Prerequisite – Types of Transmission Media
In this type of media, signal energy is enclosed and guided within a solid medium. The guided media is used either for point to point link or a shared link with various connections. In guided media, interference is generated by emissions in the adjacent cables. Proper shielding of guided media is required to reduce the interference issue.
In the unguided media, the signal energy propagates through a wireless medium. The wireless media is used for radio broadcasting in all directions. Microwave links are chosen for long distance broadcasting transmission unguided media. Interference is also a problem in unguided media, overlapping frequency bands from competing signals can alter or eliminate a signal.
Let’s see the difference between the Guided Media and Unguided Media:
|S.No.||Guided Media||Unguided Media|
|1.||The signal energy propagates through wires in guided media.||The signal energy propagates through air in unguided media.|
|2.||Guided media is used for point to point communication.||Unguided media is generally suited for radio broadcasting in all directions.|
|3.||Discrete network topologies are formed by the guided media.||Continuous network topologies are formed by the unguided media.|
|4.||Signals are in the form of voltage, current or photons in the guided media.||Signals are in the form of electromagnetic waves in unguided media.|
|5.||<Examples of guided media are twisted pair wires, coaxial cables, optical fiber cables.||Examples of unguided media are microwave or radio links and infrared light.|
|6.||By adding more wires, the transmission capacity can be increased in guided media.||It is not possible to obtain additional capacity in unguided media.|