TRAVELLING-WAVE TUBE WITH PERIODIC MAGNETIC FOCUSING SYSTEM Russian patent published in 1997 - IPC

FIELD: microwave devices including O-type travelling-wave tubes with periodic magnetic focusing system. SUBSTANCE: tube has transist-time channel region of periodic magnetic focusing system built up of axially magnetized annular magnets and pole shoes made of nonretentive material. At least part of focusing system arranged upon introduction of high-frequency energy is built up of abutting sections. Each section has at least three magnets unidirectionally magnetized in axial direction. Magnets of every two adjacent sections are of opposite polarity. EFFECT: improved path of current flow due to increase in effective focusing value of magnetic field. 6 dwg