Modulating and Demodulating 

Modulating and Demodulating are a pair of signal processing methods that are used in signal amplify and transmit. For example, we can modulate two voice by different frequency and transmit them by one line, then demodulate them by their carry frequency.
Java Learning Program
Modulating and Demodulating 
1.Input Frequency(0<F<2500Hz), Amplitude(0<A<5) and Phase(0<P<360) of the signal» 
2.Press "Generate" to produse the signal and to compute its spectrum.
3.Press "Mul. Off/On" to open/close modulate function.
3.1 Press "Reset" to clear the signal
3.2 Generate a low frequency signal
3.3 Generate a high frequency signal to modulate the low frequency signal.
3.4 Generate the high frequency signal again to demodulate the modulated signal.
3.5 Press "Low Pass" to remove high frequency components.