Deck 14: Antennas

Question 1

What is the loop antenna's major application?
A.Good gain over extremely wide range of frequencies
B.Broadcast AM receivers
C.Receiving antenna for broadcast FM
D.Direction finding

Answer 1

Direction finding

Question 2

The monopole antenna is used primarily with frequencies below __________.
A.2 MHz
B.100 MHz
C.50 MHz
D.55 MHz

Answer 2

2 MHz

Question 3

An antenna with a purely resistive impedance exhibits what condition?
A.Resistance
B.Distance
C.Resonance
D.Capacitance

Answer 3

R esonance

Question 4

What does the height of the antenna above ground affect?
A.Radiation resistance
B.Radiation pattern
C.Radiation loss
D.Radiation fields

Question 5

___________ is the angular separation between the half-power points on an antenna's radiation pattern.
A.Bandwidth
B.Gain
C.Beamwidth
D.Resonance

Question 6

What type of antenna is typically built right into the wings of aircraft?
A.Folded dipole
B.Slot
C.Phased array
D.Ferrite loop

Question 7

What type of communication is generally of a point-to-point nature?
A.Terrestrial
B.Microwave
C.Satellite
D.Voice-grade

Question 8

Because microwave communications are line of sight,what must be made to ensure that no obstructions lie anywhere in the line between transmitter and receiver?
A.Yagi-Uda configuration
B.Polar pattern
C.Path study
D.Link-budget analysis

Question 9

What does the most basic form of an antenna consist of?
A.Single conductor
B.Electric field
C.Reflector
D.Amplifier

Question 10

An antenna is a transducer that converts energy from electrical form to _____________ form and vice versa.
A.magnetic
B.electromagnetic
C.radiated
D.polarized

Question 11

What is the name of the portion of field energy that does collapse back into the antenna and is limited to the zone immediately surrounding the antenna?
A.Radiation
B.Far
C.Near
D.Induction

Question 12

What results when the gain of an antenna is multiplied by its power input?
A.Effective radiated power
B.Effective isotropic radiated power
C.Received power
D.Transmitter output power

Question 13

Antenna gain is always expressed in terms of the ______________________.
A.angular separation between the half-power points on its radiation pattern
B.direction of maximum radiation
C.presence of reactive components
D.charge lines developing around the antenna

Question 14

All radio systems must be designed to be resistant to fading. What is one of the biggest factors that would cause reductions in signal strength?
A.Antenna size
B.Weather
C.Noise
D.Dry heat

Question 15

The property of interchangeability for transmitting and receiving operations is antenna ____________.
A.polarization
B.frequency
C.reciprocity
D.impedance

Question 16

There are three basic forms of horn antennas: sectoral,circular,and ______________.
A.pyramidal
B.horizontal
C.vertical
D.symmetrical

Question 17

___________ represent a cross-sectional view and attempt to show the three-dimensional radiation pattern in two dimensions.
A.Longley-Rice models
B.Polar plots
C.Path studies
D.Fade margins

Question 18

The key reasons for the popularity of a parabolic reflector are its high gain and ___________.
A.directivity
B.simplicity
C.low cost
D.bandwidth

Question 19

Dish antennas are capable of very high signal gains by focusing energy onto a very narrow ___________.
A.beamwidth
B.bandwidth
C.current
D.transmission line

Question 20

What is one advantage of connecting a resonant transmission line to an antenna?
A.It decreases power losses.
B.Its electrical length corresponds closely to its physical length.
C.It is an effective resistance related to the power radiated by the antenna.
D.It makes impedance matching unnecessary.

Question 21

What type of antenna is found in repeater installations for two-way radio applications?
A.Phased array
B.Yagi-Uda
C.Broadside array
D.Collinear

Question 22

Which of the following terms defines the orientation of the electric field,which is the same as the antenna's physical configuration?
A.Reciprocity
B.Beamwidth
C.Resonance
D.Polarization

Question 23

Which of the following consists of a structure made of wire erected a short distance above the ground and insulated from the ground?
A.Loading coil
B.Counterpoise
C.Feed line
D.Transducer

Question 24

Antenna bandwidth is defined with respect to its design _____________.
A.frequency
B.components
C.complexity
D.directivity

Question 25

An antenna array is one that has more than one element or component. What is the name of the array if one or more of the elements is not electrically connected?
A.Parasitic
B.Driven
C.Collinear
D.Broadside