Description : The loss in signal power as light travels down the fiber is called ............. A) Attenuation B) Propagation C) Scattering D) Interruption
Last Answer : A) Attenuation
Description : The loss in signal power as light travels down a fiber is called a. Dispersion b. Scattering c. Absorption d. Attenuation
Last Answer : d. Attenuation
Description : The loss in signal power as light travels down a fiber is called ∙ a. Dispersion ∙ b. Scattering ∙ c. Absorption ∙ d. Attenuation
Last Answer : ∙ d. Attenuation
Description : ECE Board Exam November 1996 The loss in signal power as light travels down a fiber is A. attenuation B. propagation C. absorption D. scattering
Last Answer : A. attenuation
Description : Loss due to the diffraction of light when it strikes on the irregularities formed during the manufacturing process of the fiber optics. A. Absorption loss B. Attenuation C. Bending loss D. Rayleigh scattering loss
Last Answer : D. Rayleigh scattering loss
Description : Band loss is ∙ a. A reduction in transmitter power caused by earth’s surface curvature ∙ b. A reduction in strength of the signal caused by folded dipole bends ∙ c. An attenuation increase caused by bends radiating from the side of the fiber ∙ d. All of these
Last Answer : c. An attenuation increase caused by bends radiating from the side of the fiber
Description : Why are visible-light LEDs not used for fiber optics? ∙ a. It has high losses ∙ b. It has short wave ∙ c. It has low attenuation ∙ d. It has weak signal
Last Answer : ∙ a. It has high losses
Description : _________can impair a signal. A) Attenuation B) Distortion C) Noise D) All of theabove
Last Answer : All of theabove
Description : ________ is a typeof transmission impairment in which the signal loses strength due to the different propagation speeds of each frequency that makes up the signal. A) Attenuation B) Distortion C) Noise D) Decibel
Last Answer : Distortion
Description : ________ is a typeof transmission impairment in which the signal loses strength due to theresistance of the transmission medium. A) Attenuation B) Distortion C) Noise D) Decibel
Last Answer : Attenuation
Description : Attenuation and noise can impair a signal. True False
Last Answer : True
Description : It is caused by the difference in the propagation time of light rays that take different paths down the fiber. ∙ A. modal dispersion ∙ B. microbending ∙ C. Rayleigh scattering ∙ D. chromatic dispersion
Last Answer : A. modal dispersion
Description : The term power budgeting refers to ∙ A. the cost of cable, connectors, equipment and installation ∙ B. the loss of power due to defective components ∙ C. the total power available minus the attenuation losses ∙ D. the comparative costs of fiber and copper installations
Last Answer : C. the total power available minus the attenuation losses
Description : When connector losses, splice losses and coupler losses are added, what is the limiting factor? ∙ A. source power ∙ B. fiber attenuation ∙ C. connector and splice loss ∙ D. detector sensitivity
Last Answer : D. detector sensitivity
Description : If the length of the fiber point defect changes with pulse duration, is the OTDR signal deviation a point defect or a region of high fiber attenuation?
Last Answer : A point defect.
Description : The _______ is thephysicalpath over which a message travels. A) Protocol B) Medium C) Signal D) All the above
Last Answer : Medium
Description : A fiber-optic cable has a loss of 15 dB/km. The attenuation in a cable 1000 ft. long is ∙ A. 4.57 dB ∙ B. 9.3 dB ∙ C. 24 dB ∙ D. 49.2 dB
Last Answer : A. 4.57 dB
Description : Fiber-optic cables with attenuation of 1.8, 3.4, 5.9 and 18 dB are linked together. The total loss is ∙ A. 7.5 dB ∙ B. 19.8 dB ∙ C. 29.1 dB ∙ D. 650 dB
Last Answer : C. 29.1 dB
Description : Which is not a possible cause of optical fiber loss? ∙ a. Impurities ∙ b. Glass attenuation ∙ c. Stepped index operation ∙ d. Microbending
Last Answer : ∙ c. Stepped index operation
Description : Under normal condition, a single fiber should not be used for a two-way communication mainly because of ∙ a. Loss ∙ b. Fading ∙ c. Noise ∙ d. Attenuation
Last Answer : ∙ c. Noise
Description : . A fiber-optic cable has a loss of 15 dB/km. The attenuation in a cable, 100 ft long is ∙ a. 4.57 dB ∙ b. 9.3 dB ∙ c. 24 dB ∙ d. 49.2 dB
Last Answer : ∙ a. 4.57 dB
Description : The dominant loss mechanisms in silica fiber are ∙ a. Absorption and radiation losses ∙ b. Absorption and Rayleigh scattering ∙ c. Coupling and radiation losses ∙ d. Radiation and modal dispersion
Last Answer : b. Absorption and Rayleigh scattering
Description : Explain absorption loss and scattering loss occurs in optical fiber.
Last Answer : Scattering loss:- Basically, scattering losses are caused by the interaction of light with density fluctuations within a fiber. Density changes are produced when optical fibers are manufactured. ... glass material. iii. Intrinsic absorption by the basic constituent atoms of the fiber material.
