430+ Broadband Communication Systems Solved MCQs

These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: Electronics and Telecommunication Engineering [ENTC] .

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201.	The ratio r = (n1 – n)/ (n1 – n) indicates
A.	fresnel reflection
B.	reflection coefficient
C.	refraction coefficient
D.	angular power distribution coefficient
Answer» B. reflection coefficient

discuss

202.	A GaAs optical source having a refractive index of 3.2 is coupled to a silica fiber having a refractive index of 1.42. Determine Fresnel reflection at interface in terms of percentage.
A.	13.4%
B.	17.4%
C.	17.6%
D.	14.8%
Answer» D. 14.8%

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203.	A particular GaAs fiber has a Fresnel reflection magnitude of 17.6% i.e. 0.176. Find the power loss between the source and the fiber?
A.	0.86 db
B.	0.78 db
C.	0.84 db
D.	0.83 db
Answer» C. 0.84 db

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204.	Two joined step index fibers are perfectly aligned. What is the coupling loss of numerical aperture are NAR= 0.26 for emitting fiber?
A.	-0.828 db
B.	-0.010 db
C.	-0.32 db
D.	0.32 db
Answer» B. -0.010 db

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205.	Two joined graded index fibers that are perfectly aligned have refractive indices αR=1.93for receiving fiber αE= 2.15 for emitting fiber. Calculate the coupling loss
A.	0.23 db
B.	0.16 db
C.	0.82 db
D.	0.76 db
Answer» A. 0.23 db

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206.	How many types of misalignments occur when joining compatible fiber?
A.	one
B.	two
C.	five
D.	three
Answer» D. three

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207.	Losses caused by factors such as core-cladding diameter, numerical aperture, relative refractive index differences, different refractive index profiles, fiber faults are known as
A.	intrinsic joint losses
B.	extrinsic losses
C.	insertion losses
D.	coupling losses
Answer» A. intrinsic joint losses

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208.	A step index fiber has a coupling efficiency of 0.906 with uniform illumination of all propagation modes. Find the insertion loss due to lateral misalignment?
A.	0.95 db
B.	0.40 db
C.	0.42 db
D.	0.62 db
Answer» C. 0.42 db

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209.	A graded index fiber has a parabolic refractive index profile (α=2) and core diameter of 42μm. Estimate an insertion loss due to a 2 μm lateral misalignment when there is index matching and assuming there is uniform illumination of all guided modes only.
A.	0.180
B.	0.106
C.	0.280
D.	0.080
Answer» D. 0.080

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210.	Determine coupling efficiency if the misalignment loss in a graded index fiber is 0.102
A.	0.136
B.	0.898
C.	0.982
D.	0.684
Answer» B. 0.898

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211.	In a single mode fiber, the losses due to lateral offset and angular misalignment are given by 0.20 dB and 0.46 dB respectively. Find the total insertion loss
A.	0.66 db
B.	0.26 db
C.	0.38 db
D.	0.40 db
Answer» A. 0.66 db

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212.	The intrinsic loss through a multimode fiber joint is independent of direction of propagation. State whether the given statement is true or false
A.	true
B.	false
Answer» B. false

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213.	The expanded beam connectors use ____________ for beam expansion and reduction.
A.	square micro-lens
B.	oval micro-lens
C.	spherical micro-lens
D.	rectangular micro-lens
Answer» C. spherical micro-lens

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214.	Lens-coupled expanded beam connectors exhibit average losses of _________ in case of single mode and graded index fibers.
A.	0.3 db
B.	0.7 db
C.	0.2 db
D.	1.5 db
Answer» B. 0.7 db

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215.	Sapphire ball lens expanded beam design is successful than spherical lens coupled design. State whether the given statement is true or false.
A.	true
B.	false
Answer» A. true

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216.	The fiber is positioned at the ________ of the lens in order to obtain a collimated beam and to minimize lens-to-lens longitudinal misalignment effects.
A.	aperture
B.	focal length
C.	curve
D.	exterior circumference
Answer» B. focal length

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217.	___________ exhibits a parabolic refractive index profile with a maximum at the axis similar to graded index fiber.
A.	lens coupled design
B.	sapphire ball lens
C.	spherical micro-lens
D.	grin-rod lens
Answer» D. grin-rod lens

