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Techopedia explains Telecommunications




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UNIT 3. MEANS OF TELECOMMUTING

Part 1. MODERN MEANS OF TELECOMMUNICATIONS

The single biggest problem in communication is the illusion that it has taken place.”George Bernard Shaw

LEAD IN

Examine the pictures above. What can they say about the modern ways people communicate?

Examine the pictures showing modern means of telecoms. How have they influenced and changed our life? What are these devices used for? Select a picture witch has made our lives more difficult.

smartphone laptop with touchscreen tablet
e-book fiber optics satellite

3. Compare the four modern telecom means and electronic devices with their prototypes. Grade them from 1(bad) till 5(excellent) according to the following criteria:


· price

· effectiveness

· drawbacks

· speed of data transmission

· convenience

· popularity


  conventional telephone mobile telephone   books e-books
  letters e-mail   face to face communication social networking

§ READING and VOCABULARY

Study the following words in the box. Make sure you know them. Try to explain each notion.

transmitter medium analogue repeater
receiver wire digital to amplify
transceiver carrier wave frequency attenuation
circuit modulation switches voltage

Read the text and translate it into Ukrainian.

Techopedia explains Telecommunications

Telecommunications is also known as telecom. Telecommunications is a universal term that is used for a vast range of information-transmitting technologies such as mobile phones, land lines, VoIP and broadcast networks.

Telecommunications refers to the exchange of information by electronic and electrical means over a significant distance. Telecommunications devices include telephones, telegraph, radio, microwave communication arrangements, fiber optics, satellites and the Internet.

A complete, single telecommunications circuit consists of two stations, each equipped with a transmitter and a receiver. The transmitter and receiver at any station may be combined into a single device called a transceiver. The medium of signal transmission can be electrical wire or cable (also known as "copper"), optical fiber or electromagnetic fields. The free-space transmission and reception of data by means of electromagnetic fields is called wireless.

Data is conveyed in a telecommunications circuit by means of an electrical signal called the carrier or carrier wave. In order for a carrier to convey information, some form of modulation is required. The mode of modulation can be broadly categorized as either analog or digital. Analog modulation such as that used in radio broadcasting is an amplitude modulation. The oldest form of analog modulation is amplitude modulation (AM), still used in radio broadcasting at some frequencies. Digital modulation actually predates analog modulation; the earliest form was Morse code. During the 1900s, dozens of new forms of modulation were developed and deployed, particularly during the so-called "digital revolution" when the use of computers among ordinary citizens became widespread.

A communications network is a collection of transmitters, receivers, and communications channels that send messages to one another. Some digital communications networks contain one or more routers that work together to transmit information to the correct user. An analog communications network consists of one or more switches that establish a connection between two or more users. For both types of network, repeaters may be necessary to amplify or recreate the signal when it is being transmitted over long distances. This is to combat attenuation that can render the signal indistinguishable from the noise. Another advantage of digital systems over analog is that their output is easier to store in memory, i.e. two voltage states (high and low) are easier to store than a continuous range of states.

3. Answer the following questions:

1. What is telecommunication?

2. What does communication circuit consist of?

3. What is transceiver?

4. What is amplitude modulation? Where is it used?

5. What are the communications network elements?





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