Magnetron device with mode converter and related methods

1. A relativistic magnetron with axial extraction, comprising:

a mode converter including a number of cavities defined by N=2(2s+1) where s any positive integer, said cavities extend in an axial direction onto a diffraction output of radiation up to a diameter of an antenna that exceeds the diameter corresponding to a cutoff frequency of a radiated wave in a regular cylindrical waveguide, and said mode converter placed directly within said diffraction output of radiation effectively converts an operating π-mode into a radiated mode of a simpler radiation pattern across a wide band of frequencies and said cavities with the same polarization placed in each azimuthally identical half of the relativistic magnetron with mirror symmetry extend onto said diffraction output providing conversion of said operating π-mode to a TE 11 -mode that is radiated with a radiation pattern approximate to a Gaussian radiation pattern with linear polarization that is parallel to an imaginary line that divides said azimuthally symmetric halves.

2. The relativistic magnetron of claim 1 , wherein said diffraction output of radiation is a conical horn antenna.

3. The relativistic magnetron of claim 2 , wherein all cavities of said mode converter extend onto said conical horn antenna thereby providing a radiation pattern corresponding to the operating wave.

4. The relativistic magnetron of claim 2 , wherein every other cavity of said mode converter extends onto said conical horn antenna thereby providing a radiation pattern that corresponds to a symmetrical TE 01 -mode.

5. The relativistic magnetron of claim 1 , wherein said mode converter includes two diametrically opposite cavities that extend onto said diffraction output thereby providing a radiation pattern that is a narrow wave beam close to a Gaussian radiation pattern.

6. The relativistic magnetron of claim 1 , wherein at least two diametrically opposite cavities are opened directly to an output waveguide to provide conversion of said operating π-mode to said TE 11 -mode without said conical horn antenna.

7. The relativistic magnetron of claim 6 , wherein a radius of said output waveguide is the same as a radius of an anode block comprising of a plurality of cavities that provide the minimal volume of a magnetic field-producing system.

8. The relativistic magnetron of claim 7 , wherein said magnetic field-producing system is a solenoid placed around the relativistic magnetron.