This is the summary notes of the important terms and concepts in Chapter 12 of the book "Electronic Communications System" by Wayne Tomasi. The notes are properly synchronized and concise for much better understanding of the book. Make sure to familiarize this review notes to increase the chance of passing the ECE Board Exam.
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CHAPTER 12 |
METALLIC CABLE TRANSMISSION MEDIA |
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Items |
Definitions |
Terms |
|
1 |
Provides a conduit in which electromagnetic signals are contained. |
Guided Transmission Media |
|
2 |
Emitted then radiated through air or a vacuum. |
Unguided Transmission Media |
|
3 |
Used to propagate electromagnetic signals between two locations in a communications 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 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. |
Frequency |
|
8 |
Currents that flow in opposite directions in a balanced wire pair. |
Metallic circuit currents |
|
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. |
Single-ended or unbalanced |
|
12 |
A circuit device used to connect a balanced transmission line to an unbalanced load. |
balun |
|
13 |
Most common metallic cables used to interconnect data communications systems and computer networks. |
Parallel-conductor transmission lines and coaxial transmission lines. |
|
14 |
Formed by twisting two insulated conductors around each other. |
Twisted-pair |
|
15 |
Types of twisted pair. |
Unshielded twisted pair and Shielded twisted pair |
|
16 |
Coupling that takes place when a transmitted signal is coupled into the received signal at the same end of the cable. |
Near-end crosstalk |
|
17 |
Standard color code specified by the EIA for CAT-5 cable. |
Pair 1: blue/white stripe and blue Pair 2: orange/white stripe and orange Pair 3: green/white stripe and green Pair 4: brown/white stripe and brown |
|
18 |
Woven into a mesh. |
Braid |
|
19 |
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 |
|
20 |
Used for high data transmission rates to reduce losses and isolate transmission path. |
Coaxial |
|
21 |
Refers to the woven stranded mesh that surrounds some types of coaxial cables. |
Shielding |
|
22 |
One layer of foil insulation and one layer of braided shielding. |
Dual shielded |
|
23 |
Types of coaxial cables. |
Rigid air-filled; solid flexible |
|
24 |
Uniformly distributed throughout the length of the line. |
Distributed parameters |
|
25 |
Transmission characteristics of a transmission line. |
Secondary constants |
|
26 |
Impedance seen looking into an infinitely long line. |
Surge impedance |
|
27 |
Expressed the attenuation and the phase shift per unit length of a transmission line. |
Propagation constants |
|
28 |
Ratio of the actual velocity of propagation of an electromagnetic wave through a given medium to the velocity of propagation through a vacuum. |
Velocity factor. |
|
29 |
Relative permittivity of a material. |
Dielectric constant |
|
30 |
Several ways in which signal power is lost. |
Conductor loss, radiation loss, dielectric heating loss, coupling loss and corona |
|
31 |
Voltage that propagates from the source toward the load. |
Incident voltage |
|
32 |
Voltage that propagates that propagates from the load toward the source. |
Reflected voltage |
|
33 |
Transmission line with no reflected power. |
Matched line |
|
34 |
Incident power returned (reflected) to the source. |
Unmatched or mismatched line |
|
35 |
Two travelling waves set up an interference pattern. |
Standing wave |
|
36 |
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 |
|
37 |
Used to match transmission lines to purely resistive loads whose resistance is not equal to the characteristic impedance of the line. |
Quarter-wavelength transformers |
|
38 |
A technique that can be used to locate an impairment in a metallic cable |
Time domain reflectometry (TDR) |
|
39 |
Return signal. |
Echo |
|
40 |
Simply a flat conductor separated from a ground plane by an insulating di-electric material. |
Microstrip |
|
41 |
Simply a flat conductor sandwiched between two ground planes. |
Stripline |
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