The signal m(t) = 2 cos(4000) is used to modulate a carrier c(t) = 100 sin(2x fet), with frequency f. = 100kHz. is Determine and sketch the spectrum of the modulated signal s(t), if the modulation performed a) (10pts) DSB-SC, b) (10pts) AM with amplitude sensitivity ka-0.25,

a) A Double-Sideband Amplitude Modulator is shown in fig. 1 V DC cos(2n x 2 x 105t) m(t) v,(1) Σ Figure 1

In a Frequency Modulator, the carrier signal, ec=8 sin[27(500k)t] is frequency modulated by em=5cos[2n(1k)t]). The Frequency deviation constant of the modulator is K= - 800 Hz/V. Determine: a. Frequency deviation at t=145µsec b. Frequency deviation at t-360usec c. Maximum frequency deviation d. Modulation index of the FM signal e. Equation of the modulated signal f. Instantaneous frequency of the FM signal at t=283usec g. The percent modulation if the modulated signal is for FM broadcast

kindly explain this part ,, how sinc100t is represemted in frequency domain

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