For ground wave transmission, size of antenna l should be comparable to wavelength of the signal

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communicationsystem

#1

Give reasons for the following:
(i) For ground wave transmission, size of antenna l should be comparable to wavelength of the signal
(ii) Audio signals, converted into an electromagnetic wave, are not directly transmitted.
(iii) The amplitude of a modulating signal is kept less than the amplitude of a carrier wave


#2

(i) To radiate the signals with high efficiency.
(ii) Because they are of large wavelength and power radiated by antenna is very small .
(iii) It is done to avoid making over modulated carrier
wave. In that situation, the negative half-cycle of the modulating signal is dipped and distortion occurs in reception.