Re： bandpass filter and awr ...

hi guys

im working on microwave bandpass filter using awr microwave office
i worked on center frequency = 6ghz using fr4 substrate and as we knw its very lossy material. i just wanted to practice on .

now the substrate available is fr4 so i ill go for 1.6 ghaz
i tried to calculate the lower n upper frequencies
which they are upper =2.4, and lower = 0.8 ghz

i used the wizards in microwave office and by choosing the coupled line method bt it says ''an umexpexted COM exception occured during schematic generator

and i dont unerstand why ?

anyone recommending hairping method to design the filter bt needs loots of calculations ?

and im not sure about the elements function when we wants to change them from the original circuit ? the junction n bends and how do we decide which one is better for our design and why ?

PS:
check the attachment plz

Hello,

Yes, FR4 is not good for your High Frequency filter.. Try alumina (Er 9.8)...

There are good books on Filter Design & also synthesis works with AWR Microwave Office...

Text book:

J.-S. G. Hong and M. J. Lancaster, Microstrip filters for

RF/microwave applications, John Wiley & Sons, Inc.,

2001.

• References:

G. Mattaei, L. Young, and E. M. T. Jones, Microwave

filters, impedance matching networks, and coupling

structures, Artech House, Norwood, MA, 1980.


• Filter Synthesis Software

Nuhertz Filter Solutions
http://www.filter-solutions.com/passive.html

It also interfaces to Sonnet Lite Free Electromagnetic Simulation software for your
distributed filter simulation...
http://www.sonnetsoftware.com/products/lite/index.html

hello

first, thanks aloot for passing by my topic

but i would like to comment on ur answer,
i tried simulating with changing the conductor material from copper to alumina and it did work with changing the junctions from the default setting


i still want to use fr4 coz its only one that is available to build it on .

i ill try to play around with the circuit n hopes get some good results

many thanks .. and waiting for more comments

I would have to agree that FR4 should be avoided for most filters design. Its too lossy and too variable.

There are quite a few inexpensive laminates available such as Taclam TLC and TLE series which will give much better results.

Here is an article on how to design printed filters using AWR/MWO: http://www.rfshop.co.uk/PrintedFilters.doc

For the lowest loss filters, metals such as brass and aluminium (preferably silver plated) and air are the materials of choice!
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hi...i would like to ask..can i make a modify to my bandpass filter layout such as to crop their shape by using AWR?