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218.	The GRIN-rod lens can produce a collimated output beam with a divergent angle αof between _____________ from a light source situated on, or near to, the opposite lens face.
A.	1 to 5 degrees
B.	9 to 16 degrees
C.	4 to 8 degrees
D.	25 to 50 degrees
Answer» A. 1 to 5 degrees

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219.	In the given equation, if r is the radial distance, n is the refractive index; what does z stands for?
A.	focal length
B.	distance along the optical axis
C.	axial angle
D.	diameter
Answer» B. distance along the optical axis

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220.	The majority of the GRIN-rod lenses have diameters in the range of ____________
A.	2 to 2.5 mm
B.	3 to 4 mm
C.	0.1 to 0.4 mm
D.	0.5 to 2 mm
Answer» D. 0.5 to 2 mm

discuss

221.	Which of the following factors does not cause divergence of the collimated beam from a GRIN-rod lens?
A.	lens cut length
B.	size of fiber core
C.	refractive index profile
D.	chromatic aberration
Answer» C. refractive index profile

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222.	GRIN-rod lens connectors have loss characteristics which are independent of the modal power distribution in the fiber. State whether the given statement is true or false.
A.	true
B.	false
Answer» A. true

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223.	A permanent joint formed between two different optical fibers in the field is known as a
A.	fiber splice
B.	fiber connector
C.	fiber attenuator
D.	fiber dispersion
Answer» A. fiber splice

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224.	How many types of fiber splices are available?
A.	one
B.	two
C.	three
D.	four
Answer» B. two

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225.	The insertion losses of the fiber splices are much less than the Fresnel reflection loss at a butted fiber joint. State whether the given statement is true or false.
A.	true
B.	false
Answer» A. true

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226.	What is the main requirement with the fibers that are intended for splicing?
A.	smooth and oval end faces
B.	smooth and square end faces
C.	rough edge faces
D.	large core diameter
Answer» B. smooth and square end faces

discuss

227.	In score and break process, which of the following is not used as a cutting tool?
A.	diamond
B.	sapphire
C.	tungsten carbide
D.	copper
Answer» D. copper

discuss

228.	The heating of the two prepared fiber ends to their fusing point with the application of required axial pressure between the two optical fibers is called as
A.	mechanical splicing
B.	fusion splicing
C.	melting
D.	diffusion
Answer» B. fusion splicing

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229.	Which of the following is not used as a flame heating source in fusion splicing?
A.	microprocessor torches
B.	ox hydric burners
C.	electric arc
D.	gas burner
Answer» D. gas burner

discuss

230.	Average insertion losses as low as _________ have been obtained with multimode graded index and single-mode fibers using ceramic capillaries.
A.	0.1 db
B.	0.5 db
C.	0.02 db
D.	0.3 db
Answer» A. 0.1 db

discuss

231.	_____________ are formed by sandwiching the butted fiber ends between a V-groove glass substrate and a flat glass retainer plate.
A.	springroove splices
B.	v-groove splices
C.	elastic splices
D.	fusion splices
Answer» B. v-groove splices

discuss

232.	Mean splice insertion losses of 0.05 dB are obtained using multimode graded index fibers with the Springroove splice. State whether the given statement is true or false.
A.	true
B.	false
Answer» A. true

discuss

233.	Alignment accuracy of the order ___________ is obtained using the three glass rod alignment sleeve.
A.	0.23 μm
B.	0.15 μm
C.	0.05 μm
D.	0.01 μm
Answer» C. 0.05 μm

discuss

234.	In case of multiple fusion, splice losses using an electric arc fusion device with multimode graded index fiber range from
A.	0.01 to 0.04 db
B.	0.19 to 0.25 db
C.	0.12 to 0.15 db
D.	0.04 to 0.12 db
Answer» D. 0.04 to 0.12 db

discuss

235.	The heating of the two prepared fiber ends to their fusing point with the application of required axial pressure between the two optical fibers is called as
A.	mechanical splicing
B.	fusion splicing
C.	melting
D.	diffusion
Answer» B. fusion splicing

