Effective radiated power of an isotropic radiator can be given as a product of

receiving power and receiving gain

radiated power and received power

effective area and physical area

transmitted power and transmitting gain

receiving power and receiving gain

Antennaâ€™s efficiency is given by the ratio of

physical aperture to effective aperture

effective aperture to physical aperture

physical aperture to effective aperture

Which is the primary cost for degradation of error performance?

signal distortion & loss in signal to noise ratio

Link budget consists of calculation of

useful signal & interfering noise power

In the expression for phase of the reflection coefficient, Lmin stands for :

distance between load and first voltage maximum

distance between load and first voltage minimum

distance between load and first voltage maximum

distance between consecutive minimas

distance between a minima and immediate maxima

Slotted line is a transmission line configuration that allows the sampling of:

magnetic field amplitude of a standing wave on a terminated line

electric field amplitude of a standing wave on a terminated line

magnetic field amplitude of a standing wave on a terminated line

current that is generated by the source

217 + Mcqs in Antennas And Microwave Engineering in Electrical Engineering Page 4 McqOptions

151.	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
Answer» C. dynamic antenna

Discussion

152.	Â Â Â Â Â Â Â Â Â Â Â Â Â 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
Answer» C. array antennas

Discussion

153.	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
Answer» C. reflector pattern

Discussion

154.	Reflector antennas are widely used to modify radiation patterns of radiating elements.
A.	true
B.	false
Answer» B. false

Discussion

155.	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
Answer» E.

Discussion

156.	Based on the size of the loops, loop antennas are classified as small and large loops. This is the only classification of loop antenna.
A.	true
B.	false
Answer» C.

Discussion

157.	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
Answer» B. loop antenna

Discussion

158.	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
Answer» D. slot antennas

Discussion

159.	Which of the following antennas produce a vertical radiation pattern?
A.	dipole antenna
B.	yagi antenna
C.	marconi antenna
D.	hertz antenna
Answer» D. hertz antenna

Discussion

160.	What is the impedance of the folded dipole antenna?
A.	50Î©
B.	100Î©
C.	300Î©
D.	20Î©
Answer» D. 20Î©

Discussion

161.	What is the radiation pattern of an isotropic radiator?
A.	doughnut
B.	sphere
C.	hemisphere
D.	circular
Answer» C. hemisphere

Discussion

162.	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» D. transmitted power

Discussion

163.	What does the beam width of an antenna tell us?
A.	signal strength
B.	signal power
C.	directivity
D.	degradation
Answer» D. degradation

Discussion

164.	What is the beam width for a half wave dipole antenna?
A.	90Â°
B.	180Â°
C.	50Â°
D.	250Â°
Answer» B. 180Â°

Discussion

165.	The radiation pattern of a half-wave dipole has the shape of a
A.	doughnut
B.	sphere
C.	hemisphere
D.	circular
Answer» B. sphere

Discussion

166.	The type of dipole antenna that has a higher band width is called as?
A.	conical antenna
B.	yagi antenna
C.	helical antenna
D.	marconi antenna
Answer» B. yagi antenna

Discussion

167.	What happens when the radiation resistance of the antenna matches the characteristic impedance of the transmission line?
A.	no transmission occurs
B.	no reception occurs
C.	swr is maximum
D.	swr is minimum
Answer» E.

Discussion

168.	The impedance at the center of the antenna is known as?
A.	characteristic impedance
B.	radiation resistance
C.	transmission impedance
D.	recovery resistance
Answer» C. transmission impedance

Discussion

169.	A dipole antenna is also called as?
A.	marconi antenna
B.	yagi antenna
C.	bidirectional antenna
D.	hertz antenna
Answer» E.

Discussion

170.	Effective radiated power of an isotropic radiator can be given as a product of
A.	radiated power and received power
B.	effective area and physical area
C.	transmitted power and transmitting gain
D.	receiving power and receiving gain
Answer» D. receiving power and receiving gain

Discussion

171.	Antennaâ€™s efficiency is given by the ratio of
A.	effective aperture to physical aperture
B.	physical aperture to effective aperture
C.	signal power to noise power
D.	losses
Answer» B. physical aperture to effective aperture

Discussion

172.	Space loss occurs due to a decrease in
A.	electric field strength
B.	efficiency
C.	phase
D.	signal power
Answer» B. efficiency

Discussion

173.	Mechanism contributing to a reduction in efficiency is called as
A.	amplitude tapering
B.	blockage
C.	edge diffraction
D.	all of the mentioned
Answer» E.

