Description : Does underfilling a multimode optical fiber excite mainly high-order or low-order modes?
Last Answer : Low-order modes.
Description : A mode filter is a device that attenuates specific modes propagating in the core of an optical fiber. What mode propagating along single mode fibers do mode filters eliminate?
Last Answer : Second-order mode.
Description : As the core and cladding modes travel along the fiber, mode coupling occurs. What is mode coupling?
Last Answer : Mode coupling is the exchange of power between two modes.
Description : Delay differences between the source wavelengths occur as the optical signal propagates along the fiber. What is this called?
Last Answer : Differential group delay t(l).
Description : A light ray incident on the optical fiber core is propagated along the fiber. Is the angle of incidence of the light ray entering the fiber larger or smaller than the acceptance angle
Last Answer : Smaller.
Description : Two methods describe how light propagates along an optical fiber. These methods define two theories of light propagation. What do we call these two theories?
Last Answer : The ray theory and the mode theory.
Description : Meridional rays are classified as either bound or unbound rays. Bound rays propagate through the fiber according to what property?
Last Answer : Total internal reflection.
Description : Is the different angle of entry of light into an optical fiber when the diameter of the core is many times the wavelength of the light transmitted. a. Acceptance angle b. Modes c. Sensors d. Aperture
Last Answer : b. Modes
Description : Is the different angle of entry of light into an optical fiber when the diameter of the core is many times the wavelength of the light transmitted. ∙ a. Acceptance angle ∙ b. Modes ∙ c. Sensors ∙ d. Aperture
Description : What four fiber properties determine the number of modes propagating in a multimode gradedindex fiber?
Last Answer : Numerical aperture (NA), relative refractive index difference ( D), profile parameter (α), and normalized frequency (V).
Description : Modes of a light pulse that enter the fiber at one time exit the fiber at different times. This condition causes the light pulse to spread. What is this condition called?
Last Answer : Modal dispersion.
Description : The number of modes propagated in a multimode fiber depends on core size and numerical aperture (NA). If the core size and the NA decrease, will the number of modes propagated increase or decrease?
Last Answer : Decrease.
Description : The fiber's normalized frequency (V) determines how many modes a fiber can support. As the value of V increases, will the number of modes supported by the fiber increase or decrease?
Last Answer : Increase.
Description : Which types of LEDs are the preferred optical sources for short-distance, low-data-rate fiber optic systems?
Last Answer : SLEDs and ELEDs.
Description : Give two reasons why optical fiber manufacturers depart from the traditional circular core and cladding, low-loss glass fiber design?
Last Answer : To increase performance and reduce cost
Description : Which type of optical splitter (Y-coupler or T-coupler) splits only a small amount of power from the input fiber to one of the output fibers?
Last Answer : T-coupler
Description : Which type of fiber optic connector (butt-jointed or expanded beam) brings the prepared ends of two optical fibers into close contact?
Last Answer : Butt-jointed connectors.
Description : What is the basic fiber cleaving technique for preparing optical fibers for coupling?
Last Answer : Score-and-break.
Description : Quality fiber-end preparation is essential for proper system operation. What properties must an optical fiber-end face have to ensure proper fiber connection?
Last Answer : Be flat, smooth, and perpendicular to the fiber axis.
Description : The amount of optical power coupled into an optical fiber depends on what four factors?
Last Answer : (1) The angles over which the light is emitted. (2) The size of the source's light-emitting area relative to the fiber core size. (3) The alignment of the source and fiber. (4) The coupling characteristics of the fiber (such as the NA and the refractive index profile)
Description : Which part of a fiber optic transmitter converts the processed electrical signal to an optical signal?
Last Answer : The optical source.
Description : Describe an optical fiber cable component (OFCC).
Last Answer : OFCCs are tight-buffer fiber surrounded by arimid yarn and a low-halogen outer jacket.
Description : Multimode optical fibers can have a step-index or graded index refractive index profile. Which fiber, multimode step-index or multimode graded-index fiber, usually performs better?
Last Answer : Multimode graded-index fiber
Description : List the two principal optical detectors used in fiber optic systems.
Last Answer : The semiconductor positive-intrinsic-negative (PIN) photodiode and avalanche photodiode (APD).
Description : If an installed optical fiber cable does not have connectors or terminations on both ends, how should the cable be tested?
Last Answer : With an OTDR unless it is less than 50 meters in length. If it is less than 50 meters in length, continuity should be verified with a flashlight.
