Deck 3: Antenna Fundamentals and Characteristics

Question 1

What is the beam width for a half wave dipole antenna?

A)90°
B)180°
C)50°
D)250°

Answer 1

90°

Question 2

What does the beam width of an antenna tell us?

A)signal strength
B)signal power
C)directivity
D)degradation

Answer 2

signal strength

Question 3

What is the power radiated by the antenna with gain called as?

A)critical power
B)transverse power
C)effective radiated power
D)transmitted power

Answer 3

effective radiated power

Question 4

What is the radiation pattern of an isotropic radiator?

A)doughnut
B)sphere
C)hemisphere
D)circular

Question 5

What is the impedance of the folded dipole antenna?

A)50?
B)100?
C)300?
D)20?

Question 6

Which of the following antennas produce a vertical radiation pattern?

A)dipole antenna
B)yagi antenna
C)marconi antenna
D)hertz antenna

Question 7

The members of the antenna family which are made of wires of certain value in terms of operating wavelength are called:

A)loop antennas
B)wire antennas
C)dipole antenna
D)slot antennas

Question 8

The antenna in which location of the feed determines the direction of the lobe are:

A)wire antenna
B)loop antenna
C)helical antenna
D)horn antenna

Question 9

Based on the size of the loops, loop antennas are classified as small and large loops. This is the only classification of loop antenna.

Question 10

Antenna that does not belong to the horn antenna family among the following are:

A)pyramidal horn
B)conical horn
C)bi-conical horn
D)none of the mentioned

Question 11

Reflector antennas are widely used to modify radiation patterns of radiating elements.

Question 12

The pattern of the reflector in a reflector antenna is called:

A)primary pattern
B)secondary pattern
C)reflector pattern
D)none of the mentioned

Question 13

__________antennas have gain less than reflector antennas but have more lenient tolerance on surfaces.

A)helical antennas
B)lens antennas
C)array antennas
D)slot antennas

Question 14

Lens antennas are classified into two types. One being fast antenna, the other one is:

A)slow antenna
B)delay antenna
C)dynamic antenna
D)none of the mentioned

Question 15

The antennas which offer high operational bandwidth and the antenna parameters are maintained over a wide range of antennas are called:

A)wide band antennas
B)array antennas
C)parabolic antennas
D)none of the mentioned

Question 16

High directivity required in RADAR communication is satisfied using this type of antennas:

A)wide band antennas
B)antenna arrays
C)slot antennas
D)patch antennas

Question 17

The terminal impedance of a dipole antenna is 710 ?. The terminal impedance of the slot antenna given the intrinsic impedance of air is 377 ? is:

A)100 ?
B)50 ?
C)25 ?
D)none of the mentioned

Question 18

When the separation between two lines that carry the TEM wave approaches ? the wave tends to be radiated.

Question 19

An antenna has a field pattern of E (?) = cos2 ?, ? varies between 0 and 900. Half power beam width of the antenna is:

A)330
B)660
C)12000
D)none of the mentioned

Question 20

Power radiated from an antenna per unit solid angle is called radiation intensity.

Question 21

Antennas are bidirectional devices.

Question 22

Which of the following is false regarding Antenna array?

A)directivity increases
B)directivity decreases
C)beam width decreases
D)gain increases

Question 23

Electrical size of antenna is increased by which of the following?

A)antenna array
B)decreasing the coverage area
C)increasing the coverage area
D)using a single antenna

Question 24

For long distance communication, which of the property is mainly necessary for the antenna?

A)high directivity
B)low directivity
C)low gain
D)broad beam width

Question 25

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

A)enlarging may create side lobes
B)no side lobes
C)high directivity is required
D)high gain is required