Description : The minimum optical power a light detector can receive and still produce a usable electrical output signal. ∙ A. light responsivity ∙ B. light sensitivity ∙ C. light collectivity ∙ D. illumination
Last Answer : B. light sensitivity
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 term responsivity as it applies to a light detector is best described as.
Description : Optical power is sometimes called ____
Last Answer : Radiant flux
Description : Developed an optical fiber with losses less that 2 dB/km
Last Answer : Kao and Bockham
Description : The scientist who built the first optical maser.
Last Answer : Theodore Maiman
Description : Approximately what is the frequency limit of the optical fiber?
Last Answer : 40 GHz
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 : The modulated picture carrier wave includes the composite video signal as the:
Last Answer : Symmetric envelope of amplitude variations
Description : A 4.5-MHz signal which is equal to the difference between the picture and sound RF carrier frequencies in a 6-MHz TV channel.
Last Answer : Intercarrier frequencY
Description : The service are in standard AM broadcast is described as ______ if there is no fading of signal.
Last Answer : Primary
Description : The total bandwidth of an NTSC TV signal is:
Last Answer : . 6 MHz
Description : The most critical and difficult part of receiving a direct – sequence spread spectrum signal is :
Last Answer : Synchronism
Last Answer : 6 MHz
Description : To a conventional narrowband receiver, a spread spectrum signal appears to be
Last Answer : Noise
Description : The phase relationship between signaling elements for BPSK is the optimum signaling format and occurs only when two binary signal levels are allowed and when one signal is the exact negative of the other
Last Answer : Antipodal signaling
Description : A pulse modulation technique as the width of a constant amplitude pulse is varied proportional to the amplitude of the analog signal at the time the signal is sampled.
Last Answer : PWM, PLM, PDM
Description : The slope of the analog signal is greater than the delta modulator can maintain
Last Answer : Slope overload
Description : Rate of change of a signal on a transmission medium after encoding and modulation have occurred
Last Answer : baud rate
Description : Used for transmission of PCM encoded time – division multiplexed digital signal.
Last Answer : T carriers
Description : The signal from a satellite is normally aimed at a specific area called the ________
Last Answer : footprint
Description : Which device can produce the final product of machine processing into a form usable by humans: a) Storage b) Input Device c) Output Device d) None of The Above
Last Answer : c) Output Device
Description : The final output of a multiplexer
Last Answer : Composite baseband
Description : It is analogous to power dissipation to copper cables, impurities in the fiber absorb the light and covert it to heaT
Last Answer : absorption loss
Description : As light is coupled in a multiport deflective device, the power is reduced by:
Last Answer : 0.5 dB
Description : A theory that establishes the minimum sampling rate that can be used for a given PCM systems.
Last Answer : Nyquist sampling theorem
Description : A theory that establishes the minimum sampling rate that can be used for a given PCM systems
Description : It is used to encode the minimum amount of speech information necessary to reproduce a perceptible message with a fewer bits that those needed by a conventional encoder/decoder
Last Answer : vocoders
Description : The reason a CSMA/CD network has a minimum length for packets is:
Last Answer : to make sure all other nodes hear a collision in progress
Description : It is the ratio of the transmission bit rate to the minimum bandwidth required for a particular modulation scheme
Last Answer : Bandwidth efficiency, Information density, or Spectral efficiency
Description : It is a result of photons of light that are absorbed by the atoms of the glass core molecule
Last Answer : infrared absorption
Description : Laser light is very bright because it is:
Last Answer : coherent
Description : Range of wavelength of visible light.
Last Answer : 390 nm to 770 nm
Description : A popular light wavelength fiber-optic cable is
Last Answer : 1.3 micrometer
Description : “When visible light of high frequency electromagnetic radiation illuminates a metallic surface, electrons are emitted”
Last Answer : Plank’s law
Description : The time it takes a light induced carrier travel across the depletion region of the semiconductor.
Last Answer : . transit time
Description : They wrote a paper describing how it was possible to use stimulated emission for amplifying light waves (laser) as well as microwaves (maser).
Last Answer : Charles Townes and Arthur Schawlow
Description : They experimented with light transmission cables through bundle of fibers and lead to the development of flexible fiberscope
Last Answer : Van Heel, Hopkins and Kapany
Description : A temperature instrumentation system for an engine room console consists of a resistance temperature detector (RTD), a measuring bridge circuit, and a meter (or alarm circuit).Which of the following ... is zero. D. The input voltage of the resistance bridge is the constant temperature signal.
Last Answer : Answer: C
Description : How is the output signal developed in the common-emitter detector?
Last Answer : By the collector current flow through R4.
Description : The input to a coherent detector is DSB-SC signal plus noise. The noise at the detector output is: (1) The in-phase component (2) The quadrature-component (3) Zero (4) The envelope
Last Answer : The input to a coherent detector is DSB-SC signal plus noise. The noise at the detector output is: Zero.
Description : Which performance parameter is the minimum amount of optical power required to achieve a specific bit-error rate (BER) in digital systems or a given signal-to-noise ratio (SNR) in analog systems?
Last Answer : Receiver sensitivity.
Description : It is the ratio of the power density radiated in a particular direction to the power density radiated to the same point by a reference antenna, assuming both antennas are radiating the same amount of power
Last Answer : directive gain
Description : It is the resistance that, if it replaced the antenna, would dissipate exactly the same amount of power that the antenna radiates
Last Answer : . Radiation resistance
Description : Plots of field strength or power density with respect to the value at a reference point.
Last Answer : relative radiation pattern
Description : The radiation pattern plotted in terms of electric field strength or power density
Last Answer : absolute radiation pattern
Description : It is the same with directive gain except that the total power fed to the antenna is used and the antenna efficiency is taken into account.
Last Answer : power gain
Description : The final power amplifier in an FM transmitter usually operates class ___
Last Answer : C
Description : The final power amplifier in an FM transmitter usually operates class ______.