Coherent Superposition of Electric Fields?

whitenight541

Hi all,

What's the meaning of coherent superposition?

Can it be used to sum up several electric fields of the same frequency but with different phases possibly having different directions?

Each Electric field is represented as Ei = Eo e ^ -(j k ri) U(theta i, phi i)
where U(theta, phi) is a direction vector
Since each Ei has a different ri i guess they have different phases.

If yes, how can I do this?

If no, what are the other alternatives?

thanks in advance :)