摘要 |
An antenna excited by a symmetrical strip line (1) including two peripheral conductors (3, 3') positioned respectively above and below a central conductor (2). It comprises, at the end of the symetrical strip line, a first dipolar radiating element (10), including two quarter wave branches (11, 11') formed by extending each of the peripheral conductors (3, 3') in their plane and a quarter wave branch (12) formed by extending the central conductor (2) in its plane, in an opposite direction; a second dipolar radiating element (20), orthogonal to the first one, including two quarter wave branches (21, 22) formed by the folding of the cental conductor (2) and of one (3) of the peripheral conductors; and distributor and phase-shifter means (30) to excite the dipolar radiating elements (10, 20) by similar respective signals, having the same amplitude but being phase-shifted by 90 DEG . These distributor and phase-shifter means (30) are formed by an axial quarter wave segment of a symmetrical strip line (31, 32, 32' ), said symmetrical strip line segment extending the symmetrical strip supply line beyond the first dipolar radiating element, the branches of the second dipolar radiating element being formed at the end of this symmetrical strip line segment, and the dimensions of this symmetrical strip line segment and the inherent characteristics of its dielectric (33, 33') being chosen so as to excite the dipolar radiating elements by similar respective signals, having the same amplitude but being phase-shifted by 90 DEG .
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