Because of the high maintenance needed to monitor and filter spammers from the RF Cafe Forums, I decided that it would
be best to just archive the pages to make all the good information posted in the past available for review. It is unfortunate
that the scumbags of the world ruin an otherwise useful venue for people wanting to exchanged useful ideas and views.
It seems that the more formal social media like Facebook pretty much dominate this kind of venue anymore anyway, so if
you would like to post something on RF Cafe's
page, please do.
Below are all of the forum threads, including all
the responses to the original posts.
Post subject: PCB detector circuit
Unread postPosted: Mon Sep 06, 2004 5:47 am
Joined: Mon Sep 06, 2004 5:43 am
I am new to Rf design, and have to design PCB layout for a detector circuit
using a voltage doubler configuration.
I am simulating using MIcrowave Office and simulating my matching circuit (double open stub).
1) I'm a bit stumped with the results of my simulation in terms of S parameters. They dont seem to change much, even when I remove or place a 100pF capacitor in parallel with load.
2) Am unsure about designing my microstrip matching element in PROtel. Any tips on this?
Unread postPosted: Wed Sep 08, 2004 3:32 pm
We're going to need a little more information.
- What frequency range is the detector working in?
- What is the impedance of the detector?
- What kind of substrate are you using?
- Are you using S-parameter files for the discrete components being modeled, or mathematical models from the simulator?
All these can explain the small change with or without the 100 pF capacitor.
Regarding impedance matching, MWO should provide libraries of impedance transformer topologies, then the optimizer should take care of tuning.
Post subject: detector circuit
Unread postPosted: Tue Sep 14, 2004 11:43 pm
I am using a voltage doubler configuration using Schottky HSMS 8202 from Agilent. I am planning to use it at 900MHz
Im planning to use two different materials, FR4 and ROdgers duroid 5880, Er=2.2
Im using MWOffice's SPice model of diode to model 8202 schottky, using Agilent supplied Spice parameters. Is this sufficient to model the diodes in MWOffice, or should I be doing more?
I have been using the optimizer to vary the length of the stubs to obtain the best S11 and S22 values from linear simulator. Is this appropriate?
Any help would be great as I am a complete newbie to this area and a desperate undergrad