic Engineering MCQ Question Papers: ENTC, IT Interview Placement

Subject: Antenna and Wave Propagation 4

Part 4: List for questions and answers of Antenna & wave Propagation


Q1. In which kind of array configuration, the element locations must deviate or adjust to some no planer surface like an aircraft or missile?

a) Linear

b) Planer

c) Conformal

d) All of the above


Q2. According to the directivity of a small loop, which value of θ  contributes to achieve the maximum value of radiation intensity (Umax)?

a) 0°

b) 90°

c) 180°

d) 270°


Q3. From the radiation point of view, small loops are _________radiators

a) Poor

b) Good

c) Better

d) Excellent


Q4. In electrically small loops, the overall length of the loop is ______ one-tenth of a wavelength

a) Less than

b) Equal to

c) Greater than

d) None of the above


Q5. Which pattern is generated due to plotting of square of amplitude of an electric field?

a) Field Pattern

b) Voltage Pattern

c) Power Pattern

d) All of the above


Q6. In flared transmission line, the radiation phenomenon increases due to ________ in flaring

a) Increase

b) Decrease

c) Stability

d) None of the above 


Q7. How are the infinitesimal dipoles represented in terms of antenna length and signal wavelength?

a) l less than & equal to (λ  /50)

b) (λ /50 ) less than l less than & equal to (λ /10)

c) l = λ /2

d) None of the above


Q8. Which waveform plays a crucial role in determining the radiation pattern of the dipole/wire antennas?

a) Current

b) Voltage

c) Frequency

d) Phase


Q9. Which operations are performed by vector potentials (A, F) over the radiated fields (E & H)?

a) Addition

b) Subtraction

c) Differentiation

d) Integration


Q10. Which auxiliary functions assist in solving the radiation problem by evaluation of E & H using sources J & M?

a) Scalar potentials

b) Vector potentials

c) Gradient potentials

d) Divergence potentials


Q11. If an observation point is closely located to the source, then the field is termed as ________

a) Induced

b) Radiated

c) Reflected

d) Far-field


Q12. Which among the following defines the angular distance between two points on each side of major lobe especially when the radiation drops to zero?

a) Half power beam width (HPBW)

b) First null beam width (FNBW)

c) Side lobe level (SLL)

d) Front to back ratio (FBR) 


Q13. At which angles does the front to back ratio specify an antenna gain?

a) 0° & 180°

b) 90° & 180°

c) 180° & 270°

d) 180° & 360°


Q14. The knowledge of which parameter is sufficient for deriving the time varying electromagnetic field?

a) Electric field intensity

b) Magnetic field intensity

c) Current density

d) Power density


Q15. In a non-isotropic directional antenna, which radiating lobe axis makes an angle of 180° w.r.t. major beam of an antenna?

a) Minor lobe

b) Side lobe

c) Back lobe

d) None of the above


Q16. Under which conditions of charge does the radiation occur through wire antenna?

a) For a charge with no motion

b) For a charge moving with uniform velocity with straight & infinite wire

c) For a charge oscillating in time motion

d) All of the above


Q17. According to Webster’s dictionary, what is an antenna?

a) Impedance matching device

b) Sensor of electromagnetic waves

c) Transducer between guided wave & free space wavec

d) Metallic device for radiating or receiving radio waves


Q18. F2 layer of appleton region acts as a significant reflecting medium for _____ frequency radio waves

a) Low

b) Moderate

c) High

d) All of the above 


Q19. Which layer has the atmospheric conditions exactly opposite to that of standard atmosphere?

a) Depression layer

b) Regression layer

c) Inversion layer

d) Invasion layer


Q20. On which factor/s do/does the radiation field of a small loop depend?

a) Shape

b) Area

c) Both a and b

d) None of the above 



Part 4: List for questions and answers of Antenna & wave Propagation


Q1. Answer: c


Q2. Answer: b


Q3. Answer: a


Q4. Answer: a


Q5. Answer: c


Q6. Answer: a


Q7. Answer: a


Q8. Answer: a


Q9. Answer: c


Q10. Answer: b


Q11. Answer: a


Q12. Answer: b


Q13. Answer: a


Q14. Answer: c


Q15. Answer: c


Q16. Answer: c


Q17. Answer: d


Q18. Answer: c


Q19. Answer: c


Q20. Answer: b