Bandpass signals To transmit a baseband signal s(t through a bandpass channel at some center frequency f, we multiply s(t by a sinusoid with that frequency m(t)=Sm(t)Cos(2ft) Amg(t) Cos(lift) Cos(2Tft F[COS(2+)]=((ff)+(f+f)2Bandpass signals • To transmit a baseband signal S(t) through a bandpass channel at some center frequency fc, we multiply S(t) by a sinusoid with that frequency Sm(t) Um(t)= Sm(t)Cos(2πfct) = Amg(t) Cos(2πfct) Cos(2πfct) F[Cos(2πfct)] = (δ(f-fc)+δ(f+fc))/2 Eytan Modiano -fc f Slide 8 c