| (19) |
 |
|
(11) |
EP 0 434 283 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
17.07.1991 Bulletin 1991/29 |
| (43) |
Date of publication A2: |
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26.06.1991 Bulletin 1991/26 |
| (22) |
Date of filing: 11.12.1990 |
|
| (51) |
International Patent Classification (IPC)5: H01Q 21/00 |
|
| (84) |
Designated Contracting States: |
|
DE ES FR GB IT |
| (30) |
Priority: |
22.12.1989 US 455036
|
| (71) |
Applicant: Hughes Aircraft Company |
|
Los Angeles, California 90045-0066 (US) |
|
| (72) |
Inventor: |
|
- Park, Pyong K.
Agoura Hills,
California 91301 (US)
|
| (74) |
Representative: Colgan, Stephen James et al |
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CARPMAELS & RANSFORD
43 Bloomsbury Square
London WC1A 2RA
London WC1A 2RA (GB) |
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| |
|
| (54) |
Planar array waveguide antenna with L-shaped series/series coupling slots |
(57) An array antenna which includes a first waveguide 12 coupled to a second waveguide
20 by an L-shaped coupling slot 30. The slot 30 has a first portion 32 orthogonal
to a second portion 34 thereof thereby providing the unique L-shape. In a specific
embodiment, the slot 30 is located with the first portion 32 along the centerline
and longitudinal axis of the first waveguide 12 and the second portion 34 along the
centerline and longitudinal axis of the second waveguide 20.
The folded short, as well as the tapered section of prior designs can be eliminated
by use of the L-shaped coupling slot of the present invention in the first and last
positions of the coupling slot because a short can be placed at the L-shaped slot.
Hence, the L-shaped coupling slot of the present invention provides a more compact
planar antenna than that afforded by conventional designs.