An amplitude modulated signal is given by V(t)=10[1+0.3cos(2.2×104)]sin(5.5×105t). Here t is in seconds. The sideband frequencies (in kHz) are, [Given (a) 1785and 1715 (b) 892.5 and 857.5 (c) 89.25 and 85.75                                                      (d) 178.5 and 171.5

Question ID - 50293 :- An amplitude modulated signal is given by V(t)=10[1+0.3cos(2.2×104)]sin(5.5×105t). Here t is in seconds. The sideband frequencies (in kHz) are, [Given (a) 1785and 1715 (b) 892.5 and 857.5 (c) 89.25 and 85.75                                                      (d) 178.5 and 171.5

3537

V(t)=10+cosAsinB]

=10+[sin(A+B)−sin(A−B)]

=10+[sin(57.2×104t) −sin(52.8×104t)]

=57.2×104=2πf1

F1==9.1×10−4

≈91 KHz

f2=

≈84 KHz

Side band frequency are

f1=fc −fw=≈85.00 KHz

f2=fc+fw=≈90.00 KHz

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