hi can anyone,provided me based concept on radial stub?i am using ADS to simulate.i have tried to search a lot of book in library but still couldnt find relevent topic.
Radial stub is born to realize a "short circuit" at the point where it's placed.
Because in planar circuits a true short require an extra work (i.e. metalizzed via hole), a way that not require via hole is preferred.
A λ/4 open stub realize a short, but it's narrowband.
The Radial stub is a λ/4 open stub with wider bandwidth.
Keywords:
- at connection point, Width shoud be small
- At the open end, Width shoud be wide
- At open end, corners should be avoided (reduce charge accumulation due to point effect), so here's why it's rounded.
The length of the stub includes the pointed end which overlaps the main transmission line. Here is a very old free program to get you in the right ballpark.
A radial stub is analyzed on the basis of radial transmission line theory. This is performed in cylindrical coordinates. I seem to recall reading it in Jordan and Balmain (EM Theory text book). It should also be in Harrington (Time Harmonic Fields text book, look in the chapter on cylindrical coordinates). The radial transmission line modes are writen in terms of Bessel functions. If you are comfortable with Bessel functions, the theory is very easy to understand.
Hello
I am also interested in designing microstrip radial stubs to replace via hole.
The probleme is that I don't have access to the articles mentioned before of sorrentino and march and I didn't find it on edabord. If anyone has the papers or a link I would be thankful.
Here are the references I am searching for
A new simple and accurate formula for microstrip radial stub, Sorrentino et al
Planar circuit analysis of microstrip radial stub, Giannini et al
anyone can supply this paper?
H. Atwater, “The design of the Radial Line Stub: A Useful Microstrip Circuit Element”, Microwave Journal, November 1985, p. 149-156
thanks
I can't find it with internet.
Thanks very much
Hy there,
i' working on a amplifier, and the biasing networks I have chose are radial stubs.. I use these web page to design the stub " **broken link removed** ". I work's grate on the simulation, but i still can't find the equation for Zi. If i find it i'll post it. :evil:
Well people.... The sad thing is that the formula is not simple at all!!, but the good one is that I 'm leaving here a pdf where you'll find it. Hope it helps you anyway.