Miniaturized all-metal slow-wave structure

A miniaturized all-metal slow-wave structure, comprising:

• a circular metal waveguide;
• and a plurality of metal electric resonance units provided in said circular metal waveguide;
• wherein said circular metal waveguide has an inner diameter of no longer than ⅓ free space wavelength of an electromagnetic wave operating at a center frequency;
• wherein said inner diameter of said circular metal waveguide is 0.15-0.25 said free space wavelength of said electromagnetic wave operating at said center frequency;
• each of said metal electric resonance units provided in said circular metal waveguide comprises a ring-shaped electric resonance metal plate with an electron beam tunnel provided on a center thereof, and a ring plate body of said ring-shaped electric resonance metal plate has two auricle-shaped through-holes symmetrically aside an axial-section;
• a main body of every auricle-shaped through-hole is a ring-shaped hole, two column holes extending towards a center of a circle of said ring-shaped hole are respectively provided at two ends of said ring-shaped hole;
• ring-shaped electric resonance metal plates are perpendicular to an axis of said circular metal waveguide and are provided inside said circular metal waveguide with equal intervals there between, external surfaces of said ring-shaped electric resonance metal plates are mounted on an internal surface of said circular metal waveguide.