Extended interaction output circuit using modified disk-loaded waveguide

An extended interaction output circuit for interacting with a modulated electron beam and for outputting RF electromagnetic energy, said circuit comprising:

• a first cylindrically-shaped linear cavity having an associated diameter and width;
• a second cylindrically-shaped linear cavity respectively having a diameter greater than and a width less than the diameter and width of said first linear cavity and a first disk adjoining said first and said second linear cavities, said first disk having a first hole permitting transmission of said electron beam between said first linear cavity and said second linear cavity;
• a third cylindrically-shaped linear cavity respectively having a diameter greater than and a width less than the diameter and width of said second linear cavity and a second disk adjoining said second linear cavity and said third linear cavity, said second disk having a hole permitting transmission of said electron beam between said second linear cavity and said third linear cavity, said second hole having a size greater than said first hole;
• and
• a fourth cylindrically-shaped linear cavity having a third disk adjoining said third and fourth linear cavities, said third disk having a third hole having a size greater than said second hole;
• wherein, said cavities act as an RF filter having successively tapered impedances.

An extended interaction output circuit for interacting with a modulated electron beam and for outputting RF electromagnetic energy, said circuit comprising:

• a plurality of linearly disposed cavities having an axially extending beam tunnel for permitting the traveling therethrough of said modulated electron beam and for coupling therethrough said electromagnetic energy between successive ones of said cavities;
• and
• a plurality of annular disks each having a single respective hole providing said beam tunnel, each of said disks respectively separating adjacent ones of said cavities;
• wherein, relative proportional dimensions of successive ones of said holes and of successive ones of said cavities generally increases in steps along an axial extent of said circuit.

A method for interacting with a modulated electron beam and outputting RF electromagnetic energy, said method comprising the steps of:

• focusing said modulated electron beam through a plurality of linearly disposed cylindrically-shaped cavities via a beam tunnel axially extending therethrough, said cavities each having an associated diameter and width;
• coupling said RF electromagnetic energy between successive ones of said cavities via said beam tunnel;
• and
• successively tapering impedances of said cavities to reduce reflections of said RF electromagnetic energy.