Question
Explain the role of modulation.
✓
Answer
- Low frequency signals cannot be transmitted over large distances. Because of this, a high frequency wave, called a carrier wave, is used.
- Some characteristic (e.g. amplitude, frequency or phase) of this wave is changed in accordance with the amplitude of the signal. This process is known as modulation.
- Modulation also helps avoid mixing up of signals from different transmitters as different carrier wave frequencies can be allotted to different transmitters.
- Without the use of these waves, the audio signals, if transmitted directly by different transmitters, would have got mixed up.
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