Carrier1 = cos ( 2*pi*fc1*t1) where fc1 = 160,000 Hz
Carrier2 = cos ( 2*pi*fc2*t2) where fc2 = 320,000 Hz
Carrier3 = sin ( 2*pi*fc2*t3) where fc2 = 320,000 Hz
s(t)=x1 cos(𝜔1*t) + x2 cos(𝜔2*t) + x3 sin(𝜔2*t)
Perform demodulation with phase shift 10, 30, 90 degrees.
Carrier1 = cos ( 2*pi*fc1*t1 + (phase_shift_angle* pi) / 180 )
Carrier2 = cos ( 2*pi*fc2*t2 + (phase_shift_angle* pi) / 180 )
Carrier3 = sin ( 2*pi*fc2*t3 + (phase_shift_angle* pi) / 180 )
In phase shift 10: Signal 1: there is very little attenuation in it ( the sound is slightly lower). Signal 2 & 3: there is very little interference between them, but the signal with the current corresponding carrier is the one with the higher sound.
In phase shift 30: Signal 1: there is more attenuation in it ( the sound is lower than the previous case). Signal 2 & 3: there is more interference between them, and the signal with the current corresponding carrier is still a little bit with higher sound.
In phase shift 90: Signal 1: it is completely attenuated ( there is no sound). Signal 2 & 3: there is complete interference between them, the signals are interchanged with each other ( when we try to get signal 2, we get signal 3 and vice versa).
Perform demodulation with a local carrier frequency that is different by 2 Hz and 10 Hz from its carrier frequency (frequency shift).
Carrier1 = cos ( 2*pi*(fc1+2)*t1 )
Carrier1 = cos ( 2*pi*(fc1+10)*t1 )
Different by 2Hz: There is little attenuation and distortion in the output signal.
Different by 10Hz: There is more attenuation and distortion in the output signal than the previous case.
For more figures and explanation, check the attached pdf.
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