Hello Mark, because Eric's book is so beautifully written, I've gone through it almost twice already. However, it has very little or nothing to do with my question. I also went through Johnson's book (Advanced Black Magic), Silvester and Benedek?s publications on discontinuties and quite a lot of other electromagnetic texts. So, it's not a question for beginners. Jose recommended me Gupta's book (thanks Jose), which I already read. Here, Wolf and Mehran's waveguide model are used to analyze T-bends, Gap and other discontinuities, but the questions on how far the excited modes go away from the discontinuity and how this depend on the frequency are not dealt with. As far as I know, this subject has not being properly dealt with yet. So may the gurus recommend any other publications on this subject or some advice. Thanks, Charles --- Mark Burford <Mark_Burford@xxxxxxxxxxx> wrote: > Suggest you start with Eric Bogatin's book 'Signal > Integrity Made Easy' > like I did (also a post graduate) then save the > questions you have after > reading the book for these guru's of the signal > integrity world. It is > an excellent book and a good read also. > > Anyone else go to the Cadence seminar Tuesday that I > didn't get to meet? > > I was the younger looking of you 'seasoned' > experts!! ;o) > > Hope this helps > Mark > > -----Original Message----- > From: si-list-bounce@xxxxxxxxxxxxx > [mailto:si-list-bounce@xxxxxxxxxxxxx] > On Behalf Of Charles Harrington > Sent: 12 May 2005 11:36 > To: si-list@xxxxxxxxxxxxx > Subject: [SI-LIST] Discontinuities on PCB > > Hello, > > When a TEM (or quasi-TEM) signal propagating on a > microstrip trace meets a discontinuity (e.g., a via) > on a substrate at microwave frequencies, > higher-order > modes are excited at the discontinuity, leading to > reflections. > > Can anyone tell me exactly what kind of modes are > excited and why they are excited. How far away from > the discontinuity can they propagate and how does > this > depend on the operating frequency. > > I'm a postgraduate student currently working on=20 > discontinuities on PCB. My search for relevant > literature led me to this list. So, I'll appreciate > any > help.=20 > > Charles. > > > =09 > Yahoo! Mail > Stay connected, organized, and protected. Take the > tour: > http://tour.mail.yahoo.com/mailtour.html > > ------------------------------------------------------------------ > 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: =20 > //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 > =20 > > ------------------------------------------------------------------ > 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 > > > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ------------------------------------------------------------------ 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