File:AM signals.svg

This shows the variations in the modulated signal with changes in the percentage en:modulation. Created using en:Gnuplot.
The commands are in the following sequence:

# describe the formula (x indicates time)
f(x) = (1 + m*sin(2*pi*100*x))*sin(2*pi*10000*x)
# set the terminal
set terminal svg size 800 600 |dynamic |enhanced
# set the output file
set output "am_signals.svg"
# set the 'default' axes properties 
set xlabel " "
set ylabel "Amplitude"
set grid
unset key
# start multiplot
set multiplot
# 50% Modulation
set origin 0,0.66
set title "50% Modulation"
set size 1,0.33
plot m=0.5, f(x)
# 100% Modulation
set origin 0,0.33
set size 1,0.33
set title "100% Modulation"
plot m=1, f(x)
# 150% Modulation"
set origin 0,0
set size 1,0.33
set xlabel "time"
plot m=1.5, f(x)

# end plotting
unset multiplot
unset output
set terminal win

(Note: The carrier frequency = 10000Hz = 10KHz and modulating signal frequency = 100Hz)

2005-12-28 (original upload date)

Originally from en.wikipedia; description page is/was here.

Original uploader was Krishnavedala at en.wikipedia

Licensed under the GFDL by the author; Released under the GNU Free Documentation License.