What Is the Signal's Form and Duration from Its Complex Power Spectral Density?

[Spalding215]

Homework Statement

"The complex power spectral density is :

S(jw)=(1/(w*(w^2+a^2))*e^j90

Find the form and duration of the signal."

Homework Equations

Any ideas on how to solve this ?[/B]

The Attempt at a Solution

What I've managed to calculate so far is:
http://tinypic.com/r/zydamr/9

 

[rude man]

Never heard of a complex power spectral density.