discuss

236.	The rounding of the fiber ends with a low energy discharge before pressing the fibers together and fusing with a stronger arc is called as
A.	pre-fusion
B.	diffusion
C.	crystallization
D.	alignment
Answer» A. pre-fusion

discuss

237.	_____________ is caused by surface tension effects between the two fiber ends during fusing.
A.	pre-fusion
B.	diffusion
C.	self-alignment
D.	splicing
Answer» C. self-alignment

discuss

238.	Mean splice insertion losses of 0.05 dB are obtained using multimode graded index fibers with the Springroove splice. State whether the given statement is true or false.
A.	true
B.	false
Answer» A. true

discuss

239.	When considering source-to-fiber coupling efficiencies, the ________ is an important parameter than total output power.
A.	numerical aperture
B.	radiance of an optical source
C.	coupling efficiency
D.	angular power distribution
Answer» B. radiance of an optical source

discuss

240.	It is a device that distributes light from a main fiber into one or more branch fibers.
A.	optical fiber coupler
B.	optical fiber splice
C.	optical fiber connector
D.	optical isolator
Answer» A. optical fiber coupler

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241.	Optical fiber couplers are also called as ________________
A.	isolators
B.	circulators
C.	directional couplers
D.	attenuators
Answer» C. directional couplers

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242.	How many types of multiport optical fiber couplers are available at present?
A.	two
B.	one
C.	four
D.	three
Answer» D. three

discuss

243.	The optical power coupled from one fiber to another is limited by
A.	numerical apertures of fibers
B.	varying refractive index of fibers
C.	angular power distribution at source
D.	number of modes propagating in each fiber
Answer» D. number of modes propagating in each fiber

discuss

244.	________ couplers combine the different wavelength optical signal onto the fiber or separate the different wavelength optical signal output from the fiber.
A.	3-port
B.	2*2-star
C.	wdm
D.	directional
Answer» C. wdm

discuss

245.	How many fabrication techniques are used for 3 port fiber couplers?
A.	one
B.	two
C.	three
D.	four
Answer» B. two

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246.	The most common method for manufacturing couplers is ____________
A.	wavelength division multiplexing
B.	lateral offset method
C.	semitransparent mirror method
D.	fused bi-conical taper (fbt) technique
Answer» D. fused bi-conical taper (fbt) technique

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247.	Couplers insertion loss is same as that of excess loss. State whether the given statement is true or false.
A.	true
B.	false
Answer» B. false

discuss

248.	A four-port multimode fiber FBT coupler has 50 μWoptical power launched into port 1. The measured output power at ports 2,3 and 4 are 0.003, 23.0 and 24.5 μW respectively. Determine the excess loss.
A.	0.22 db
B.	0.33 db
C.	0.45 db
D.	0.12 db
Answer» A. 0.22 db

discuss

249.	A four-port FBT coupler has 60μW optical power launched into port one. The output powers at ports 2, 3, 4 are 0.0025, 18, and 22 μW respectively. Find the split ratio?
A.	42%
B.	46%
C.	52%
D.	45%
Answer» D. 45%

discuss

250.	How many manufacturing methods are used for producing multimode fiber star couplers?
A.	two
B.	one
C.	three
D.	five
Answer» A. two

discuss

430+ Broadband Communication Systems Solved MCQs

The ratio r = (n1 – n)/ (n1 – n) indicates

A GaAs optical source having a refractive index of 3.2 is coupled to a silica fiber having a refractive index of 1.42. Determine Fresnel reflection at interface in terms of percentage.

A particular GaAs fiber has a Fresnel reflection magnitude of 17.6% i.e. 0.176. Find the power loss between the source and the fiber?

Two joined step index fibers are perfectly aligned. What is the coupling loss of numerical aperture are NAR= 0.26 for emitting fiber?

Two joined graded index fibers that are perfectly aligned have refractive indices αR=1.93for receiving fiber αE= 2.15 for emitting fiber. Calculate the coupling loss

How many types of misalignments occur when joining compatible fiber?

Losses caused by factors such as core-cladding diameter, numerical aperture, relative refractive index differences, different refractive index profiles, fiber faults are known as

A step index fiber has a coupling efficiency of 0.906 with uniform illumination of all propagation modes. Find the insertion loss due to lateral misalignment?

