Electron multipacting can cause loss of the the field level in resonat
ors or it can break the high power rf components like couplers and win
dows. This phenomenon starts if certain resonant conditions for electr
on trajectories are fulfilled and if the impacted surface has a second
ary yield larger than one. A general cure against multipacting is to a
void the resonant conditions. Therefore, we investigated the dynamics
of the electron trajectories in order to find rules for these resonanc
es. We developed new computational methods which combine the standard
trajectory calculations with advanced searching and analyzing methods
for multipacting resonances. In numerical experiments we consider diff
erent coaxial structures. We are able to find those rf incident power
levels at which the multipacting occurs and, thereafter, to locate and
identify different multipacting processes. We characterize multipacti
ng behavior in straight and tapered lines, and for the straight coaxia
l line we give simple scaling laws for the multipacting power bands wi
th respect to the diameter, impedance and frequency. Furthermore, the
present analysis method turns out to be a powerful tool for optimizing
different methods to suppress multipacting. Here, in particular, the
biasing DC voltage method is considered.