i don't actually get what you mean by using odd numbers of stub. is that means that i have to apply the stub on each resonator? it's hardfor me to explain my design in words, do you mind giving me your email address so that i can show you my design?
as for the stub, i'm actually replaced the...
i have simulate my 4th order filter design which consists of two half-wave resonators and two quarter-wave resonators, where i have replaced the grounded point of the quarter wave resonator by a stub, but the frequency response doesn't seem to be a 4th order band pass filter, it only have 2...