Provides a conduit in which electromagnetic signals are contained.
2)
Emitted then radiated through air or a vacuum.
3)
Used to propagate pr opagate electromagnetic signals between two locations in a communications co mmunications system.
Cable Transmission Medium
4)
Most common means of interconnecting devices in local area networks.
Cable Transmission Systems
5)
Metallic conductor system used to transfer tr ansfer electrical energy from one point to another using electrical current flow.
Transmission line
6)
Two basic kinds of waves.
longitudinal and transverse
7)
The rate at which the periodic wave repeats.
8)
Currents that flow in opposite directions in a balanced wire pair.
9)
Currents that flow in the same direction.
Longitudinal currents
10)
Cancellation of common mode signals.
Common mode rejection
11)
One wire is at the ground potential, whereas the other is at signal potential.
12)
A circuit device used to connect a balanced transmission line to an unbalanced load.
Prepared By : MA. ELAINE L. CORTEZ
Guided Transmission Media Unguided Transmission Media
Frequency
Metallic circuit currents
Single-ended or unbalanced
balun
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BOOK REVIEW IN COMMUNICATIONS
Electronic Communications System By Wayne Tomasi
14)
Most common metallic cables used to interconnect data communications systems and computer networks.
Parallel-conductor transmission lines and coaxial transmission lines.
15)
Formed by twisting two insulated conductors around each other.
Twisted-pair
16)
Types of twisted pair.
17)
Coupling that takes place when a transmitted signal is coupled into the received signal at the same end of the cable.
Unshielded twisted pair and Shielded twisted pair
Near-end crosstalk
Pair 1: blue/white stripe and blue Pair 2: orange/white stripe and orange Pair 3: green/white strip[e and green Pair 4: brown/white stripe and brown
18)
Standard color code specified by the EIA for CAT-5 cable.
19)
Woven into a mesh.
20)
Name given to the area between the ceiling and the root in a single-story building or between the ceiling and the floor of the next higher level in a multi-story building.
Plenum
21)
Used for high data transmission rates to reduce losses and isolate transmission path.
Coaxial
22)
Refers to the woven stranded mesh that surrounds some types of coaxial cables.
23)
One layer of foil insulation and one layer of braided shielding.
Prepared By : MA. ELAINE L. CORTEZ
Braid
Shielding
Dual shielded
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BOOK REVIEW IN COMMUNICATIONS
Electronic Communications System By Wayne Tomasi
Rigid air-filled; solid flexible
24)
Types of coaxial cables.
26)
Uniformly distributed throughout the length of the line.
27)
Transmission characteristics of a transmission line.
28)
Impedance seen looking into an infinitely long line.
Surge impedance
29)
Expressed the attenuation and the phase shift per unit length of a transmission line.
Propagation constants
30)
Ratio of the actual velocity of propagation of an electromagnetic wave through a given medium to the velocity of propagation through a vacuum.
31)
Relative permittivity of a material.
32)
Several ways in which signal power is lost.
33)
Voltage that propagates from the source toward the load.
34)
Voltage that propagates that propagates from the load toward the source.
35)
Transmission line with no reflected power.
36)
Vector quantity that represents the ratio of reflected voltage to incident voltage or reflected current to incident current.
37)
Incident power is absorbed by the load.
Prepared By : MA. ELAINE L. CORTEZ
Distributed parameters
Secondary constants
Velocity factor.
Dielectric constant Conductor loss, radiation loss, dielectric heating loss, coupling loss and corona Incident voltage
Reflected voltage
Flat or non resonant line
Reflection coefficient
Matched line 80
BOOK REVIEW IN COMMUNICATIONS
Electronic Communications System By Wayne Tomasi
Unmatched or mismatched line
38)
Incident power returned (reflected) to the source.
39)
Two travelling waves set up an interference pattern.
40)
Ratio of the maximum voltage to the minimum voltage or the maximum current to the minimum current of a standing wave on a transmission line.
Standing-wave ratio
41)
Used to matched transmission lines to purely resistive loads whose resistance is not equal to the characteristic impedance of the line.
Quarter-wavelength transformers
42)
A technique that can be used to locate an impairment in a metallic cable
Time domain reflectometry (TDR)
43)
Return signal.
44)
Simply a flat conductor separated from a ground plane by an insulating di-electric material.
Microstrip
45)
Simply a flat conductor sandwiched between two ground planes.
