This formula violates Causulity. Right way to do this is L = L external + L internal where L internal = Hilbert[Rac(w)] Hilbert[Rac(w)] is Hilbert transform of Rac(w), w=2*pi*f H[Rac(w)]equals to Rac(w) convolution with 1/(pi*w) --- On Fri, 6/27/08, Saoer Sinaga <saoer.sinaga@xxxxxxxxx> wrote: > From: Saoer Sinaga <saoer.sinaga@xxxxxxxxx> > Subject: [SI-LIST] conductor losses > To: si-list@xxxxxxxxxxxxx > Date: Friday, June 27, 2008, 6:04 AM > Hi all, > Some approximate the resistance of a conductor with the > following formula R( > f ) = R_DC + R_AC*sqrt( f ). But I read some where, > R_AC*sqrt( f ) violates > the causality and passivity. > > I also found a formula to approximate the conductor loss of > a plane R( f ) = > R_DC + sqrt( j * 2 pi * f * mu / sigma). > Question: Can I also use the same formula for e.g. via ? > > many thanks, > Saoer Sinaga > NXP > > > ------------------------------------------------------------------ > 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 technical documents are available at: > http://www.si-list.net > > 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 ------------------------------------------------------------------ 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 technical documents are available at: http://www.si-list.net 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