Description : Calculate the total rise time for a fiber-optic system if the transmitter, receiver, and cable each have a rise time of 50 nanoseconds.
Last Answer : 86.6 nanoseconds
Description : It indicates what signal frequencies can be propagated through a given distance of fiber cable. ∙ A. Bandwidth Distance Product ∙ B. Pulse width dispersion ∙ C. Rise time ∙ D. Cutoff frequency
Last Answer : A. Bandwidth Distance Product
Description : For laser diodes, the term ____________________ is used instead of bandwidth.
Last Answer : linewidth
Description : The main benefit of light wave communications over microwaves or any other communications media are ∙ A. lower cost ∙ B. better security ∙ C. wider bandwidth ∙ D. freedom from interface
Last Answer : C. wider bandwidth
Description : For a 300-m optical fiber cable with a bandwidth distance product of 600 MHz-km, determine the bandwidth. ∙ A. 5 GHz ∙ B. 1 GHz ∙ C. 2 GHz
Last Answer : C. 2 GHz
Description : The energy of the photon is ∙ a. Directly proportional to its bandwidth ∙ b. Directly proportional to the Planck’s constant ∙ c. Directly proportional to Boltzmann’s constant ∙ d. Inversely proportional to the Planck’s constant
Last Answer : Directly proportional to the Planck’s constant
Description : Which optical detector is used when high sensitivity and bandwidth are required? ∙ a. PMT ∙ b. APD ∙ c. PIN ∙ d. Phototransistor
Last Answer : a. PMT
Description : The bandwidth of a fiber is limited by ∙ a. Mode ∙ b. Wavelength ∙ c. Dispersion ∙ d. Frequency
Last Answer : c. Dispersion
Description : How many longitudinal modes can fall within a laser’s gain bandwidth? ∙ a. 2 ∙ b. 5 ∙ c. 9 ∙ d. No fixed limit, dependent on bandwidth and mode spacing
Last Answer : ∙ d. No fixed limit, dependent on bandwidth and mode spacing
Description : The main benefit of light-wave communications over microwaves or any other communications media is ∙ a. Lower cost ∙ b. Better security ∙ c. Wider bandwidth ∙ d. Freedom from interference
Last Answer : c. Wider bandwidth
Description : Which of the following contributes to the broadening of laser emission bandwidth? ∙ a. Doppler shift of moving atoms and molecules ∙ b. Amplification within the laser medium ∙ c. Coherence of the laser light ∙ d. Optical pumping of the laser transition
Last Answer : Doppler shift of moving atoms and molecules
Description : Is the width of the range of wavelengths emitted by the light source ∙ a. Bandwidth ∙ b. Chromatic Dispersion ∙ c. Spectral width ∙ d. Beamwidth
Last Answer : c. Spectral width
Description : The bandwidth of optical fiber ∙ a. 900M Hz ∙ b. 900 PHz ∙ c. 900 THz ∙ d. 900 EHz
Last Answer : c. 900 THz
Description : What particular circuit that rids FM of noise? A. HPF B. Phase shifter C. Limiter D. LPF
Last Answer : C. Limiter
Description : In fiber optics, higher-order mode refers to ∙ a. Cladding boundary at high angle ∙ b. Backscattering electromagnetic signals ∙ c. Diffracting signals ∙ d. All of these
Last Answer : ∙ a. Cladding boundary at high angle
Description : The processing speed of first generation computers was A) milliseconds B) microseconds C) nanoseconds D) picoseconds
Last Answer : Answer : A
Description : How many nanoseconds does it take for light to go 1 meter ?
Last Answer : It takes 3.3 nanoseconds for light to reach 1 meter.
Description : The operating speed of third generation computer was A) Milliseconds B) Microseconds C) Nanoseconds D) Picoseconds
Last Answer : Answer : C
Description : An eight stage ripple counter uses a flip-flop with propagation delay of 75 nanoseconds. The pulse width of the strobe is 50ns. The frequency of the input signal which can be used for proper operation of the counter is approximately (A) 1 MHz. (B) 500 MHz. (C) 2 MHz. (D) 4 MHz.
Last Answer : Maximum time taken for all flip-flops to stabilize is 75ns x 8 + 50 = 650ns. Frequency of operation must be less than 1/650ns = 1.5 MHz.
