Design of coaxial Bragg reflectors

A coaxial line periodically loaded by circular disks on the inner conductor is specifically designed to act as Bragg reflector to prevent radio-frequency fields from leaking out of a 6.6-GHz monotron. Design criteria to ensure a stopband as wide as possible are presented and a discussion is given on how band gap width, center frequency, and reflectivity arise from the geometry of the periodic structure