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O.J.
Mar20-09, 03:55 PM
1. The problem statement, all variables and given/known data

Evaluate the average signal power of the complex signal x(t) = e ^ jwt

2. Relevant equations



3. The attempt at a solution

I know how to solve this but I have a couple of questions on why we have the take the magnitude of the complex signal in the integral? Besides, does a complex signal mean anything in reality? because the way I figured it is complex analysis is just a mathematical tool to help us analyse sinusoidal signals and a signal is always a real or an imaginery part of a complex function (e ^ jwt) and cant be both.

And as such I tried evaluating the integral of e ^ jwt from 0 to To using two ways:

1. write the exponential e ^ jwt in terms of cos and j sin then square that to give cos^2 wt +j2cos (wt) sin (wt) - sin^2 wt where it evaluates to some finite value
2. square the funciton so it becomes e ^ j 2wt and write that in terms of cos and j sin where it evaluates to 0

this is too mathematical I know, but how come the two mathematically valid manipulations yield integrals with different values?

O.J.
Mar21-09, 01:32 AM
bump

O.J.
Mar21-09, 02:57 PM
y am i being ignored?