SYMMETRICAL TROUGH WAVEGUIDE ANTENNA ARRAY

• US 3,653,054 A
• Filed: 10/28/1970
• Issued: 03/28/1972
• Est. Priority Date: 10/28/1970
• Status: Expired due to Term

• Current Assignee: Cheng Paul Wen
• Original Assignee: Cheng Paul Wen
• Inventors: Wen, Cheng Paul
• Primary Examiner(s): Lieberman, Eli
• Application Number:
  US05/084,821
• Time in Patent Office: 517 Days
• Field of Search: 343/772,777,778,754,854,787 333/21R
• US Class Current: 343/772
• CPC Class Codes: H01Q 13/20 Non-resonant leaky-waveguide or transmission-line antennas; Equivalent structures causing radiation along the transmission path of a guided wave
• CPC Class Codes: H01Q 3/443 varying the phase velocity along a leaky transmission line frequency scanning H01Q3/22; non-resonant leaky-waveguide or transmission-line aerials H01Q13/20

Abstract

A symmetrical trough waveguide antenna array is provided wherein a section of trough waveguide has spaced radiating mode conversion portions. Each of the radiating mode conversion portions includes a member of gyromagnetic material spaced between the center fin and one of the side walls of the trough waveguide and a member of dielectric material spaced between the center fin and the opposite side wall. When an appropriate DC magnetic field is applied to the gyromagnetic member, signals propagating in one direction along the trough waveguide are converted from the even to the odd mode and consequently radiation of some of the signals occurs at the spaced portions of the waveguide. The section of trough waveguide further includes phase shifter portions. Each of the phase shifting portions includes a pair of members of gyromagnetic material with one of the pair between the center fin and one side wall and the other of the pair between the center fin and the side wall opposite the one side wall. When appropriate DC magnetic field bias is applied to the pair of gyromagnetic members associated with the phase shifter portion, a difference in phase occurs between the spaced radiating mode converting elements.

Claims

1. A trough waveguide antenna array comprising:

a trough waveguide section having longitudinally extending conductive side walls spaced by a longitudinally extending conductive bottom wall with a shorter conductive center fin symmetrically disposed between said side walls and extending from said bottom wall to form a first trough between the center fin and a side wall and a second trough between the center fin and the opposite side wall, said walls and spacing being arranged so that upon the application of electromagnetic signal waves to said section over a given range of frequencies said section is capable of supporting said signals in the even and odd modes, means for coupling said electromagnetic signal waves into and out of said waveguide section, a plurality of radiating mode converting elements, each of said radiating mode converting elements comprising at least one member of gyromagnetic material positioned in a portion of said first trough and at least one other member of dielectric material positioned in a portion of said second trough adjacent to said member of gyromagnetic material, said member of gyromagnetic material and said member of dielectric material being arranged so that upon the application of an appropriate DC magnetic field of a first value to said radiating mode converting element said electromagnetic signal waves propagate along that portion of said section including said element in the even mode and upon the application of an appropriate DC magnetic field of a second value to said radiating mode converting element said electromagnetic waves propagate along that portion of said section including said element in the radiating odd mode, control means for selectively providing said first and second values of said DC magnetic field to said plurality of radiating mode converting elements to provide a desired far field radiation pattern.

2. The combination claimed in claim 1 including means for controlling the phase of said signal between each of said radiating mode converting elements.

3. The combination claimed in claim 2 wherein said phase control means includes a plurality of phase shifting elements wherein each phase shifting element comprises a first and second member of gyromagnetic material with a first member positioned in a portion of said first trough and a second member in an adjacent portion of said second trough.

4. The combination claimed in claim 3 wherein said phase shifting means is spaced between each of said radiating mode converting elements.

5. The combination claimed in claim 3 wherein said first and second members of gyromagnetic material of each of said phase shifting means is spaced below the respective gyromagnetic and dielectric members of each of said radiating mode converting elements.

6. The combination claimed in claim 3 above wherein said phase control means includes means for providing selected values of DC magnetic bias to said members of gyromagnetic material of said phase shifting means to change the steering angle of said radiation pattern.

7. The combination claimed in claim 1 above wherein said side walls of said trough waveguide are exponentially tapered.

8. The combination claimed in claim 1 wherein said trough waveguide includes a dielectric body formed in a manner to cause one surface of said body to define the two side walls, the ridge between said two side walls and with a thin film of conductive material covering said one surface defining the ridge, the bottom wall and side walls.

9. The combination claimed in claim 8 wherein said dielectric body has portions below the region of said first trough to in cooperation with said member of gyromagnetic material of said radiating mode converter element, and said conductive film provide a closed magnetic flux path loop.