# Get I and Q components from a signal (multple frequency signal)?

Is there anyway to get the I and Q components from a signal in the time domain? The signal has multiple frequencies.

So far I have been doing this in a SIMPLE situation:

• Fast fourier transform to get each frequency and each frequencies amplitude and phase
• Then use $$\cos(\textrm{phase}) \cos(2 \pi f \times \textrm{time_vector}) - \sin(\textrm{phase}) \sin(2 \pi f \times \textrm{time_vector})$$ for each frequency.
• This gives me I and Q data for each frequency, then I just need to sum them to getback the original signal.

Problem is, I am trying to do something more complex and need to get the I and Q data straight from the time domain signal without following the above steps. Where I is In phase component & Q is Quadrature phase component of the signal.

• What do you mean by I and Q components? – Jonas Schwarz Jul 23 '18 at 9:37
• How do I turn a real time domain signal into IQ data – Natalie Johnson Jul 23 '18 at 21:51