Relativistic magnetron using a virtual cathode

Patent metadata

Field	Value
Publication number	US-10192709-B2
Application number	US-201715829278-A
Country	US
Kind code	B2
Filing date	Dec 1, 2017
Priority date	Jun 17, 2014
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

The present invention provides a relativistic magnetron including an anode with an entrant channel, the channel having an input end, an output end and a dimensional discontinuity between the ends. The channel is connected to the magnetron and has an anode defining an interaction space located between the dimensional discontinuity and output end. Also provided is a cathode, located upstream, a spaced distance away from the interaction space towards the input end, the cathode is adapted to send an electron beam into the interaction space where the electron beam forms a virtual cathode in the interaction space.

First claim

What is claimed is:

1. A relativistic magnetron comprising:
an anode with an entrant channel, said channel having an input end, an output end, said channel having a first region and a second region, said first region in communication with said second region and having a smaller radius than said second region, said first and second regions forming a dimensional discontinuity at the location where said channel changes from said first region to said second region, said dimensional discontinuity located between said input and output ends of said channel;
said channel connected to the magnetron anode defining an interaction space located between said dimensional discontinuity and said output end;
a cathode located upstream a spaced distance away from said interaction space towards said input end, said cathode adapted to send an electron beam into said interaction space;
said electron beam forms a virtual cathode in said interaction space; and
a magnetic mirror configured to suppress axial electron beam leakage current.

2. The relativistic magnetron device of claim 1 wherein said channel is cylindrical and said first region has a smaller radius than said second region.

3. The relativistic magnetron device of claim 2 wherein said first region is connected to said second region.

4. The relativistic magnetron device of claim 1 wherein said cathode is externally located with respect to said second region and inside said entrant channel.

5. The relativistic magnetron device of claim 2 wherein said cathode is externally located with respect to said second region and inside said channel.

6. The relativistic magnetron device of claim 5 wherein said dimensional discontinuity creates a space limiting current that is less than the current of the electron beam.

7. The relativistic magnetron device of claim 6 wherein said dimensional discontinuity creates a space limiting current, I b , by configuring said magnetron as follows:

I
b

=

I
0

⁢

(

Γ
-

γ
b

)

γ
b

⁢

γ
b
2

-
1

2
⁢

⁢
ln
⁢

⁢

(

R
a

R
c

)

where

I
0

=

mc
3

e

≈

17
,
000
⁢

⁢
Amperes

,

Γ=1+eU/mc 2 , γ b =−0.5+√{square root over (2Γ+0.25)}, m is the electron mass, e is the electron charge, c is the speed of light in vacuum, R c is the radius, R a is the radius of the second region, and U is the electrostatic potential of the anode.

8. The relativistic magnetron device of claim 1 wherein said cathode is externally located with respect to said channel.

9. The relativistic magnetron device of claim 8 wherein said dimensional discontinuity creates a space limiting current, I SCL , by configuring said magnetron as follows:

I
SCL

=

I
0

⁢

(

γ

2
/
3

-
1

)

3
/
2

1
+

2
⁢

⁢
ln
⁢

⁢

(

R
a

R
b

)

where

I
0

=

mc
3

e

≈

17
,
000
⁢

⁢
Amperes

,

R a is the radius of the second region, where R b is the radius of the electron beam, and U is the electrostatic potential of the anode.

10. The relativistic magnetron device of claim 8 wherein said dimensional discontinuity creates a space limiting current, I SCL , by configuring sa

Assignees

• Stc Unm

Inventors

• Schamiloglu Edl
• Fuks Mikhail I

Classifications

• H01J23/20

  Cavity resonators; Adjustment or tuning thereof · CPC title

• H01J25/50 Primary

  Magnetrons, i.e. tubes with a magnet system producing an H-field crossing the E-field (with travelling wave not moving completely around the electron space H01J25/42; functioning with plural reflection or with reversed cyclotron action H01J25/62, H01J25/64) · CPC title

• H01J23/02

  Electrodes; Magnetic control means; Screens (associated with resonator or delay system H01J23/16) · CPC title