RF Filters designing

Hi
I am pursuing my post graduation and i have a doubt about what are the differences between hairpin filter and edge coupled filters?

Hi!

Basically the same, but the resonators in a hairpin filter are bent into a "U" shape in order to use less space.

For the same PCB size the hairpin filter might have better out-of-band rejection if is well designed, but at the expense of slightly higher in-band insertion loss and ripple.
Also hairpin filter has more things to be optimized compared to edge filters (as length, spacing, mittering).
In fact mittering is one of the most important factors that affect the performances of a hairpin filter designed for microwave frequencies.