An SSB-AM signal is generated by modulating an 800 kHz carrier by the signal m (t) = cos 2000nt +2 sin 2000nt. The amplitude of the carrier is A. = 100. 1. Determine the signal îm (t). 2. Determine the (time-domain) expression for the lower sideband of the SSB-AM signal. 3. Determine the magnitude spectrum of the lower-sideband-SSB signal.

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Q 2 :J An audio signal given by 15sin(4000pi * t) + 20sin(8000pi * t) amplitude modulated(DSB-FC) a sinusoidal carrier wave 60sin(100, 000pi * t) a. Derive an expression for the modulated signal. b. Find the modulation index. c. Find the spectrum of the modulated signal. d. Sketch the spectrum of the modulated signal e. Which type of demodulation method you propose to reconstruct the audio at receiver. Why? to

A sequence of alternating 1s and 0s is transmitted as a square wave. What is the fundamentalfrequency and how many harmonics can be used if the available BW is 100 MHz and a data rate of 56Mbps is desired? Express the signal as a mathematical function of time (s(t)) and sketch the resultingsignal in both the time and frequency domains. Is this a “good enough” representation of the squarewave? Why or why not?