Recent questions tagged est

Description : The magnetic field of an antenna is perpendicular to the earth. The antenna’s polarization ___

Last Answer : is horizontal

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 : The property of interchangeability for the transmitting and receiving operations is known as ____

Last Answer : reciprocity

Description : The fields surrounding the antenna do not collapse their energy back into the antenna but rather radiate it out in space

Last Answer : radiation field

Description : It is the ratio of the radiated to the reflected energy:

Last Answer : Radiation efficiency

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 : The line bisecting the major lobe, or pointing from the center of the antenna in the direction of maximum radiation is called _____

Last Answer : line of shoot

Description : A special type of transmission line that consist of conducting metallic tube through which high frequency electromagnetic energy is propagated

Last Answer : waveguide

Description : If energy is applied at the geometrical center of antenna, the antenna is said to be ___

Last Answer : center-fed

Description : The radiation pattern of collinear and a broadside antenna is __

Last Answer : bidirectional

Description : Hertz antenna are predominantly used with frequencies above

Last Answer : 2MHz

Description : The point on the antenna where the transmission line is connected is called _____

Last Answer : feedpoint

Description : The discone antenna is

Last Answer : useful as a UHF receiving antenna

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 : ____ is a process-to-process protocol that adds only port addresses, checksum error control, and length information to the data from the upper layer.

Last Answer : UDP

Description : ______ are special-interest groups that quickly test, evaluate, and standardize new technologies

Last Answer : Forums

Description : _______ refers to the structure or format of the data, meaning the order in which they are presented.

Last Answer : Semantics

Description : ________ defines how a particular pattern to be interpreted, and what action is to be taken based on that interpretation.

Last Answer : syntax

Description : The effect of a large magnitude of the numerical aperture.

Last Answer : The amount of external light the fiber will accept is greater

Description : It is the figure of merit used to measure the magnitude of the acceptance angle.

Last Answer : numerical aperture

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 : It is caused by valence electrons in the silica material from which the fiber are manufactured.

Last Answer : ultraviolet absorption

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 : 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 : Laser light is very bright because it is:

Last Answer : coherent

Description : The process of moving from one energy level to another is called __

Last Answer : Absorption

Description : The process of decaying from one energy level to another energy level is called _______

Last Answer : Spontaneous emission

Description : Any energy above the ground state is called ________

Last Answer : excited state

Description : What phenomenon will result if the glass fiber is exposed to long periods of high humidity?

Last Answer : stress corrosion

Description : Developed an optical fiber with losses less that 2 dB/km

Last Answer : Kao and Bockham

Description : Optical power is sometimes called ____

Last Answer : Radiant flux

Description : The term single mode and multimode are best described as:

Last Answer : the number of wavelengths each fiber can support

Description : Photodiodes operate properly with:

Last Answer : reverse bias

Description : Range of wavelengths of ultraviolet

Last Answer : 10 nm to 390 nm

Description : Range of wavelength of visible light.

Last Answer : 390 nm to 770 nm

Description : Range of infrared.

Last Answer : 770 nm to 10^6 nm

Description : A popular light wavelength fiber-optic cable is

Last Answer : 1.3 micrometer

Description : Single-mode step-index cable has a core diameter in the range of

Last Answer : 2 to 15 micrometer

Description : It is caused by hydroxide ions in the material

Last Answer : ion resonance absorption

Description : A single fiber can handle as many voice channels as.

Last Answer : a 1500-pair cable The term power budgeting refers to: Ans. the total power available minus the attenuation losses

Description : EMD is best described by which statement?

Last Answer : . 70 percent of the core diameter and 70% of the fiber NA should be filled with light.

Description : The upper pulse rate and information carrying capacity of a cable is limited by:

Last Answer : modal dispersion

Description : Which type of fiber-optic cable is the most widely used?

Last Answer : multimode step-index

Description : A ________ is a set of rules that governs data communication

Last Answer : protocol

Description : In a waveguide, what is a frequency that would cause angles of incidence and reflection to be zero degrees?

Last Answer : Critical Frequency

Description : At what frequency compared to the cutoff frequency of a waveguide will the wavefronts be reflected back and forth across the guide (setting up standing waves) and no energy

Last Answer : UHF receiving antenna

Description : The size, shape, and dielectric material of a waveguide must be constant throughout its length for energy to move from one end to the other without reflections. What could be the effect in any abrupt change in its size or shape?

Last Answer : Reflections.

Description : What device can be constructed to allow microwave energy to pass in one direction but blocks energy in the other direction in a waveguide?

Last Answer : errite Isolato