Abstract: The invention relates to an antenna comprising a plurality of metallic elements (10, 20, 30, 40), said metallic elements (10, 20, 30, 40) being in point contact (11, 21, 31, 41) with a ground plane (M) and equally distributed about a central axis of symmetry (D) of the antenna, perpendicular to the ground plane (M). The antenna of the invention is characterized in that each metallic element extends from the point contact at a non-zero angle of inclination (q) to said ground plane (M) and in that the ground plane (M) includes at least one cavity (80-83, 84-87) so that, in operation, the antenna matching is better in a specified frequency band than when the ground plane (M) has no cavities.

Abstract: The invention relates to an antenna of the helix type, comprising a plurality of radiating strands wound in a helix in an axisymmetric form (15), characterized in that each radiating strand is made up of at least one reference pattern (MR1, MR2, MR3) defined by an analytic function defined in a reference frame, the axis of the abscissae of which is the director axis of the radiating strands and is a periodic function of (I) or (II) and Ak correspond respectively to the frequency and to the amplitude of the sinusoid of index k.

Abstract: The invention relates to an antenna of the helix type, comprising a plurality of radiating strands wound in a helix in an axisymmetric form (15), characterized in that each radiating strand is made up of at least one reference pattern (MR1, MR2, MR3) defined by an analytic function defined in a reference frame, the axis of the abscissae of which is the director axis of the radiating strands and is a periodic function of (I) or (II) and Ak correspond respectively to the frequency and to the amplitude of the sinusoid of index k.

Abstract: The invention relates to a helix antenna comprising a plurality of radiating elements wound helically in an axisymmetric shape (15), characterized in that each radiating element comprises a repetition of the same pattern, which is defined by an at least second-order fractal (F1, F1? F2, F2?, F3, F3?, F4, F5).

Abstract: The invention relates to an antenna comprising a plurality of metallic elements (10, 20, 30, 40), said metallic elements (10, 20, 30, 40) being in point contact (11, 21, 31, 41) with a ground plane (M) and equally distributed about a central axis of symmetry (D) of the antenna, perpendicular to the ground plane (M). The antenna of the invention is characterized in that each metallic element extends from the point contact at a non-zero angle of inclination (q) to said ground plane (M) and in that the ground plane (M) includes at least one cavity (80-83, 84-87) so that, in operation, the antenna matching is better in a specified frequency band than when the ground plane (M) has no cavities.