Communication Communication technologiestechnologies

Technology 3 ESOTechnology 3 ESO

IndexIndex WhatWhat isis communicationcommunication?? WhatWhat are are thethe mainmain componentscomponents ofof communicationcommunication

?? WhatWhat kindskinds ofof communicationcommunication technologiestechnologies existexist?? CommunicationCommunication signalssignals GuidedGuided communicationcommunication Non Non guidedguided communicationcommunication: : electromagneticelectromagnetic

spacespace TelephoneTelephone: : ConmutationConmutation andand mobilemobile phonesphones RadioRadio TelevisionTelevision GPSGPS InternetInternet

What is communication?What is communication?

Communication is a proccess in which two Communication is a proccess in which two or more agents interchange informationor more agents interchange information

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Elements of CommunnicationElements of Communnication

Emisor, who produces the message and sends itEmisor, who produces the message and sends it Receiver: who receives the messageReceiver: who receives the message

(emisor and receiver often interchange roles during (emisor and receiver often interchange roles during the communiaction proccess)the communiaction proccess)

Message: information sent from one to anotherMessage: information sent from one to another Channel: The form of interchanging information. Channel: The form of interchanging information.

i.e: radio, press, TV, telephony…i.e: radio, press, TV, telephony… Medium: the physical which information flows Medium: the physical which information flows

through. i.e: paper, space, wires…through. i.e: paper, space, wires…Index

Classification of communication Classification of communication TechnologiesTechnologies

Communication Communication technologies are often technologies are often classiffy according to classiffy according to the medium in:the medium in:

Guided: They use a Guided: They use a material medium such material medium such as electric wires, as electric wires, optical fiberoptical fiber

Non guided: the Non guided: the information is carried information is carried in waves thoruogh the in waves thoruogh the spacespace

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Communication signalsCommunication signals

Communication sisgnals can be:Communication sisgnals can be: Analogic: Which can have whatever Analogic: Which can have whatever

value in a rangevalue in a range Digital: which are coded binary and Digital: which are coded binary and

can be proccessed by a computer.can be proccessed by a computer.

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Guided communicationGuided communication In guided communication, In guided communication,

information flows thorough information flows thorough material elements: electric material elements: electric wires, optical fibrewires, optical fibre

Before being send, Before being send, communication is transformed communication is transformed into electric or optic signals.into electric or optic signals.

Electric wires: Much cheaper but Electric wires: Much cheaper but suffers from interference and suffers from interference and atenuation (the signal weakens atenuation (the signal weakens with distance). i.e: telephony, with distance). i.e: telephony,

Optic fibre: much more Optic fibre: much more expensive and delecated but expensive and delecated but doesn’t suffer from interferences doesn’t suffer from interferences or atenuation: ADSL, digital TV or atenuation: ADSL, digital TV

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Non guided communicationNon guided communication In non guided communication, In non guided communication,

communication flows through communication flows through the space in the form of the space in the form of electromagnetic waves. electromagnetic waves.

Radioelectric spaceRadioelectric space (spectrum) is the whole range (spectrum) is the whole range of frequencies or wavelengths of frequencies or wavelengths of electromagnetic waves: it of electromagnetic waves: it is divided in different regions: is divided in different regions: gamma, X, ultarviolet, visible, gamma, X, ultarviolet, visible, infrared, microwave and infrared, microwave and Radiofrecuencies (RF): the Radiofrecuencies (RF): the most usual communications most usual communications use from IR to RFuse from IR to RF

Terrestrial anthens and Terrestrial anthens and satellites are used to send, satellites are used to send, repeat and receive repeat and receive information. information.

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TelephonyTelephony Telephony consists of interchanging Telephony consists of interchanging

acustic signals beetween an emisor and a acustic signals beetween an emisor and a receptor who interchange their roles. receptor who interchange their roles. There are two kinds of telephony :There are two kinds of telephony :

Conmuted grid: telephones terminals are Conmuted grid: telephones terminals are connected to a guided grid. A node system connected to a guided grid. A node system provides a guided way to connect the two provides a guided way to connect the two terminals in communication.terminals in communication.

Mobile phones are connected by satellites Mobile phones are connected by satellites which receive their signals and sends them which receive their signals and sends them signals from other terminals. They can signals from other terminals. They can also connect to the conmuted grid also connect to the conmuted grid through speciphic devices. Last generation through speciphic devices. Last generation mobiles have turned into small/powerful mobiles have turned into small/powerful multifunction devices with a powerful multifunction devices with a powerful microproccessor insidemicroproccessor inside

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RadioRadio

In radio, sound signals In radio, sound signals flow in form of waves flow in form of waves from an emisor to a from an emisor to a receiver, both having receiver, both having anthens.anthens.

Radio has only one Radio has only one direction, the emisor direction, the emisor and the receiver do and the receiver do not interchange their not interchange their rolesroles

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TelevisionTelevision

In television, audio and images are sent from an In television, audio and images are sent from an emisor to a receiver in the form of waves emisor to a receiver in the form of waves (anthens) or by a wire (TDT). (anthens) or by a wire (TDT).

There are different technologies to produce There are different technologies to produce images in an screen_(plasma, RCV, LCD) images in an screen_(plasma, RCV, LCD) Index

GPS (Global positioning system)GPS (Global positioning system)

GPS was invented by the GPS was invented by the USA’s armyUSA’s army

A GPS uses a system of 8 A GPS uses a system of 8 or more satellites and a or more satellites and a terrestrial receiver. terrestrial receiver.

The receiver and at least The receiver and at least three satellites interchange three satellites interchange signals. The time it takes signals. The time it takes to the signal to trip to the signal to trip between them gives the between them gives the receiver know the receiver know the distance. Taking three distance. Taking three signals of distance at the signals of distance at the same time, the receiver same time, the receiver works out its position in works out its position in the earth’s surface.the earth’s surface.

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InternetInternet Internet is a worldwide system of Internet is a worldwide system of

interconected computers which interconected computers which interchange information. There are interchange information. There are different ways of connecting to the different ways of connecting to the internet (transmmision protocols)internet (transmmision protocols)

TCP-IP: Where information is divided TCP-IP: Where information is divided into small packages (TCP) and sent into small packages (TCP) and sent from a server (computer) to a client from a server (computer) to a client computer.computer.

P2P (peer to peer), where it doesn’t P2P (peer to peer), where it doesn’t exist a client-server jerarchy. exist a client-server jerarchy. Computers share their hardware Computers share their hardware resources acting as servers or clients resources acting as servers or clients at the same time.at the same time.

Several devices are used to connect to Several devices are used to connect to the internet: modems, routers. Todays the internet: modems, routers. Todays computers, PDA’s provide their on computers, PDA’s provide their on anthen to connect via wi-fianthen to connect via wi-fi

A specific software (explorers) are A specific software (explorers) are used to interchange information.used to interchange information.

Internet provides many different Internet provides many different utilitis such as e-mail, information utilitis such as e-mail, information (web pages), news, telephony, (web pages), news, telephony, videoconferences, virtual market, etcvideoconferences, virtual market, etc

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