Low Pass Filter and Fourier Transforms

[Natalie89]

What is the general Fourier Transform for a low *** filter if the lowpass filter also has a bandwidth of W Hz, and fc >>W,?

I think it would this:

∂(fc) + ∂(f-fc) + ∂(f-fc)

 

[rootX]

Just a rectangle between -W and W with height 1.

It is represented in form similar to rect (f/W)

 

[Natalie89]

Thank you so much!