In data communication terminology, a transmission medium is a physical path between the transmitter and the receiver i.e. it is the channel through which data is sent from one place to another. Transmission Media is broadly classified into the following types: 1. Guided Media: It is also referred to as Wired or Bounded transmission
media. Signals being transmitted are directed and confined in a narrow pathway by using physical links.
There are 3 major types of Guided Media: (i) Twisted Pair Cable –
Advantages: ⇢ Least expensive ⇢ Easy to install ⇢ High-speed capacity Disadvantages: ⇢ Susceptible to external interference ⇢ Lower capacity and performance in comparison to STP ⇢ Short distance transmission due to attenuation Applications: Used in telephone connections and LAN networks
Advantages: ⇢ Better performance at a higher data rate in comparison to UTP ⇢ Eliminates crosstalk ⇢ Comparatively faster Disadvantages: ⇢ Comparatively difficult to install and manufacture ⇢ More expensive ⇢ Bulky Applications: The shielded twisted pair type of cable is most frequently used in extremely cold climates, where the additional layer of outer covering makes it perfect for withstanding such temperatures or for shielding the interior components. (ii) Coaxial Cable – Advantages:
Disadvantages:
Applications: Radio frequency signals are sent over coaxial wire. It can be used for cable television signal distribution, digital audio (S/PDIF), computer network connections (like Ethernet), and feedlines that connect radio transmitters and receivers to their antennas. (iii) Optical Fiber Cable – The cable can be unidirectional or bidirectional. The WDM (Wavelength Division Multiplexer) supports two modes, namely unidirectional and bidirectional mode. Advantages:
Disadvantages:
Applications: Radio frequency signals are sent over coaxial wire. It can be used for cable television signal distribution, digital audio (S/PDIF), computer network connections (like Ethernet), and feedlines that connect radio transmitters and receivers to their antennas. (iv) Stripline Stripline is a transverse electromagnetic (TEM) transmission line medium invented by Robert M. Barrett of the Air Force Cambridge Research Centre in the 1950s. Stripline is the earliest form of the planar transmission line. It uses a conducting material to transmit high-frequency waves it is also called a waveguide. This conducting material is sandwiched between two layers of the ground plane which are usually shorted to provide EMI immunity. (v) Microstripline In this, the conducting material is separated from the ground plane by a layer of dielectric. 2. Unguided Media: Features:
There are 3 types of Signals transmitted through unguided media: (i) Radio waves – Further Categorized as (i) Terrestrial and (ii) Satellite. (ii) Microwaves – (iii) Infrared – What is transmission medium and types?Transmission media are located below the physical layer and are controlled by the physical layer. Transmission media are also called communication channels. Transmission media are of two types − Guided Transmission Medium. Unguided Transmission Medium.
What are transmission mediums?A transmission medium is a system or substance that can mediate the propagation of signals for the purposes of telecommunication. Signals are typically imposed on a wave of some kind suitable for the chosen medium.
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