Hi, Ma: If your 2-port structure is electrically short, you can take the Z(1,1) and calculate Y = 1 / Z(1,1) where the Y is not Y(1,1). Then, you can find C as: C = Im(Y) / omega Best regards, ---------------------------------------------------------------------------- Jian X. Zheng, Ph.D., Zeland Software, Inc. 48834 Kato Road, 103A, Fremont, CA 94538, U.S.A. Tel: 510-623-7162, Fax: 510-623-7135 ---------------------------------------------------------------------------- > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] > On Behalf Of ma mu > Sent: Wednesday, January 25, 2006 3:36 PM > To: si-list@xxxxxxxxxxxxx > Subject: [SI-LIST] Capacitance > > Hi all, > > Thanks . I have another question for you. I am creating a model with > Ansoft designer and I need to find out my transmission line capacitance . > Ansoft designer can not calculate the capacitance directly . But can give > S,Y and Z parameter. there is a equation where capacitance could be find > out with any of those parameters, I believe Y parameter. But I forgot the > equation. I was looking at my High speed book but could not find it !!! > any help would be appreciated. > > Ma > "Jian X. Zheng" <jian@xxxxxxxxxx> wrote: > Hi, Ma: > > No, I think it is different. |S11| = - 3 dB means |S11| is about 0.707 or > |S11*S11| = 0.5 or 50% of the power is reflected. If there is little > metallic, dielectric and radiation losses (normally the case unless for > antennas), the |S21| should be 0.707 or |S21*S21| = 0.5 or 50% of the > power > is transmitted. > > Regards. > > -------------------------------------------------------------------------- > -- > Jian X. Zheng, Ph.D., Zeland Software, Inc. > 48834 Kato Road, 103A, Fremont, CA 94538, U.S.A. > Tel: 510-623-7162, Fax: 510-623-7135 > -------------------------------------------------------------------------- > -- > > > -----Original Message----- > > From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] > > On Behalf Of ma mu > > Sent: Wednesday, January 25, 2006 2:17 PM > > To: si-list@xxxxxxxxxxxxx > > Subject: [SI-LIST] -3dB at S21 graph > > > > Hi all, > > > > In my insertion loss, S21 graph, I got -3dB loss at 1.5 Ghz. My question > > is : > > transmission at 1.5 Ghz is 50% or 70% ? I thnik 50% . please give > > me feedback. > > > > Ma > > > > > > > > --------------------------------- > > Bring words and photos together (easily) with > > PhotoMail - it's free and works with Yahoo! Mail. > > > > ------------------------------------------------------------------ > > 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 FAQ wiki page is located at: > > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > > > > List technical documents are available at: > > http://www.si-list.org > > > > 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 > > > > > > > > --------------------------------- > Bring words and photos together (easily) with > PhotoMail - it's free and works with Yahoo! Mail. > > ------------------------------------------------------------------ > 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 FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > > List technical documents are available at: > http://www.si-list.org > > 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 FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org 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