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3. Translate the following word-combinations and memorize them.

Mobile phone, emergency service, central base, mobile unit, individual user, cellphone network, radio transceiver, main switching centre, weak signal, period of silence.

4. Match the beginnings of the sentences in a with their endings in b.

A

B

  1. Mobile units do not usually communicate directly …

  2. Mobile phones can be moved, …

  3. Each cell is allocated …

  4. In the network, the same frequencies can be used for many ..

  5. When a call is made to a cellphone, the MSC …

  6. All the base stations for a cluster of cells are …

  7. The size of the cells varies …

  1. different telephone calls at the same time.

  2. permanently connected to a main switching centre.

  3. first checks the signals to contact each cellphone.

  4. between 1 km to about 30 km across.

  5. but they must stay within fixed area.

  6. a number of frequency channels for communication.

  7. with other mobile units.

5. Choose the correct variant.

1. All communications take place through a central contral base with …

  1. tel-n system;

  2. radio system;

  3. mobile phone systems.

2. Mobile units send messages to …

  1. their users;

  2. control base station;

  3. subscribers.

3. The problem of lack of suitable … can be overcome by using a cellphone network.

  1. VHF frequencies;

  2. Number of users;

  3. Phone models.

… frequencies can be used in cells further away without causing interference.

  1. different;

  2. the same;

  3. opposite.

  1. MSC contains a computer … suitable frequencies and control the communications for that cluster of the cell.

  1. to receive;

  2. to transmit;

  3. to select.

  1. Answer the following questions about the text. Decide which paragraphs are most likely to contain answers to these questions.

  1. Who uses mobile phones?

  2. What does the MSC register of cellphones contain?

  3. What is the difference between a mobile phone and a cellphone?

  4. Why is a cellphone called a cellphone?

  5. How large is a cell?

  6. How does the MSC prevent interference due to too strong a signal level?

  7. What’s the best number of cells to form a cluster?

  8. When were radiophones developed?

  9. How does an MSC ensure that a cellphone is using the right frequency for a call?

  10. What is the MSC permanently connected to?

7. Study these statements about making a cellphone call. Link them into longer sentences. You may omit words and make whatever changes you think are necessary in the word order.

  1. A call is made from a cell phone.

  2. The cellphone scans the available frequencies.

  3. The cellphone finds the strongest signal to the nearest base station.

  4. The cellphone detects that the base station is idle.

  5. The cellphone transmits the required dialing code.

  6. If the code is received….

  7. ……the base station sends a signal back to the cellphone.

  8. The signal indicates a suitable frequency channel for the call.

  9. The cellphone tunes to the allocated channel.

  10. The cellphone user hears the ringing tone.

  11. The call is answered.

  12. The user can speak and listen using the cellphone, as with a normal phone.

  13. The call is finished.

  14. The cellphone signals to the base station.

  15. The cellphone sends a short burst of signal at 8 kHz.

  16. If the code is not received….

  17. ….. the cellphone abandons the call.

  18. ….. the cellphone tries again later.

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