Question

3(a) A complex signal given by the expression cos (9t x 103t) Vm(t) %3D 0.5cos(Зл х 103t) + сos(8т х 103t) + is used to amplitude modulate a carrier signal, Vc(t) = 3cos(2n shown in Figure 3(a) 105t) as X Vm(t) 0.5cos(3t x 103t) cos(8T x 103t) AM Modulator AM Signal cos(9t x 10t) Vc(t) 3cos(2n x 105t) Figure 3(a) The AM signal in Question 3(a) is developed across 2.2 kn load resistance The modulated carrier in Question 3(a) is filtered to transmit the upper side band (USB) for SSB-SC transmission. State the most appropriate type of filter to be used. Sketch the frequency spectrum of the SSB-SC signal, indicating clearly the amplitudes and frequencies of all the signal (i) (ii) components. Determine the bandwidth of the SSB-SC signal. (iii) (iv) State one advantage of using SSB-SC over the conventional AM transmission зэ

Answer 1

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we con use a bomd Pas Jilter alow a Single bonel uSB. UPpis treaueney 100+4.S 1o45K2. upes tsequtny 100+45 104-5 KM2 Lowes tre= 100-4f 95.4 KH2 104. too -1oy s -100 + 100 954 -954

The bendeuicth 2- B WE :2t=955 KHz to lous ky 2 d 1o4-5- 955 2 9 KH2 s1A e aeduy 4he ome unnecensu element