[comp.dsp] Hilbert Transforms

steckner@lri.uwo.ca (Michael Steckner) (09/28/90)

Is there anyone who can help me compute a discrete Hilbert Transform?
I understand that I multiply all positive frequency components by +i
and all negative components by -i, but what about the DC frequency bin?

Also, does the input function need to be in the real domain, or can the
input be a complex function.

Thanks

nhanke@iiic.ethz.ch (Norbert Hanke) (10/01/90)

In time domain the Hilbert Transform performs a 90 degree phase shift. Look
at the DC bin as a cosine with zero frequency: phase shifted it will be a
sine with zero frequency, so the DC bin will disapear.
You may use the Hilbert Transform for a complex time function if this
makes sense to you...

Norbert Hanke
ETH Zurich