Question
Explain the terms: (i) Attenuation, (ii) Demodulation used in communication system.
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Answer
Attenuation : The loss of strength of a transmitted signal during its propagation through transmission channel is called attenuation.
Demodulation : For reception and reproduction of audio signal it is necessary to separate them from modulated wave. The process of separating the audio frequency signal from the modulated wave is called demodulation or detection and the device used for this purpose is called demodulator or detector which is also an electronic device. Demodulation is the reverse process of modulation.
Demodulation : For reception and reproduction of audio signal it is necessary to separate them from modulated wave. The process of separating the audio frequency signal from the modulated wave is called demodulation or detection and the device used for this purpose is called demodulator or detector which is also an electronic device. Demodulation is the reverse process of modulation.
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