In phase and quadrature components of a signal

What is In phase and quadrature components of a signal????

and how to obtain tat from tat signal??????

Thanks in advance

Hello,

You can describe every sinusoidal signal based on V(t) = A*cos(w*t+phi). At t = 0 the phasor (vector) describing the signal has length of A and has positive angle (w.r.t. x axis) of phi degrees. It rotates with omega (w) radians/s

You can decompose the phasor in its x (In-phase) component and y (quadrature) component.

Icomp = A*cos(phi), Qcomp = A*sin(phi).

So you can describe your signal V(t) = A*cos(w*t+phi) also as V(t) = Icomp*cos(wt) + Qcomp*(-sin(wt) ).

where A = sqrt(Icomp^2+Qcomp^2), and phi = arctan(Q/I)

Check the correct quadrant for arctan. As the quadrature component is 90 degrees in advance over the in-phase component, you need -sin(wt) to get the correct time domain function.

So having two generators 90 degrees out of phase, synchronized and that can be AM (DSB) modulated, enables you to generate every combination of amplitude and phase.

If you have two seperate DSB modulators (ring mixers), RF generator and 90 degr phase shifter, you can also generate every RF signal. you feed the Icomp en Qcomp to the mixers. One mixer (that receives the Icomp) get the RF carrier directly, the other mixer (that receives the Qcomp) via the 90 degr. phase shifter. Just sum the outputs and you have a modulator that can generate every RF signal.