Description : Results in reduction in the power of light wave as it travels down the cable. ∙ A. power loss ∙ B. absorption loss ∙ C. resistive loss ∙ D. heat loss
Last Answer : A. power loss
Description : Scattering losses are caused by the interaction of light with density fluctuations within a fiber. What are the two scattering mechanisms called when the size of the density fluctuations is (a) greater than and (b) less than one-tenth of the operating wavelength?
Last Answer : . (a) Mie scattering; (b) Rayleigh scattering.
Description : The following are the cause of light attenuation in fiber optics except ∙ a. Backscattering ∙ b. Absorption ∙ c. Refraction ∙ d. Microbends
Last Answer : c. Refraction
Description : When the wave travels in a conducting medium, the rate of attenuation is decided by
Last Answer : When the wave travels in a conducting medium, the rate of attenuation is decided by Both attenuation constant and phase constant
Description : In a fiber-optic cable, the signal is propagatedalong theinner core by _______. A) reflection B) refraction C) modulation D) none of the above
Last Answer : reflection
Description : The physical layer provides __________ a. mechanical specifications of electrical connectors and cables b. electrical specification of transmission line signal level c. specification for IR over optical fiber d. all of the mentioned
Last Answer : d. all of the mentioned
Description : The physical layer provides __________ A. mechanical specifications of electrical connectors and cables B. electrical specification of transmission line signal level C. specification for IR over optical fiber D. all of the mentioned
Last Answer : D. all of the mentioned
Description : What specifications does physical layer provides __________. A. mechanical specifications of electrical connectors and cables B. electrical specification of transmission line signal level C. specification for IR over optical fiber D. all of the mentioned
Description : Fiber optics posses following properties __________ a) Immune electromagnetic interference b) Very less signal attenuation c) Very hard to tap d) All of the mentioned
Last Answer : d) All of the mentioned
Description : The physical layer provides __________ a) mechanical specifications of electrical connectors and cables b) electrical specification of transmission line signal level c) specification for IR over optical fiber d) all of the mentioned
Last Answer : d) all of the mentioned
Description : When a beam of light travels through media of two different densities, if theangle of incidence isgreater than the critical angle, _______ occurs. A) reflection B) refraction C) incidence D) criticism
Description : When connectorlosses,splice losses, and couplerlosses are added,whatisthe finallimitingfactor? a. Source power b. Fiber attenuation c. Connector and splice losses d. Detector sensitivity
Last Answer : d. Detector sensitivity
Description : How much power (roughly) a light emitting diode can couple into an optical fiber? a. 100 microwatts b. 440 microwatts c. 100 picowatts d. 10 miliwatts
Last Answer : 100 microwatts
Description : Block coding can help in _______at the receiver. A) Synchronization B) Error detection C) Attenuation D) (a) and (b)
Last Answer : (a) and (b)
Description : _______ is a typeof transmission impairment in which an outside sourcesuch as crosstalk corrupts asignal. A) Attenuation B) Distortion C) Noise D) Decibel
Last Answer : Noise
Description : Computers cannot communicate with each other directly over telephone lines because they usedigitalpulses whereas telephone lines useanalog sound frequencies. What is the name of the device which permits digital to analog ... A. Interface B. Modem C. Attenuation D. Teleprocessor E. None of the above
Last Answer : Modem
Description : Which of the following summation operations is performed onthe bits to checkanerror-detecting code? A. Codec B. Coder-decoder C. Checksum D. Attenuation
Last Answer : Checksum
Description : Light travels faster in a material with a lower refractive index. Therefore, light rays that travel a longer distance in a lower refractive index travel at a greater average velocity. What effect does this have on multimode graded-index fiber modal dispersion and bandwidth?
Last Answer : Decreases the time difference between light rays, which reduces modal dispersion and increases fiber bandwidth.
Description : The patient with cardiac failure is taught to report which of the following symptoms to the physician or clinic immediately? a) Persistent cough Persistent cough may indicate an onset of ... sleep through the night Frequent urination, causing interruption of sleep, should be reported immediately.
Last Answer : a) Persistent cough Persistent cough may indicate an onset of left-heart failure.
Description : What is the term for the ratio of actual velocity at which a signal travels through a line to the speed of light in a vacuum? A. Velocity factor B. Characteristic impedance C. Surge impedance D. Standing wave ratio
Last Answer : A. Velocity factor
Description : Why is a dead-zone fiber placed between the test fiber and OTDR when conducting attenuation measurements?
Last Answer : To reduce the effect of the initial reflection at the OTDR
Description : in multimode fibers, how do fiber joints increase fiber attenuation following the joint?
Last Answer : By disturbing the fiber's mode power distribution (MPD).
Description : What two properties of the launch condition may affect multimode fiber attenuation measurements?
Last Answer : . Launch spot size and angular distribution.
Description : Which of the following is not a factor in cable light loss? ∙ A. reflection ∙ B. absorption ∙ C. scattering ∙ D. dispersion
Last Answer : A. reflection
Description : Which of the following is not a factor in cable light loss? ∙ a. Reflection ∙ b. Absorption ∙ c. Scattering ∙ d. Dispersion
Last Answer : ∙ a. Reflection