Filter Design using CAD tool

[gbaerf]

Please tell me the step by step procedure for filter designs
I refered book ludwig RF circuit design ....
and I know the design using standard tables
but dont know the procedure for microstrip filter design

regards/gbaerf

 

[khouly]

frist from the filter response
get the normalized filter elements "low pass prototype"
then transform the prototype to lumped elements value

if u need microstrip filter , transform the lumped elements to tarnsmission lines

caluclute the width and length of the TL then EM simulate the filter


wish this help

khouly

 

[SkyHigh]

If you have HP-ADS, I can help.

In the schematic capture window, place components like inductors, resistors, capacitors that you will need for your filter (HP, LP, BP, BS, etc). Connect these components up, shunt or set input/output nodes for simulation.

In HP-ADS, you can generate
1. Frequency and Phase response in Bode Plot
2. Smith Chart for matching your component values in Z and Y planes

All you need to do from here is to fine tune the values of your components to get the filter response or shaping for the appropriate attenuation, roll-off, ripple, etc.

Hint: Insert resistors and inductors at input and output to model the impedance of the connectors, bonding wires, etc.

Once all this schematic level design is done and you are satisfied, generate netlist.

Select the appropriate technology by importing the type of substrate available in the library for the one you will use for fabrication. You may also specify other parameters or technologies by setting constraints or importing libraries.

Proceed to layout editor to auto-generate the physical components in the layout. HP-ADS can automatically create the components, place and route everything for you.

However you can manually edit to suit your taste.

Goodluck!

Another competitive tool in the market is the RF CAD tools produced by Ansoft Inc.

 

[Manjunatha_hv]

Hi,


One more popular CAD for Filter design is AWR Microwave Office...
It has inbuilt Filter Synthesis tool, which generates Filter Schematic & Layout from the specifications...

Also they support interface to famous Nuhertz Technologies, Nuhertz Filter & also even you can start filter design from scratch...i.e
Lumped Filter design then use the Transmission line Calculator then construct Microstrip filter design finally optimize.....
If it required simulate using EM Simulator...

couple of very good articles available @ the below mentioned link

Go through this paper
A 2.6 GHz Microstrip Hairpin Filter
Design Using CAD and EDA Tools

HFE0304_Imparato.pdf
an191.pdf and
2002MAR01_AMD_EDA_AN.PDF




Good luck...

 

[sbhalerao]

Hi,
I would agree with SkyHigh ... You should use ADS - its the best possible tool for RF design and you would find plenty of filter designs in it. Yu could also do in-depth analysis using the frequency domain... The only problem could be that its got a steeper learning curve... (But shouldn't be so difficult if you have used EDa tools earlier)...
Bye...

 

[boy]

Any tool can design a filter with group delay (phase) constraint?

 

[red-sun]

Anoft Designer has a wizard for filter designing, it is very easy to use.
but if you are designing filters for diplexer, i have no good ideas. maybe someone else can help you on this topics.