Dear SI-Listers, imagine the following situation: +-----------------------------+ o---| |--- C ---+ 50 Ohm | "Optimum" Matching Network | | o---| |--- R ---+ +-----------------------------+ An RC series element should be matched to 50 Ohm over all frequencies from 0 to infinity (or whatever is possible). Question: --------- What is the upper limit of (passive) matching? In other words, how good can the "optimum" matching network be if we are clever enough to find it? Answer: ------- I have come the following formula in a text book (supposed to be from Bode): Integral 0-infinity of (2*pi*ln (1/r) df) <= pi /RC The formula gives an upper limit for the integral of the reflection coefficient r over all frequencies f from 0 to infinity. Now my questions to you: ------------------------ 1. My text book does not explain or derive the formula. Do you have more detailed references? 2. What is the corresponding formula for an LR network, for an LRC network, for an arbitrary network? 3. Have you ever made use of that formula? Any input is very much appreciated! Regards, Christian Schuster IBM ------------------------------------------------------------------ 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