In amplitude modulation (AM), the phase of the modulating signal can affect the properties of the modulated AM signal. The AM signal is formed by superimposing a carrier wave with a modulating signal, where the amplitude of the carrier wave is varied in accordance with the instantaneous amplitude of the modulating signal.
The mathematical representation of an AM signal is:
SAM(t)=(Ac+Am⋅m(t))⋅cos(2πfct+ϕm⋅m(t))S_{ ext{AM}}(t) = (A_c + A_m cdot m(t)) cdot cos(2pi f_c t + phi_m cdot m(t))SAM(t)=(Ac+Am⋅m(t))⋅cos(2πfct+ϕm⋅m(t))
Where: AcA_cAc = Amplitude of the carrier signal, AmA_mAm = Amplitude of the modulating signal, m(t)m(t)m(t) = Modulating signal (often an audio waveform), fcf_cfc = Carrier frequency, ϕmphi_mϕm = Phase sensitivity of the AM modulation.
The phase sensitivity term (ϕmphi_mϕ<span style="top: -2.55em; margin-left: 0em; margin-right: 0.0