Discussion

174.	Antennas are used
A.	as transducer
B.	to focus
C.	as transducer & to focus
D.	none of the mentioned
Answer» D. none of the mentioned

Discussion

175.	Which factor adds phase noise to the signal?
A.	jitter
B.	phase fluctuations
C.	jitter & phase fluctuations
D.	none of the mentioned
Answer» D. none of the mentioned

Discussion

176.	Which is the primary cost for degradation of error performance?
A.	loss in signal to noise ratio
B.	signal distortion
C.	signal distortion & loss in signal to noise ratio
D.	none of the mentioned
Answer» D. none of the mentioned

Discussion

177.	Link budget consists of calculation of
A.	useful signal power
B.	interfering noise power
C.	useful signal & interfering noise power
D.	none of the mentioned
Answer» D. none of the mentioned

Discussion

178.	If the reflection coefficient of a transmission line is 0.4, then the standing wave ratio is:
A.	1.3333
B.	2.3333
C.	0.4
D.	0.6
Answer» C. 0.4

Discussion

179.	If the normalized load impedance of a transmission line is 2, then the reflection co- efficient is:
A.	0.33334
B.	1.33334
C.	1
Answer» B. 1.33334

Discussion

180.	In the expression for phase of the reflection coefficient, Lmin stands for :
A.	distance between load and first voltage minimum
B.	distance between load and first voltage maximum
C.	distance between consecutive minimas
D.	distance between a minima and immediate maxima
Answer» B. distance between load and first voltage maximum

Discussion

181.	If the standing wave ratio for a transmission line is 1.4, then the reflection coefficient for the line is:
A.	0.16667
B.	1.6667
C.	0.01667
D.	0.96
Answer» B. 1.6667

Discussion

182.	A modern device that replaces a slotted line is:
A.	digital cro
B.	generators
C.	network analyzers
D.	computers
Answer» D. computers

Discussion

183.	Slotted line is a transmission line configuration that allows the sampling of:
A.	electric field amplitude of a standing wave on a terminated line
B.	magnetic field amplitude of a standing wave on a terminated line
C.	voltage used for excitation
D.	current that is generated by the source
Answer» B. magnetic field amplitude of a standing wave on a terminated line

Discussion

184.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â has a constant power spectral density.
A.	white noise
B.	gaussian noise
C.	thermal noise
D.	shot noise
Answer» B. gaussian noise

Discussion

185.	A resistor is operated at a temperature of 300 K, with a system bandwidth of 1 MHz then the noise power produced by the resistor is:
A.	3.13Ã—10-23 watts
B.	4.14Ã—10-15 watts
C.	6.14Ã—10-15 watts
D.	none of the mentioned
Answer» C. 6.14Ã—10-15 watts

Discussion

186.	Low is the G/T ratio of an antenna, higher is its efficiency.
A.	true
B.	false
Answer» C.

Discussion

187.	The noise temperature of an antenna is given by the expression:
A.	radtb + (1-rad) tp
B.	(1-rad) tp
C.	radtb
D.	none of the mentioned
Answer» B. (1-rad) tp

Discussion

188.	With an increase in operating frequency, the background noise temperature:
A.	increases
B.	decreases
C.	remains constant
D.	remains unaffected
Answer» B. decreases

Discussion

189.	Gain of an antenna is always greater than the directivity of the antenna.
A.	true
B.	false
Answer» C.

Discussion

190.	A rectangular horn antenna has an aperture area of 3Î» Ã— 2Î». Then the maximum directivity that can be achieved by this rectangular horn antenna is:
A.	24 db
B.	4 db
C.	19 db
D.	insufficient data
Answer» D. insufficient data

Discussion

191.	A rectangular horn antenna has an aperture area of 3Î» Ã— 2Î». If the aperture efficiency of an antenna is 90%, then the directivity of the antenna is:
A.	19 db
B.	17.1 db
C.	13 db
D.	21.1 db
Answer» C. 13 db

Discussion

192.	If the power input to an antenna is 100 mW and if the radiated power is measured to be 90 mW, then the efficiency of the antenna is:
A.	75 %
B.	80 %
C.	90 %
D.	insufficient data
Answer» D. insufficient data

