# A helical antenna is used for satellite tracking because of its

1.  circular polarization

2.  maneuverability

4.  good front-to-back ratio

4

circular polarization

Explanation :
No Explanation available for this question

# For a dipole antenna

1.  the radiation. Intensity is maximum along the normal to the dipole axis

2.  the current distribution along length is uniform irrespective of the length

3.  the effective length equals. physical length

4.  the input impedance is independent of the location of the feed-point

4

the radiation. Intensity is maximum along the normal to the dipole axis

Explanation :
No Explanation available for this question

# An antenna, when radiating, has a highly directional radiation pattern. When the antenna is receiving, radiation pattern

1.  is more directive

2.  is less directive

3.  is the same

4.  exhibits no directivity at all

4

is the same

Explanation :
No Explanation available for this question

# A transverse electromagnetic wave with circular polarization is received by a dipole antenna. Duo to polarisation mismatch, the power transfer efficiency from the wave to the antena is reduced to about

1.  50%

2.  33.3%

3.  25%

4.  0%

4

50\%

Explanation :
No Explanation available for this question

# A rectangular metal wave guide filled with a dielectric material of relative permittivity r=4 has the inside dimensions 3.0cmx12 cm. The cut-off frequency for the dominant mode is

1.  2.5GHz

2.  5.0GHz

3.  10.GHz

4.  12.5GHz

4

2.5GHz

Explanation :
No Explanation available for this question

# An ideal 10 dB directional coupler is shown in the figure. The power output at port-3 will be

1.  10mW

2.  15mW

3.  20mW

4.  25mW

4

10mW

Explanation :
No Explanation available for this question

# In the reflectometer arrangement shown . the given figure, if the power meters A and B indicate 1mW and 110 microwatts respectively, then the proximate VSWR on the lines will be

1.  1.5

2.  2.0

3.  2.5

4.  3.0

4

2.0

Explanation :
No Explanation available for this question

# A dipole antenna was radiating with some excitation in free space radiating a certain amount of the power. If this antenna . immersed . a lake where water is non-dissipative but has a dielectric constant of 81, the radiated power with the same excitation will

1.  decrease to finite non-zero value

2.  remain the same

3.  increase

4.  decrease to zero

4

decrease to finite non-zero value

Explanation :
No Explanation available for this question

# An antenna has a gain of 44 dB. Assuming that the main beam of the antenna is circular. cross-section, the beam width will be

1.  0.44560

2.  1.44560

3.  2.44560

4.  3.44560

4

2.44560

Explanation :
No Explanation available for this question

1.  146W

2.  73W

3.  36.5W

4.  18.25W

4