Modulation

Modulation is a process that alters the characteristics of a carrier wave according to information in the message signal to generate a modulated wave that is transmitted. Modulation Toolkit VIs are capable of analyzing carrier waveforms with amplitude, phase, or frequency modulation.

The unmodulated carrier is represented by the following equation:

v(t) = A_ccos(ω_ct + θ)

The amplitude-modulated carrier signal is represented by the following equation:

v(t) = (m(t) + A_c)cos(ω_ct + θ)

The frequency-modulated carrier signal is represented by the following equation:

v(t) = A_ccos((m(t)+ω_ct)+ θ)

The phase-modulated carrier signal is represented by the following equation:

v(t) = A_ccos(ω_ct + θ + m(t))

where m(t) is the time-varying modulation, A_c is the amplitude of the carrier wave, and ω_c is the frequency of the carrier wave.