Nov 18, 2012 #1 E elecfan Member level 1 Joined Nov 8, 2012 Messages 34 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,286 Location Earth Activity points 1,571 can we consider AM modulation as multiplication of two signals?
Nov 18, 2012 #2 J jeffrey samuel Advanced Member level 4 Joined Jul 23, 2012 Messages 1,092 Helped 107 Reputation 214 Reaction score 107 Trophy points 1,363 Location chennai,india Activity points 6,373 It is more of super imposition than mere multiplication
Nov 18, 2012 #3 FvM Super Moderator Staff member Joined Jan 22, 2008 Messages 52,422 Helped 14,749 Reputation 29,780 Reaction score 14,101 Trophy points 1,393 Location Bochum, Germany Activity points 298,107 can we consider AM modulation as multiplication of two signals? Click to expand... Clearly yes, see this explanation https://en.wikipedia.org/wiki/Amplitude_modulation Two simple multiplication cases can be distinguished y(t) = [1 + m(t)]*c(t) (regular AM with carrier, as used in broadcast) y(t) = m(t)*c(t) (double-sideband modulation with suppressed carrier)
can we consider AM modulation as multiplication of two signals? Click to expand... Clearly yes, see this explanation https://en.wikipedia.org/wiki/Amplitude_modulation Two simple multiplication cases can be distinguished y(t) = [1 + m(t)]*c(t) (regular AM with carrier, as used in broadcast) y(t) = m(t)*c(t) (double-sideband modulation with suppressed carrier)
Nov 19, 2012 #4 E elecfan Member level 1 Joined Nov 8, 2012 Messages 34 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,286 Location Earth Activity points 1,571 in the first case we will have: y(t) = c(t) + c(t).m(t) (multiplication of the two or convolution?) and also in the second case. in the first case we will have wc, (wc+wm) and (wc-wm) in frequency band and in the second case just wc+wm and wc-wm. is this right?
in the first case we will have: y(t) = c(t) + c(t).m(t) (multiplication of the two or convolution?) and also in the second case. in the first case we will have wc, (wc+wm) and (wc-wm) in frequency band and in the second case just wc+wm and wc-wm. is this right?
Nov 19, 2012 #5 N ninju Full Member level 3 Joined May 14, 2011 Messages 188 Helped 49 Reputation 98 Reaction score 48 Trophy points 1,308 Activity points 2,398 It is multiplication. y(t)=[ 1 + m(t)].c(t) m(t)= cos(2*pi*fm*t) c(t)= cos(2*pi*fc*t) Substituting the above in y(t), and applying a trigonometric identity, you can find terms that contain fc+fm and fc-fm. The purpose of this is to frequency translate the message signal. The way to do it is multiplication.
It is multiplication. y(t)=[ 1 + m(t)].c(t) m(t)= cos(2*pi*fm*t) c(t)= cos(2*pi*fc*t) Substituting the above in y(t), and applying a trigonometric identity, you can find terms that contain fc+fm and fc-fm. The purpose of this is to frequency translate the message signal. The way to do it is multiplication.