help in low pass filter design

hi guys ..

I have problem with designing the low pass filter using microwave office ...
the objective is as follow :
return loss 9 db over bassband frequency of 0-2 GHZ
attenuation 20 db at the stop band edge of 3 GHZ
source and load termination 50 ohm
maximum line impedance 90 and minimum is 25
Fabrication materila RT 5880 Duroid .

i started design this filter by using the microwave office . and i started with the lumped element design and i get all the result correct .
then i move to the design in order of high and low frequency . and i got it done ..
then when i moved to the microstrip design i face a problem with the graph which i couldnt get the S11 correctly ... it shows me totally diffrent shape of the graph ....

the microstrip graph is graph 2 ...


and here is the link of the microwave office file ....

Untitled Project.emp


hopefully someone can help and thanks in advance

I didn't download your microwave office file because i'm using ADS, but at high operating frequency the discrepancy between lumped design and microstrip design would be high and it should be noted that the measured results are obviously closer to microstrip result.

I have designed it with iFilter for you...
The design invoice will be mailed later...
Use this...

Edit: I have saved as 8.0 version

thanks Big boss but the file format couldn't run with my microve office .. its seems u r using a new version ... am using 2008 ... can u make it in the 2008 format ? :D
and for the ADS momentum am not using it ... do u have any site to download this software ? thanks again ....

OK, I will try to save as older format.

For ADS. you can download this software from ADS 2011.05 Download - Agilent EEsof EDA Downloads -*Agilent EEsof Documentation Center
You should request a evaluation license but they don't generally give this evaluation license to particulars .Nevertheless, you can download Sonnet Lite ( Free !) from Sonnet Software - EM Analysis and Simulation - High Frequency Electromagnetic Software Solutions and with this free version you can simulate your circuit upto 4 ports and 32MB memory consumption.I think Sonnet is pretty suitable for your application.

tnx alot big boss ... but plz can u show me the steps to get this filter dont ... 1 by one ... tnx

Simple..
I used " iFilter Design Wizard" in MW Office.. Bit it might not be available for you because it has seperate license..

HI
I use CST microwave studio 2009. I think it's very useful to design your filter. you can use the help page of CST