microstrip combline bandpass fiter

hi my specs abt the design of combline bandpass filter is ripple in passband is 1db and bandwidth is 20MHz and centre frequency is 1.8GHz and attenuation on stop band is 60dB at 1.88GHz . manually i designed first coupled line filter when i implementing that coupled line filter in ADS iam not getting ripples in pass band and my centre frequency is shifting to left .plz help me in this aspect and how to design and implement that coupled fitler into combline bandpass filter via hole grounding using microstrip in ADS ..............

U WORK USING DEFECTED GROUND STRUCTURE OR U FILTER IN STRIP LINE

hi,

use DESIGN GUIDE (Passive Circuits) in ADS software

1. select coupled line component
2. Enter the specifications
3. click on Design All in Desing Assistant tab
4. update the schematics in Layout and make momentum simulation

there will be a shift in the passband w.r.t specs.

Adjust the specifications to get the required band in momentum simulations


You can also try with Hairpin Structure in ADS


regards
Chandregowda H