Antenna MCQs

Question 1

The maximum effective aperture of a microwave antenna which has a directivity of 900, wil be

Accepted Answer

71.619 X2

Answer

716.19X2

Answer

7161.9 X2

Answer

71619 X2

Question 2

The gain of an antenna with a circular aperture of diameter 3 metres at a frequency of 5 GHz, will be

Accepted Answer

24674

Answer

2.4674

Answer

24.674

Answer

246.74

Question 3

The radiation resistance of a ?16 wire dipole in free space will be nearly

Accepted Answer

3 n

Answer

1 SI

Answer

13 SZ

Answer

30 SI

Question 4

The total field produced by an antenna array system at a great distance from it is

Accepted Answer

vector sum of the fields produced by the individual antennas of the array system.

Answer

sum of the fields produced by the individual antennas of the array system

Answer

directional gain of antenna

Answer

linear antenna gain

Question 5

A broad side array is shown in Fig. 13.4 in which the elements are placed at equal distancdes. The direction of maximum radiation is represented by

Accepted Answer

AA

Answer

BB

Answer

CC

Answer

DD

Question 6

The radiation pattern of two element collinear array is represented in

Accepted Answer

figure A

Answer

figure B

Answer

figure C

Answer

figure D

Question 7

In binomial arrays the elimination of secondary lobes takes place

Accepted Answer

at the cost of directivity

Answer

at the cost of gain

Answer

both (a) and (b) above

Answer

none of the above

Question 8

The transmitting antennas for lower frequencies (below 500 kHz) are generally

Accepted Answer

vertically grounded wire type

Answer

horizontal suspended wire type

Answer

parabolic reflector type

Answer

any of the above

Question 9

In Fig. 13.6 the voltage distribution on a vertical earthed antenna is represened by

Accepted Answer

curve B

Answer

curve A

Answer

curve C

Answer

curve D