transmission media ppt Final

Aneri Shah

JanviShah

MihirShah

MuktiShah Payal

Shah

Transmission media Introduction Types of Transmission Media Guided Media1. Twisted Pair cable2. Coaxial Cables3. Optical Fiber Unguided media1. Frequencies2. Infrared3. Microwave4. Radio Waves5. Applications

Topic Included

What is Transmission Media

• Sending data from one device to another is called transmission of data.

• Medium used to transmit the data is called Media.

• Transmission of data through Medium is called Transmission Media.

Types of Transmission Media

TransmissionMedia

Guided(Wired)

Unguided(Wireless)

Twisted-PairCable

Co-Axial Cable

Fibre OpticCable

Microwave Frequencies

Radio Range Frequencies

Infrared Range Frequencies

Guided ( Wired )

• Physical path between transmitter and receiver. • The medium is important in determining the limitations of

transmission.• The transmission capacity, in terms of either data rate or

bandwidth depends critically on the distance.

Twisted Pair

• A twisted pair consists of two insulated copper wires arranged in a regular spiral pattern.

• Twisted pair may be used to transmit both analog and digital transmission. • In the initial stages it was a low-bandwidth medium but now networks

support speed upto 1gbps.• Less expensive and easy to work with.• Eg: Telephone Networks.

Twisted Pair Types

• Unshielded Twisted Pair (UTP)– ordinary telephone wire– cheapest– No protection from

outside interface

• Shielded Twisted Pair (STP)– metal braid or sheathing

reduces interference– more expensive– harder to handle (thick,

heavy)

Coaxial cable

• Coaxial cable consist the followings layers in its construction– The copper conductor– Insulation layer of plastic foam– Second conductor or shield of wire mesh tube or metallic foil– Outer jacket of tough plastic

• Coaxial cable can be used over longer distances and can transmit both analog and digital signals.

• More expensive than twisted wire cables.

Continue…

• Coaxial cable is a versatile transmission medium, used in a wide variety of applications, including:Television distribution - aerial to TV systems.

• Characteristics– Its installation us comparatively simple.– It supports transmission speed upto 10 mbps.– It suffers from data attenuation.

Fiber Optics

• Fiber optic cable is known as most sophisticated cables used in long distance network connection.

• Through this cable data transmission is done through Light ray signal transmission rather than electrical signal transmission.

• It has inner core of glass that conducts light.This inner core is surrounded by cladding.

• Cladding is nothing but layer of glass material that reflects light back into the core.

• Each fiber is then surrounded by plastic Cover

Benefits of Fiber Optics

• Greater speed • smaller size • lower attenuation• Light weight• High data carrying capacity of more

than a billion bits per second• High transmission speed(upto 100

gbps)

Unguided (Wireless)

• Use radio or infrared signals which can travel through air.• Can be used in LANS, MANS and WANS (using satellites and microwave

communication).• Data Transfer depend on ranges of frequencies viz. Radio range

frequencies, Microwave frequencies and Infrared Range frequencies.

Wireless Transmission Frequencies

• 1GHz to 40GHz (Microwave Frequencies)– highly directional– Satellite communication

• 30MHz to 1GHz (Radio Range Frequencies)– Omni directional– broadcast radio– Don’t require dish shaped antennas

• 3 x 1011 to 2 x 1014 (Infrared Range Frequencies)– Local– Used in remotes of electronic instruments

Infrared

•Allows computing devices to communicate via short-range wireless signals.

•Computers can transfer files and other digital data bidirectionally.

•Are blocked by walls unlike Wi-Fi and bluetooth.

•No licenses required for usage.

•Used in remote controls of electronic devices.

•Very short range (not more than 5 metres).

Microwave Waves

• Have lower frequency than radio waves.• The frequency is in the range of 1GHz-40Ghz.• The most popular applications of microwave waves are bluetooth and

radar.• GPS devices, microwave ovens and radio astronomy also use

microwave waves.• Also used in WANS.

Radio Signals

• The frequency is in the range of 30 MHz to 1 GHz.• Have a longer wavelength than infrared lights.• Used in mobile communication, broadcasting, radar and other navigation

systems, satellite communication, computer networks and innumerable such devices.

• It also has its application in the medical industry.

Wi-Fi

WiFi or Wireless Fidelity refers to the technology surrounding the radio transmission of internet protocol data from an internet connection wirelessly to a host computer.

Wi-Fi

•Wi-Fi is one of the most important examples of wireless data transmission.•Wi-Fi can be found at a number of places like college campus, business units, airports hospitals etc where a user can connect to the wi-fi connection and use internet.•It uses radio signals to transfer data.•Security is a very important aspect of wi-fi connections.•Many cities like london are planning for city wide wi-fi by the year 2012.

Bluetooth

Bluetooth is a low-cost, low power, short range wireless communication technology used in networking, mobile phones and other portable device. Bluetooth wireless technology also enables devices to communicate with each other as soon as-they come within range; no need to connect, plug into, install, enable or configure anything.

Benefits of Bluetooth

•Possible to connect to the Internet on a dial-up connection through mobile phone. Surfing the Internet then becomes possible anywhere your mobile phone can connect to your internet service provider.•Perhaps you prefer to use a traditional mouse with your laptop. Choose a Bluetooth-enabled mouse and you won’t have to keep track of a mouse cable.•Transfer of data •Bluetooth mobile devices and earphones.