microstrip bandpass filter

hi guys, I need to deal with a project regarding an ultra-small microstrip bandpass filter with a new type of capacitive coupled resonator.The filter should be 2 times smaller compared to the smallest known filter of the same class. The filter is designed for high frequency range (Ku band 12-18GHz), therefore the resonant frequency and bandwidth should be in this range. The microstrip used is the Duroid substrate (er = 4.5). Preferably the filter should be designed in a square-shaped form to minimize the space required.Hope you guys could help with some information which would be benefitial for the project.Thank you

Try the book by Inder Bahl, Prakash Bartia

or this book "Microstrip filters for RF/microwave applications".
This is by a guy called Lancaster. You can also search for articles on him. He and his group makes a lot of compact filters.

Regards

The filter should be 2 times smaller compared to the smallest known filter of the same class.

Click to expand...

Mind sharing with us, what is the rough dimension of your filter that you wish to achieve at the end? What is the rejection that's required for your filter?

Mike Lancaster sent me a copy of his book when he published it. It is really good. Wish I had had it back when I was designing filters. Highly recommended.

the dimension of the filter should be around 27-30 mm2. I searched for some journals and articles from the IEEE site and I found a relevent article. I'm attaching the pdf file here. However the design in it is made with a resonant frequency at 5.3GHz,lower cut-off frequency at around 5GHz and upper cut-off frequency at 6.0GHz. The objective of my design is that the resonant,lower and upper cut-off frequency should be in the Ku band (12-18GHz).I tried varying the parameters of the lumped components designed in the article and it just affects the bandwidth while the resonant frequency remains at 5.3GHz. Please kindly have a look at the file and help me solve the problem.Thanks alot in advance.For your info,I'm using ADS(Advanced Design System) as a simulation tool.