Discussion

193.	If an antenna has a directivity of 16 and radiation efficiency of 0.9, then the gain of the antenna is:
A.	16.2
B.	14.8
C.	12.5
D.	19.3
Answer» B. 14.8

Discussion

194.	If the beam width of an antenna in two orthogonal planes are 300 and 600. Then the directivity of the antenna is:
A.	24
B.	18
C.	36
D.	12
Answer» C. 36

Discussion

195.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â of an antenna is a plot of the magnitude of the far field strength versus position around the antenna.
A.	radiation pattern
B.	directivity
C.	beam width
D.	none of the mentioned
Answer» B. directivity

Discussion

196.	Beamwidth and directivity are both measures of the focusing ability of an antenna.
A.	true
B.	false
Answer» B. false

Discussion

197.	Antennas having a constant pattern in the azimuthal plane are called
A.	high gain antenna
B.	omni directional antenna
C.	unidirectional antenna
D.	low gain antenna
Answer» C. unidirectional antenna

Discussion

198.	Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â antennas consist of a regular arrangement of antenna elements with a feed network
A.	aperture antennas
B.	array antennas
C.	printed antennas
D.	wire antennas
Answer» C. printed antennas

Discussion

199.	Power radiated from an antenna per unit solid angle is called radiation intensity.
A.	true
B.	false
Answer» B. false

Discussion

200.	A Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â is a device that converts a guided electromagnetic wave on a transmission line into a plane wave propagating in free space.
A.	transmitting antenna
B.	receiving antenna
C.	radar
D.	mixer
Answer» B. receiving antenna

Discussion

Explore topic-wise MCQs in Electrical Engineering.

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

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

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

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

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

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

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

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

Which of the following antennas produce a vertical radiation pattern?

What is the impedance of the folded dipole antenna?

What is the radiation pattern of an isotropic radiator?

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

What does the beam width of an antenna tell us?

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

The radiation pattern of a half-wave dipole has the shape of a

The type of dipole antenna that has a higher band width is called as?

What happens when the radiation resistance of the antenna matches the characteristic impedance of the transmission line?

The impedance at the center of the antenna is known as?

A dipole antenna is also called as?

Effective radiated power of an isotropic radiator can be given as a product of

Antennaâ€™s efficiency is given by the ratio of

Space loss occurs due to a decrease in

Mechanism contributing to a reduction in efficiency is called as

Antennas are used

Which factor adds phase noise to the signal?

Which is the primary cost for degradation of error performance?

Link budget consists of calculation of

If the reflection coefficient of a transmission line is 0.4, then the standing wave ratio is:

If the normalized load impedance of a transmission line is 2, then the reflection co- efficient is:

In the expression for phase of the reflection coefficient, Lmin stands for :

If the standing wave ratio for a transmission line is 1.4, then the reflection coefficient for the line is:

A modern device that replaces a slotted line is:

Slotted line is a transmission line configuration that allows the sampling of:

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â has a constant power spectral density.

A resistor is operated at a temperature of 300 K, with a system bandwidth of 1 MHz then the noise power produced by the resistor is:

Low is the G/T ratio of an antenna, higher is its efficiency.

The noise temperature of an antenna is given by the expression:

With an increase in operating frequency, the background noise temperature:

Gain of an antenna is always greater than the directivity of the antenna.

A rectangular horn antenna has an aperture area of 3Î» Ã— 2Î». Then the maximum directivity that can be achieved by this rectangular horn antenna is:

A rectangular horn antenna has an aperture area of 3Î» Ã— 2Î». If the aperture efficiency of an antenna is 90%, then the directivity of the antenna is:

If the power input to an antenna is 100 mW and if the radiated power is measured to be 90 mW, then the efficiency of the antenna is:

If an antenna has a directivity of 16 and radiation efficiency of 0.9, then the gain of the antenna is:

If the beam width of an antenna in two orthogonal planes are 300 and 600. Then the directivity of the antenna is:

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â of an antenna is a plot of the magnitude of the far field strength versus position around the antenna.

Beamwidth and directivity are both measures of the focusing ability of an antenna.

Antennas having a constant pattern in the azimuthal plane are called

Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â antennas consist of a regular arrangement of antenna elements with a feed network

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

A Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â is a device that converts a guided electromagnetic wave on a transmission line into a plane wave propagating in free space.