Sending Information

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!



Modern technology allows users of mobile phones to send text messages, images, and messages .

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There are many different types of mobile phones. Some phones allow group meetings and discussions to be held. Other mobile phones also allow conferencing to take place.

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Using mobile phones when driving to send or receive information is in certain countries. This can be dangerous and be the cause of accidents.

Sending images requires a large amount of information to be processed. Images consist of individual , or dots.

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There are three different types of pixels: red, , and blue. There are also 256 difference intensities. A typical images on a mobile phone will consist of over 300, 000 pixels. Each pixel consists of bits. The of the internet connection will control how long it takes for an image to be sent.

There are distinct advantages of sending information using digital technology. Digital transmission provides the user with a clear transmission, where it is less likely for interference and to be picked up in transmission. A special technique knows , removes unnecessary information and allows less bits to be transmitted. A typical type of compression is JPEG, where speeds of transmission can be greatly by selecting the of compression. Too much compression is not good, and it can affect the of the image.


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Images are also transmitted sent by TV stations. Digital TV needs to use compression because of the amount of that needs to be transmitted. To save bandwidth only the which have changed from one frame to the next are sent.

Satellite TV broadcasts use information sent by signals from satellites in orbit above the . These satellites are at such an altitude that they appear to be stationary to the user on Earth. These orbits are known as orbits. Microwaves have high . This allows more to be available so that higher quality images can be sent.

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The signals are normally received by a aerial. A special decoder is needed to the signals.