Presentation overview of Transmission Media

Golis University, Faculty of Telecommunication Engineering Students Graduation Project

Project team

1. A2. A3. S4. M

Introduction

• Technology has advanced so much in the last decade or two that it has made life more efficient and comfortable. The comfort of being able to take control of devices from one particular location has become imperative as it saves a lot of Time and effort. Especially in the case of telecommunication engineering, transmission media has brought a tangible change in the lives of many people in the world today

Objectives

• The main objective of this project is to elaborate what transmission medium is all about and as well open to any telecommunication professional, students and information hunter who requires to find something about transmission media

• The specific objectives of this project are:1. to help students know about the history of transmission

media, reference literatures and the least developments.2. To show how we project team has understood the course of

transmission media in our telecommunication engineering degree career and testify our attainment and success in learning the course.

Limitation during the projectDuring this project we faced certain challenges/limitations which are as follows:•Insufficient time because as students taking our classes and doing the project was time constraint.•group working was difficult since the students reside in different places in the city •In some times we met lack of resource because the university haven’t sufficient library to find all the books we need and also availability of components was limited.•The constriction of the transmission media was so complicated which lead us to assemble and disassemble it many times.•Furthermore this topic lacks of prior searching studies on the project also lack of reference and books that talk about transmission media system

Transmission Media: What it is all about

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Transmission medium provides physical entity for the conveyance of signals. Transmission medium is the physical path between transmitter and receiver in a data transmission system. Transmission media can be classified as guided or unguided. In both cases, communication is in the form of electromagnetic waves. With guided media, the waves are guided along a solid medium, such as copper twisted pair, copper coaxial cable, and optical fiber. The atmosphere and outer space are examples of unguided media that provide a means of transmitting electromagnetic signals but do not guide them; this form of transmission is usually referred to as wireless transmission.

• For unguided media, the bandwidth of the signal produced by the transmitting antenna is more important than the medium in determining transmission characteristics. One key property of signals transmitted by antenna is directionality. In general, signals at lower frequencies are omnidirectional; that is, the signal propagates in all directions from the antenna. At higher frequencies, it is possible to focus the signal into a directional beam.

A number of design factors relating to the transmission medium and to the signal determine the data rate and distance:•Bandwidth. All other factors remaining constant, the greater the bandwidth of a signal, the higher the data rate that can be achieved. •Transmission impairments. Impairments, such as attenuation, limit the distance. For guided media, twisted pair generally suffers more impairment than coaxial cable, which in turn suffers more than optical fiber. •Interference. Interference from competing signals in overlapping frequency bands can distort or wipe out a signal. •Number of receivers. A guided medium can be used to construct a point-to-point link or a shared link with multiple attachments.

Transmission Medium

• transmission medium is a material substance (solid, liquid, gas, or plasma) that can propagate energy waves. For example, the transmission medium for sounds is usually air, but solids and liquids may also act as transmission media for sound.

• The term transmission medium also refers to a technical device that employs the material substance to transmit or guide waves. Thus, an optical fiber or a copper cable is a transmission medium. Not only is this but also able to guide the transmission of networks.

• Transmission media are the physical pathways that connect computers, other devices, and people on a network—the highways and byways that comprise the information superhighway. Each transmission medium requires specialized network hardware that has to be compatible with that medium. You have probably heard terms such as Layer 1, Layer 2, and so on. These refer to the OSI reference model, which defines network hardware and services in terms of the functions they perform. (The OSI reference model is discussed in detail in Chapter 5, "Data Communications Basics.") Transmission media operate at Layer 1 of the OSI model: They encompass the physical entity and describe the types of highways on which voice and data can travel. It would be convenient to construct a network of only one medium. But that is impractical for anything but an extremely small network.

In general, networks use combinations of media types. There are three main categories of media types:•Copper cable—Types of cable include unshielded twisted-pair (UTP), shielded twisted-pair (STP), and coaxial cable.•Wireless—Wireless media include radio frequencies, microwave, satellite, and infrared. •Fiber optics—Fiber offers enormous bandwidth, immunity to many types of interference and noise, and improved security. Therefore, fiber provides very clear communications and a relatively noise-free environment. The downside of fiber is that it is costly to purchase and deploy because it requires specialized equipment and techniques.

