how to decide a filter structure by poles and zeros

[amicloud]

filter poles rejection

I am studing a paper of A.E.williams,<a four cavity elliptic waveguide filter>
IEEE MTT-18 p1109. From a elliptic function,he transformed the lowpass prototype
to a bandpass filter and got the power-transmission ratio equation,the equation shows that there are four poles and two finite zeros on either side of the pass band
.then he concluded that:"the poles can be established by four-coupled cavities and the zeros by coupling energy directly from the first to the last cavity".
I am confused on this .Anyone can explain it clearly?thanks!!

 

[accutemicro]

filter poles and zeros

We can offers Ceramic Bandpass Filters(also called dielectric filters, or dielectric ceramic filters,microwave ceramic filters) in standard resonator sizes of 2mm , 3mm , 4mm , 5mm , 6mm , 8mm , 10mm and 12mm (normally 3mm , 4mm , 5mm , 6mm , 8mm ).
Bandwidth: 0.5% to 8% of center frequency
Basic rules of ceramic band-pass filters and diplexersp
The higher the Q-factor of a resonators/band pass filters,the better electrical performance for insertion loss.
The more dielectric resonators combined together for a band pass ceramic filters, the better rejection/attenuation/stopband will be.
Determinant factor for Insertion Loss
Q factor of a resonator, the bandwidth of a filter, and the number of resonators Determinant factor for Attenuation/rejection
The number of resonators, connection type of resonators

**broken link removed**