Description : When is an optical power meter measurement recommended for conducting field measurements on installed optical fiber cables or cable plants?
Last Answer : When an installed optical fiber cable or cable plant is less than 50 meters in length.
Description : optical launch conditions exists if the launch spot size and angular distribution are larger than that of the fiber core?
Last Answer : Overfilled.
Description : What are the main causes of absorption in optical fiber?
Last Answer : Intrinsic and extrinsic material properties.
Description : What type of optical fiber operates below the cutoff
Last Answer : The order of a mode is indicated by the number of field maxima within the core of the fiber. The order of a mode is also determined by the angle that the wavefront makes with the axis of the fiber
Description : List the three parts of an optical fiber.
Last Answer : Core, cladding, and coating or buffer.
Description : The index of refraction measures the speed of light in an optical fiber. Will light travel faster in an optically dense material or in one that is less dense?
Last Answer : Light will travel faster in an optical material that is less dense.
Description : What is the basic optical-material property relevant to optical fiber light transmission?
Last Answer : The index of refraction.
Description : Which type of optical fiber (multimode or single mode) tends to have lower loss and produces less signal distortion?
Last Answer : Single mode fiber.
Description : In 1969, what did several scientists conclude about optical fiber loss?
Last Answer : mpurities in the fiber material caused the signal loss in optical fibers. The basic fiber material did not prevent the light signal from reaching the end of the fiber.
Description : What mechanisms in the fiber waveguides weaken and distort the optical signal?
Last Answer : Scattering, absorption, and dispersion.
Description : A wavefront undergoes a phase change as it travels along the fiber. If the wavefront transverses the fiber twice and is reflected twice and the total phase change is equal to 1/2 p, will the wavefront disappear? If yes, why?
Last Answer : Yes, the wavefront will disappear because the total amount of phase collected must be an integer multiple of 2 p. (If the propagating wavefronts are out of phase, they will disappear. ... interfere with the wavefronts out of phase. This type of interference is called destructive interference.)
Description : The mode theory uses electromagnetic wave behavior to describe the propagation of the light along the fiber. What is a set of guided electromagnetic waves called?
Last Answer : Modes of the fiber.
Description : The maximum angle in which external light rays may strike the air/glass interface and still propagate down the fiber. ∙ A. Acceptance cone half-angle ∙ B. Acceptance cone ∙ C. Critical angle ∙ D. Angle of incidence
Last Answer : A. Acceptance cone half-angle
Description : The maximum angle in which external light rays may strike the air/glass interface and still propagate down the fiber.
Last Answer : Acceptance cone half-angle
Description : To propagate energy down an arm of a hybrid ring duplexer, the two fields at the junction of the arm and the ring must have what phase relationship?
Last Answer : 180 degrees out of phase
Description : The value of the normalized frequency parameter (V) relates the core size with mode propagation. When single mode fibers propagate only the fundamental mode, what is the value of V?
Last Answer : V≤2.405.
Description : This first step inthe transaction processing cycle captures businessdata throughvarious modes suchas optical scanning orat an electronic commerce website– (A) Document and report generation (B) Database maintenance (C) Transaction processing startup (D) Data Entry
Last Answer : Data Entry
Description : Pick up the correct statement from the following (A) 1 second of arc corresponds to a displacement ratio of 1:206, 300 (B) 1 degree of arc corresponds to a displacement ratio of 1:57 (C) ... to propagate themselves along a traverse as the square root of the number of stations (D) All the above
Last Answer : (D) All the above
Description : The field arrangements in waveguides are divided into what two categories to describe the various modes of operation?
Last Answer : Transverse electric (TE) and transverse magnetic (TM).
Description : Debunching of the electron bunches in the higher modes of a reflex klystron has what effect on output power?
Last Answer : Power is reduced.
Description : What are the five most prominent communications modes of operation?
Last Answer : Simplex, half-duplex, semiduplex, duplex, and broadcast.
Description : What are the transmitter operating modes?
Last Answer : Lsb, usb, isb, AM, cw, fsk.
Description : What are the tuning modes for the coupler group discussed?
Last Answer : Automatic, semiautomatic, and manual.
Description : What are the two teletypewriter modes of operation?
Last Answer : Synchronous and nonsynchronous
Description : Modes that are bound at one wavelength may not exist at longer wavelengths. What is the wavelength at which a mode ceases to be bound called?
Last Answer : Cutoff wavelength