Hi there, i was just playing around with the modulation function on Matlab here are the simple commmands I run: � t = 5; � t=0:0.01:10; � y=power(sin(pi*t/(2*T)), 0.5); � mod = modulate(y, 250, 44100, 'am'); � plot(t, mod) so I wanted to know what I should choose my sampling frequency to be - right now it is set to 44100, but how do I know this is appropriate? When I plot (t,mod), it seems that it is very dependent on the sampling frequency. Try my commands out yourself and you will see what I mean, but can someone explain to me why this is such an issue? I woudl have thought that as long as my sampling frequency was greater than 2*fc (where fc in this example is set to be 250) then it wouldnt matter if I set my sampling frequency to be at something much greater than the nyquist rate like 44100 or 88200 for example; but plotting: � mod = modulate(y, 250, 44100, 'am'); gives me a much different graph than plotting: � mod = modulate(y, 250, 88200, 'am'); I just dont understand theoretically, if someone could explain it owuld be great! thank you!!! -LD This message was sent using the Comp.DSP web interface on www.DSPRelated.com

# AM modulation

Started by ●July 30, 2005

Reply by ●July 30, 20052005-07-30