Antennas Practice Test 4

1. What is the ratio of focal length to diameter for practical applications in a parabolic reflector?

< 0.25

0.125 to 0.3

0.5 to 1

0.25 to 0.5

2. Which of the following efficiency is used to measure the power-loss at the feed pattern which is intercepted by reflector?

Taper

Spillover

Aperture

Illumination

3. Which of the following is not a reflector antenna?

Convex-convex

Gregorian

Corner

Cassegrain

4. Which of the following refers to the pattern of reflector in the reflector antenna?

Reflector pattern

Secondary pattern

Primary pattern

Feed pattern

5. Find the optimum aperture angle for H-plane horn with aperture 12λ and path travel difference 0.4λ?

7.59°

1.59°

15.18°

75.9°

6. Which of the following is used to produce wide beam in one plane and narrow beam in other plane?

Pill box

Paraboloid with rectangular aperture

Cassegrain

Truncated paraboloid

7. Which of the following is false regarding a reflector antenna?

Reflector antennas are high gain antennas with two antennas

The pattern of the reflector in the reflector antenna is the Secondary pattern

Both the primary and secondary antennas are excited

A dual reflector contains two reflectors and one primary feed

8. In order to achieve good system efficiency in a corner reflector, the spacing between the vertex and the feed must be ______ as included angle decreases.

Either increases or decreases

Decreased

Constant

Increased

9. Which of the following antenna has the parallel slots along the inside surface of the horn?

Pyramidal horn

Corrugated horn

Exponential horn

E-plane horn

10. When a reflector is placed at the foci along the feed it is called ____ antenna

Convex-Convex

Dual reflector antenna

Plane antenna

Wire antenna