What do real and imaginary parts of a complex signal mean?

[inadaze]

Hey,
I was wondering if anyone could explain to me the meaning of "real and imaginary parts of a complex signal"?

Thanks
Jay

 

[cronxeh]

im going to ignore the signal part..

but in a form of say z = a + ib where i= $$\sqrt{-1}$$

the a is the real part, and
the ib is the imaginary

 

[robphy]

im going to ignore the signal part..

but in a form of say z = a + ib where i= $$\sqrt{-1}$$

the a is the real part, and
the ib is the imaginary

In some textbooks, the "Imaginary Part of z" is defined Im(z)=b, a real number.
So, z=Re(z)+i Im(z).

Using the notation z* for the "complex-conjugate of z"...
To determine Re(z) from z, use Re(z)=(z+z*)/2.
To determine Im(z) from z, use Im(z)=(z-z*)/2i.

 

[inadaze]

laymen

Thanks for your reply.
What I failed to mention was that I have a very low understanding of math. Could you explain that again in laymen terms.

Thanks
Jay

 

[chroot]

If you can provide us some context for where you read this quote, we can probably be more helpful. Normally complex numbers are used to simplify the mathematical treatment of engineering problems, but all physically possible signals are real only.

- Warren

 

[Simfish]

In the complex number system, there are two axes: the horizontal real axis and the vertical imaginary axis. The imaginary part of a number can be ositioned along the imaginary axis.