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Signal m(t) (shown above) is used to modulate a carrier Acos⁡(2πfct) (where fc ≫ 1000 Hz) using the following 3 modulation schemes: a-DSB-SC b-DSB with Carrier (modulation index μ = 0.5) c-DSB with Carrier (modulation index μ = 2) i. Write an expression of the modulated carrier and plot it versus time for each case ii. Calculate the power efficiency for each case (hint: cos2⁡θ = 0.5(1+cos⁡2 θ) ) iii. If the modulated carrier is applied to an envelope detector, plot the output signal versus time for each case. Comment about the suitability of the envelope detector for each case

Signal m(t) (shown above) is used to modulate a carrier Acos⁡(2πfct) (where fc ≫ 1000 Hz) using the following 3 modulation schemes: a-DSB-SC b-DSB with Carrier (modulation index μ = 0.5) c-DSB with Carrier (modulation index μ = 2) i. Write an expression of the modulated carrier and plot it versus time for each case ii. Calculate the power efficiency for each case (hint: cos2⁡θ = 0.5(1+cos⁡2 θ) ) iii. If the modulated carrier is applied to an envelope detector, plot the output signal versus time for each case. Comment about the suitability of the envelope detector for each case

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Signal m ( t ) (shown above) is used to modulate a carrier A cos ⁡ ( 2 π f c t ) (where f c ≫ 1000 H z ) using the following 3 modulation schemes: a-DSB-SC b-DSB with Carrier (modulation index μ = 0.5 ) c-DSB with Carrier (modulation index μ = 2 ) i. Write an expression of the modulated carrier and plot it versus time for each case ii. Calculate the power efficiency for each case (hint: cos 2 ⁡ θ = 0.5 ( 1 + cos ⁡ 2 θ ) ) iii. If the modulated carrier is applied to an envelope detector, plot the output signal versus time for each case. Comment about the suitability of the envelope detector for each case

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