WIDE-ANGLE PLANAR-BEAM ANTENNA ADAPTED FOR CONVENTIONAL OR DOPPLER SCAN USING DIELECTRIC LENS

• US 3,795,002 A
• Filed: 12/18/1972
• Issued: 02/26/1974
• Est. Priority Date: 12/18/1972
• Status: Expired due to Term

• Current Assignee: ITT Corporation (ITT, Inc.)
• Original Assignee: Jeffrey T. Nemit
• Inventors: Nemit, Jeffrey T.
• Primary Examiner(s): Lieberman, Eli
• Assistant Examiner(s): Punter, Wm. H.
• Application Number:
  US05/316,240
• Time in Patent Office: 435 Days
• Field of Search: 343/754,854,876,16D,18M
• US Class Current: 343/754
• CPC Class Codes: H01Q 19/062 for focusing
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence

Abstract

An antenna involving a plurality of vertical-array-excited parallel-plate coordinate converters feeding a dielectric lens in the shape of a partial toroid. Each corresponding element of the array feeding each parallel-plate coordinate converter is fed in parallel through a wave guide feed arrangement from a Doppler line feed or phased array feed. The radiated beam shape tends to hold its focus and, therefore, has uniform width in elevation over the full azimuth beam width at all useful elevation beam positions.

Claims

1. An antenna system for radiating planar beams scannable in a first angular coordinate and of substantially constant beam width in the same angular coordinate over a wide range of angles in a second orthogonal angular coordinate, comprising:

a dielectric lens in the shape of a partial toroid having circular-shaped inside and outside perimeter surfaces and a full circle cross-sectional shape in a plane containing the axis of said toroid;

a plurality of parallel-plate wave guide feeds coupled to said lens along a portion of said inside perimeter, said parallelplate wave guides being normal to the axis of said toroid and spaced in the direction of said axis, said parallel-plate wave guides further having their apertures abutting the inside surface of said toroid;

a scan feed array including a first linear array of antenna elements;

a plurality of second linear arrays of antenna elements, one within each of said parallel-plate wave guide feeds; and

a plurality of coupling transmission lines for coupling each element of said first linear array in parallel with corresponding elements in each of said second linear arrays.

2. Apparatus according to claim 1 in which said dielectric lens is defined as having an approximate dielectric constant of 4.

3. Apparatus according to claim 2 in which said scan feed array comprises the elements of a phased array.

4. Apparatus according to claim 2 in which said antenna elements of said first linear array comprise slots in an associated wave guide transmission line and each of said coupling transmission lines comprises a wave guide.

5. Apparatus according to claim 4 in which the number of said antenna elements in each of said second linear arrays equals the number of said elements in said first linear array, there also being an equal number of said coupling transmission lines.

6. Apparatus according to claim 5 in which each of said coupling transmission lines is coupled to said scan feed array through one of said slots of said first linear array and slots in said coupling transmission lines are provided coincidental with said corresponding antenna elements of each of said second arrays, whereby said parallel feed of corresponding elements of said second array is provided.