newbie question to DSP and frequency domain

[echoangel9111]

Hello,

I see some textbook representation of frequency using X(jw) and some other cases X(w). Can someone clarify this

 

[Jack// ani]

Well...jw is complex/imaginary freq term whereas w is real one!!

 

[claudiocamera]

I trully believe that it is a question of notation, try to figure out if the both representantion regards to the frequency domain of the signal ( Its fourier representation) if so, dont worry about each author choose his way to present the subject.

 

[weng]

I think X(jw) consists of only imaginary freq term wheras X(w) may consist of both real and imaginary elements.

 

[MSGHP]

X(jw) is the frequency response of x(t). X(w) can be the same or it might be simple notatin of X(e^jw) that is the frequency response of x[n] ( discrete time signal).