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(a) Draw 150% and 200% DSB+C AM modulated signal with proper labeling. Calculate the efficiency for a DSB +C AM signal which has both the modulation indices as stated above. [4+2] (b) In the figure below, x(t) = sin⁡ωct is the given signal and ωc = 20 k. It is sampled with a train of pulse signal s(t)¯, where T = 20 μs. The sampled version of the signal is y(t). Sketch the spectrum of X(ω), S(ω) and Y(ω). [6] (c) How can you reconstruct x(t) from y(t) ? Draw with proper block diagram and labeling. [3]

(a) Draw 150% and 200% DSB+C AM modulated signal with proper labeling. Calculate the efficiency for a DSB +C AM signal which has both the modulation indices as stated above. [4+2] (b) In the figure below, x(t) = sin⁡ωct is the given signal and ωc = 20 k. It is sampled with a train of pulse signal s(t)¯, where T = 20 μs. The sampled version of the signal is y(t). Sketch the spectrum of X(ω), S(ω) and Y(ω). [6] (c) How can you reconstruct x(t) from y(t) ? Draw with proper block diagram and labeling. [3]

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(a) Draw 1 5 0 % and 200 % DSB+C AM modulated signal with proper labeling. Calculate the efficiency for a DSB + C AM signal which has both the modulation indices as stated above. [ 4 + 2 ] (b) In the figure below, x ( t ) = sin ⁡ ω c t is the given signal and ω c = 20 k . It is sampled with a train of pulse signal s ( t ) ¯ , where T = 20 μ s . The sampled version of the signal is y ( t ) . Sketch the spectrum of X ( ω ) , S ( ω ) and Y ( ω ) . [6] (c) How can you reconstruct x ( t ) from y ( t ) ? Draw with proper block diagram and labeling. [3]

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