A graded index fiber has a parabolic refractive index profile (α=2) and core diameter of 42μm. Estimate an insertion loss due to a 2 μm lateral misalignment when there is index matching and assuming there is uniform illumination of all guided modes only.

Determine coupling efficiency if the misalignment loss in a graded index fiber is 0.102

In a single mode fiber, the losses due to lateral offset and angular misalignment are given by 0.20 dB and 0.46 dB respectively. Find the total insertion loss

The intrinsic loss through a multimode fiber joint is independent of direction of propagation. State whether the given statement is true or false

The expanded beam connectors use ____________ for beam expansion and reduction.

Lens-coupled expanded beam connectors exhibit average losses of _________ in case of single mode and graded index fibers.

Sapphire ball lens expanded beam design is successful than spherical lens coupled design. State whether the given statement is true or false.

The fiber is positioned at the ________ of the lens in order to obtain a collimated beam and to minimize lens-to-lens longitudinal misalignment effects.

___________ exhibits a parabolic refractive index profile with a maximum at the axis similar to graded index fiber.

The GRIN-rod lens can produce a collimated output beam with a divergent angle αof between _____________ from a light source situated on, or near to, the opposite lens face.

In the given equation, if r is the radial distance, n is the refractive index; what does z stands for?

The majority of the GRIN-rod lenses have diameters in the range of ____________

Which of the following factors does not cause divergence of the collimated beam from a GRIN-rod lens?

GRIN-rod lens connectors have loss characteristics which are independent of the modal power distribution in the fiber. State whether the given statement is true or false.

A permanent joint formed between two different optical fibers in the field is known as a

How many types of fiber splices are available?

The insertion losses of the fiber splices are much less than the Fresnel reflection loss at a butted fiber joint. State whether the given statement is true or false.

What is the main requirement with the fibers that are intended for splicing?

In score and break process, which of the following is not used as a cutting tool?

The heating of the two prepared fiber ends to their fusing point with the application of required axial pressure between the two optical fibers is called as

Which of the following is not used as a flame heating source in fusion splicing?

Average insertion losses as low as _________ have been obtained with multimode graded index and single-mode fibers using ceramic capillaries.

_____________ are formed by sandwiching the butted fiber ends between a V-groove glass substrate and a flat glass retainer plate.

Mean splice insertion losses of 0.05 dB are obtained using multimode graded index fibers with the Springroove splice. State whether the given statement is true or false.

Alignment accuracy of the order ___________ is obtained using the three glass rod alignment sleeve.

In case of multiple fusion, splice losses using an electric arc fusion device with multimode graded index fiber range from

The heating of the two prepared fiber ends to their fusing point with the application of required axial pressure between the two optical fibers is called as

The rounding of the fiber ends with a low energy discharge before pressing the fibers together and fusing with a stronger arc is called as

_____________ is caused by surface tension effects between the two fiber ends during fusing.

Mean splice insertion losses of 0.05 dB are obtained using multimode graded index fibers with the Springroove splice. State whether the given statement is true or false.

When considering source-to-fiber coupling efficiencies, the ________ is an important parameter than total output power.

It is a device that distributes light from a main fiber into one or more branch fibers.

Optical fiber couplers are also called as ________________

How many types of multiport optical fiber couplers are available at present?

The optical power coupled from one fiber to another is limited by

________ couplers combine the different wavelength optical signal onto the fiber or separate the different wavelength optical signal output from the fiber.

How many fabrication techniques are used for 3 port fiber couplers?

The most common method for manufacturing couplers is ____________

Couplers insertion loss is same as that of excess loss. State whether the given statement is true or false.

A four-port multimode fiber FBT coupler has 50 μWoptical power launched into port 1. The measured output power at ports 2,3 and 4 are 0.003, 23.0 and 24.5 μW respectively. Determine the excess loss.

A four-port FBT coupler has 60μW optical power launched into port one. The output powers at ports 2, 3, 4 are 0.0025, 18, and 22 μW respectively. Find the split ratio?

How many manufacturing methods are used for producing multimode fiber star couplers?