Description : While designing a stair, the product of rise and going is approximately kept equal to (A) 350 (B) 420 (C) 450 (D) 500
Last Answer : Answer: Option B
Description : Sum of tread and rise must lie between (A) 300 to 350 mm (B) 400 to 450 mm (C) 500 to 550 mm (D) 600 to 650 mm
Description : The term responsivity as it applies to a light detector is best described as ∙ A. the time required for the signal to go from 10 to 90 percent of maximum amplitude ∙ B. the ratio of the diode ... . the ratio of the input power to output power ∙ D. the ratio of output current to input current
Last Answer : the ratio of the diode output current to the input optical power
Description : The time it takes a light induced carrier travel across the depletion region of the semiconductor. ∙ A. dispersion ∙ B. response time ∙ C. irradiance ∙ D. transit time
Last Answer : D. transit time
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 : Light rays that are emitted simultaneously from an LED and propagated down an optical fiber do not arrive at the far end of the fiber at the same time results to ∙ A. intramodal dispersion ∙ B. pulse length dispersion ∙ C. modal dispersion ∙ D. wavelength dispersion
Last Answer : D. wavelength dispersion
Description : The three major groups of the optical system are ∙ A. the components, the data rate and the response time ∙ B. the source, the link and the receiver ∙ C. the transmitter, the cable and the receiver ∙ D. the source, the link and the detector
Last Answer : B. the source, the link and the receiver
Description : It is described as the flow of light energy past a given point in a specified time ∙ A. Optical radiation ∙ B. Optical impedance ∙ C. Optical illusion ∙ D. Optical power
Last Answer : D. Optical power
Description : OTDR stands for ∙ a. Optical Time Domain Reflectometer ∙ b. Optical Transmit Direction Return ∙ c. Optical Time Domain Time Regeneration ∙ d. Overtime Direct Reference
Last Answer : c. Optical Time Domain Time Regeneration
Description : One of the following is not a characteristic of light detectors. ∙ a. Responsitivity ∙ b. Spectral response ∙ c. Transmit time ∙ d. Dispersion
Last Answer : ∙ d. Dispersion
Description : What parameter of light detector determines the range or system length that can be achieved for a given wavelength? ∙ a. Transit time ∙ b. Spectral response ∙ c. Dark current ∙ d. Responsitivity
Last Answer : ∙ b. Spectral response
Description : Which is the proper measurement of average power emitted by a pulsed laser? ∙ a. Energy x time ∙ b. Pulse energy x repetition rate ∙ c. Pulse energy / repetition rate ∙ d. Peak power x pulse length
Last Answer : ∙ b. Pulse energy x repetition rate
Description : OTDR stands for: a. Optical Time-Delay Response b. Optical Timing Delay Requirement c. Optical Time-Domain Reflectometer d. Optical Time-Division Relay
Last Answer : c. Optical Time-Domain Reflectometer
Description : The scientist who built the first optical maser ∙ A. Charles Townes ∙ B. GA Bockham ∙ C. Theodore Maiman ∙ D. ACS Van Heel
Last Answer : ∙ C. Theodore Maiman
Description : The first laser emitted ∙ a. Pulses of 694 nm red light ∙ b. A continuous red beam ∙ c. Pulses of white light from a helical flash lamp ∙ d. Spontaneous emission
Last Answer : ∙ a. Pulses of 694 nm red light
Description : Developed the first laser a. Charles Townes b. Theodore Maiman c. Gordon McKenzie d. Albert Einstein
Last Answer : b. Theodore Maiman
Description : Define fiber optics.
Last Answer : Fiber optics is the branch of optical technology concerned with the transmission of radiant power (light energy) through fibers.
Description : In SONET, SPE stands for synchronous payload ____________________.
Last Answer : envelope
Description : SONET frame rows contain path overhead and ____________________ overhead.
Last Answer : transport
Description : The number of path overhead bytes in a SONET frame row is ____________________.
Last Answer : 1
Description : The total number of overhead bytes in a SONET frame row is ____________________.
Last Answer : 4
Description : The number of rows in a SONET frame is ____________________.
Last Answer : 9
Description : The number of bytes in the payload of a SONET frame is ____________________.
Last Answer : 774
Description : The number of bytes in a SONET frame is ____________________.
Last Answer : 810
Description : SONET frames have considerably more ____________________ than do DS frames for information about signal routing and setup.
Last Answer : overhead
Description : The data rate of an FDDI system is ____________________ bps.
Last Answer : 100 M
Description : FDDI uses ____________________ mode cables.
Last Answer : multi
Description : Each ____________________ in an FDDI system acts as a regenerative repeater.
Last Answer : node
Description : The two rings of an FDDI system carry data in ____________________ directions.
Last Answer : opposite
Description : FDDI systems use two ____________________ rings to carry signals.
Last Answer : token
Description : SONET uses a ____________________ to denote the starting position of an information frame.
Last Answer : pointer