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Complex FIR Filters

Started by NiCad June 24, 2006
Hello DSPers,

After reading the thread about "Why cplex filters" a question comes to
mind: how to generate complex filter coefficients if i do not wish to
apply desired phase and amplitude correction to the original signal?

I've passed the initial real signal through a Hilber Transformer, and have
thus a complex analytic signal. I'm using a Blackfin DSP, and it has a
complex fir function, as well as a real fir function.

I am wondering: if i simply use the same coefficients for both the real
and complex parts of the complex filter, will it yield the same result as
if i pass both parts of the signal individually through a real filter, and
reassemble the signal into I and Q after filtering?

Sorry if this seams a bit simple, but I haven't found much explanations on
complex FIR filters. Anyone have an equation for these type of filters? and
for complex fir coeff generation? (actually a generalised equation about
transorming filters into complex filters would be awsome)

btw, this forum really is awsome. Some guys on here are blowing my mind in
how they really have their heads wrapped around the subjects they talk
about! Keep up the awsome forum, and the super neat answers!

NiCad