History of transmission media• Mathematical analysis of the behavior of electrical transmission lines grew

out of the work of James Clerk Maxwell, Lord Kelvin and Oliver Heaviside. • In 1855 Lord Kelvin formulated a diffusion model of the current in a

submarine cable. • In 1885 Heaviside published the first papers that described his analysis of

propagation in cables and the modern form of the telegrapher's equations.

• Michael Faraday and Wheatstone soon discovered the merits of gutta-percha as an insulator, and in 1845, the latter suggested that it should be employed to cover the wire which was proposed to be laid from Dover to Calais.

• In 1849, C.V. Walker, electrician to the South Eastern Railway, submerged a two-mile wire coated with gutta-percha off the coast from Folkestone, which was tested successfully.

First commercial cables• A telegraph stamp of the British & Irish Magnetic Telegraph Co. Limited (c. 1862).• Having earlier obtained a concession from the French Government, in August 1850

John Watkins Brett's Anglo-French Telegraph Company laid the first line across the English Channel, using the converted tugGoliath. It was simply a copper wire coated with gutta-percha, without any other protection, and was not successful.

• In 1853 further successful cables were laid, linking Great Britain with Ireland, Belgium and the Netherlands, and crossing The Belts in Denmark.

• The British & Irish Magnetic Telegraph Company completed the first successful Irish link on May 23 between Portpatrick and Donaghadee using the collierWilliam Hutt.

• The same ship was used for the link from Dover to Ostend in Belgium, by the Submarine Telegraph Company. Meanwhile, the Electric & International Telegraph Company completed two cables across the North Sea, from Orford Ness to Scheveningen, The Netherlands. They were laid by the Monarch, a paddle steamer which later became

the first vessel with permanent cable-laying equipment.

Data and information

The words Data and Information may look similar and many people use these words very frequently, But both have lots of differences between them.• Data are plain facts. The word "data" is plural for "datum." When data are processed, organized, structured or presented in a given context so as to make them useful, they are called Information.•It is not enough to have data (such as statistics on the economy). Data themselves are fairly useless, but when these data are interpreted and processed to determine its true meaning, they becomes useful and can be named as Information.

Data processing results knowledge

Guided and unguided transmission media• Wired or Guided Media or Bound Transmission Media:

Bound transmission media are the cables that are tangible or have physical existence and are limited by the physical geography. Popular bound transmission media in use are twisted pair cable, co-axial cable and fiber optical cable. Each of them has its own characteristics like transmission speed, effect of noise, physical appearance, cost etc.

• Wireless or Unguided Media or Unbound Transmission Media: Unbound transmission media are the ways of transmitting data without using any cables. These media are not bounded by physical geography. This type of transmission is called Wireless communication. Nowadays wireless communication is becoming popular. Wireless LANs are being installed in office and college campuses.

Illustrative chart of guided and unguided media

Conclusions

Reference links• http

://ecomputernotes.com/computernetworkingnotes/communication-networks/what-is-transmission-media-and-types-of-transmission-media

• http://ecomputernotes.com/computernetworkingnotes/communication-networks/describe-the-different-transmission-media

• http://ecomputernotes.com/computernetworkingnotes/communication-networks/twisted-pair

• http://ecomputernotes.com/computernetworkingnotes/communication-networks/write-short-note-on-coaxial-cable

• http://ecomputernotes.com/computernetworkingnotes/communication-networks/write-short-note-on-optical-fiber

• http://ecomputernotes.com/computernetworkingnotes/communication-networks/what-is-wireless-network

• http://ecomputernotes.com/computernetworkingnotes/communication-networks/microwave-transmission

• http://ecomputernotes.com/computernetworkingnotes/communication-networks/microwave-transmission

That is all

Thank you for listening