[ Reply | Next | Previous | Up ]
From: Andreé / DD3LY
Date: 05 Feb 2002
Time: 06:42:11
Remote Name: 195.145.17.185
Hi David, my range of interest is only from 2 to 30MHz, so if I use lumped elements in SMD-size I do NOT have to worry about stray elements (C and L) especially if I rethink HOW to build the rf-circuit over a ground plane.
There are programs existing, by which an impedance represented by a certain Smith diagram can be matched in a specified frequency range up to a specified VSWR-tolerance-range. These programs do this matching in a kind of iterative process. These programs have a simple or even a multistage matching circuit as a result. This depends on the dimesions of the source (the antennas smith diagramm) and the dimensions of the goal (frequency range and VSWR range).
But these programs are NOT what I am looking for. I do NOT want to match over a certain frequency range. What I am looking for is somehow the same, but just the other way round: I want to rebuild the antennas impedance over the specified frequency range by lumped R,L and C elements. This AGAIN will be calculated in a kind of iterative process, perhaps first started with some kind of intelligent try-and-error-process, which is often used if I have more unknown elements than known elements to find out which way to start to obtain a convergend result.
Maybe the first mentioned programs for matching an antenna do not run on a PC, even not if it is a really modern one. But this is NOT a problem for me! My problem is to find someone who wrote such a "matching-an-antenna-over-a-wide-frequency-range"-program to discuss with him how to rewrite such a programm to get the "lumped antenna circuit" as a result.
The fact that the one is possible should make the other possible too, doesn't it?
With greetings from Germany
Andreé