Antenna Array MCQ

Test your knowledge with important Antenna Array MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Antenna Array MCQs at Bissoy

• Which of the following is the correct condition of an ordinary end-fire array?
  ক

  β=±kd

  খ

  β=kd

  গ

  β > kd

  ঘ

  β < ±kd
• Find the overall length of an end-fire array with 10 elements and spacing λ/4.
  ক

  \(\frac{9λ}{4}\)

  খ

  \(\frac{5λ}{4}\)

  গ

  \(\frac{5λ}{2}\)

  ঘ

  \(\frac{9λ}{2}\)
• Which of the following statements is true regarding end-fire array?
  ক

  The necessary condition of an ordinary end-fire array is β=±kd+nπ

  খ

  The phase excitation difference is zero

  গ

  Same input current is fed through the array, but the phase excitation is varies progressively

  ঘ

  Maximum radiation occurs at normal to the axis of array
• The phase excitation difference is zero in end-fire array.
  ক

  True

  খ

  False
• The direction of maximum radiation in end-fire array is ______ with respect to the array axis.
  ক

  0° or 180°

  খ

  90°

  গ

  45°

  ঘ

  270°
• In a broadside array all the elements must have equal ______ excitation with similar amplitude excitations to get maximum radiation.
  ক

  Phase

  খ

  Frequency

  গ

  Voltage

  ঘ

  Current
• Which of the following cannot be the separation between elements in a broadside array to avoid grating lobes?
  ক

  4λ/2

  খ

  λ/2

  গ

  3λ/2

  ঘ

  5λ/2
• Which of the following statements is false regarding a broadside array?
  ক

  The maximum radiation is normal to the axis of the array

  খ

  Must have same amplitude excitation but different phase excitation among different elements

  গ

  The spacing between elements must not equal to the integral multiples of λ

  ঘ

  The phase excitation difference must be equal to zero
• In Broadside array the maximum radiation is directed with respected to the array axis at an angle____
  ক

  90°

  খ

  45°

  গ

  0°

  ঘ

  180°
• The isotropic element array radiation pattern depends on the nulls of the array factor only.
  ক

  True

  খ

  False
• Which of the following doesn’t applicable for pattern multiplication?
  ক

  It is the product of the individual radiation pattern of the element with the array factor of the array

  খ

  All elements must be identical

  গ

  All elements need not be identical

  ঘ

  This gives the radiation pattern of the entire array
• All the elements must be identical to apply pattern multiplication principle.
  ক

  True

  খ

  False
• Which of the following expression represents the pattern multiplication?
  ক

  Etotal=Eθ × Array Factor

  খ

  Etotal=Eθ × Directivity

  গ

  Etotal=Eall elements × Array Factor

  ঘ

  Etotal=Eθ × Beamwidth
• Pattern multiplication is the multiplication of single array radiation pattern with ___
  ক

  Array Factor

  খ

  Beamwidth

  গ

  Total Field

  ঘ

  Directivity
• Multiplying the normalized field with the normalized array factor gives ___________
  ক

  pattern multiplication

  খ

  array factor

  গ

  beamwidth

  ঘ

  null
• Which of the following is true for uniform linear array elements, to obtain the total field?
  ক

  The single element field is multiplied by the array factor

  খ

  The single element field is multiplied by the normalized array factor

  গ

  The single element field is multiplied by the beamwidth

  ঘ

  The single element field is multiplied by the directivity
• The radiating pattern of single element multiplied by the array factor simply gives the ___________
  ক

  Pattern multiplication

  খ

  Normalized array factor

  গ

  Beamwidth of the array

  ঘ

  Field strength of the array
• Which of the following statement about antenna array is false?
  ক

  Field pattern is the product of individual elements in array

  খ

  Field pattern is the sum of individual elements in array

  গ

  Resultant field is the vector superposition of the fields from individual elements in array

  ঘ

  High directivity can be achieved for long distance communications
• What is the progressive phase shift of the end-fire array?
  ক

  0

  খ

  90

  গ

  180

  ঘ

  60
• If the progressive shift in antenna array is equal to zero then it is called _________
  ক

  Broad side

  খ

  End-fire

  গ

  Yagi-uda

  ঘ

  Fishbone antenna
• Total resultant field obtained by the antenna array is given by which of following?
  ক

  Vector superposition of individual field from the element

  খ

  Maximum field from individual sources in the array

  গ

  Minimum field from individual sources in the array

  ঘ

  Field from the individual source
• A uniform linear array contains _____________
  ক

  N elements placed at equidistance and fed currents of equal magnitude and progressive phase shift

  খ

  N elements at non-equidistance and fed currents of equal magnitude and progressive phase shift

  গ

  N elements at equidistance and fed currents of unequal magnitude and progressive phase shift

  ঘ

  N elements at equidistance and fed currents of unequal magnitude and equal phase shift
• The electrical size of antenna is increased by antenna array to avoid size lobes compared to single antenna.
  ক

  True

  খ

  False
• Which of the following is false about the single antenna for long distance communication?
  ক

  Enlarging may create side lobes

  খ

  No side lobes

  গ

  High directivity is required

  ঘ

  High Gain is required
• For long distance communication, which of the property is mainly necessary for the antenna?
  ক

  High directivity

  খ

  Low directivity

  গ

  Low gain

  ঘ

  Broad beam width
• Electrical size of antenna is increased by which of the following?
  ক

  Antenna Array

  খ

  Decreasing the coverage area

  গ

  Increasing the coverage area

  ঘ

  Using a single antenna
• Which of the following is false regarding Antenna array?
  ক

  Directivity increases

  খ

  Directivity decreases

  গ

  Beam width decreases

  ঘ

  Gain increases