Jan, it is a while that my book about signal theory is closed, but I would think that the shape of your pulses enters linearly, and as a deterministic component of the signal. As such I think you may just multiply your PSD by the power spectrum of the filter that degrades your ideal signal to the real one. Or, in time domain, convolute the two respective autocorrelation functions. Equivalently, you may directly multiply your pulse-shape power spectrum bye the PSD of the aleatory dirac's train. Hope this is helpful. Luca On Wed, 30 Jan 2002 14:44:41 +0100 "Jan Vercammen" <jan.vercammen.jv1@xxxxxxxxxxxxxxxx> wrote: > > hello si-list (communication engineers), > > > I was wondering if someone knows a reference (article, paper, book, ...) > where the power spectral density > of a random digital signal with finite rise-fall time is described. It is > easy to find information on ideal random > digital signals. Here ideal means "with ideal steps" or unit-steps. > > The ideal case is easy to calculate using the Wiener-Khichine theorem which > states that the autocorrrelation > function and the power spectral density form a fourier transform pair. > Ideal digital pulses have a triangular > autocorrelation function, but I was wondering what it would be if the > pulses have a finite rise-fall time. The > autocorrelation function would be "triangular-like", but is it possible (1) > to describe it analytically and, if so, > (2) is it possible to calculate it's fourrier transform? > > > thank you, > > Jan Vercammen > EMC/PCB engineer > Agfa-Gevaert NV, Belgium > > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field > > or to administer your membership from a web page, go to: > //www.freelists.org/webpage/si-list > > For help: > si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field > > List archives are viewable at: > //www.freelists.org/archives/si-list > or at our remote archives: > http://groups.yahoo.com/group/si-list/messages > Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > -- Luca Giacotto <lgiacott@xxxxxxxxx> ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu