METHOD AND MONOPOLE ANTENNA FOR MAKING UNIFORM THE RADIATION OF SAID ANTENNA, WHEN DISPOSED INSIDE A RADOME

• US 20140240192A1
• Filed: 02/21/2014
• Published: 08/28/2014
• Est. Priority Date: 02/22/2013
• Status: Active Grant

• Current Assignee: Airbus Operations (European Aeronautic Defence and Space Company EADS NV), Office National D'Etudes et de Recherches Aerospatiales
• Original Assignee: Airbus Operations (European Aeronautic Defence and Space Company EADS NV), Office National D'Etudes et de Recherches Aerospatiales
• Inventors: JEULAND, Herv
• Granted Patent: US 9,281,555 B2
• Time in Patent Office: Days
• US Class Current: 343/872
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 1/421 Means for correcting aberrations introduced by a radome
• CPC Class Codes: H01Q 9/40 Element having extended radiating surface
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

Method and monopole antenna for making uniform the radiation of the antenna, when disposed inside a radome. According to the invention, on the surface of the monopole antenna is formed a protruding longitudinal ridge which is disposed at least approximately opposite an area of the radiating pattern of the assembly radome (1)-monopole antenna having a reduced gain in comparison with the radiating pattern of said monopole antenna alone.

Claims

1. A method for ensuring a uniform radiation pattern of an assembly comprising:

a monopole antenna, and

a radome with an aerodynamic profile, inside which said monopole antenna is positioned,

wherein the method comprises;

determining the radiation pattern of said antenna/radome assembly;

determining the directions, about the axis of said monopole antenna positioned inside said radome, in which said radiation pattern of the antenna/radome assembly has areas in which the gain values are reduced in comparison with the radiation pattern of said monopole antenna; and

modifying the surface of said monopole antenna, to form on it a protruding longitudinal ridge that is at least approximately facing at least one of said areas of reduced gain thus determined.

2. An assembly comprising:

a monopole antenna having a surface of revolution, and

a radome with an aerodynamic profile, inside which said monopole antenna is positioned,

wherein said monopole antenna comprises, on its surface of revolution, at least one protruding longitudinal ridge positioned at least approximately facing at least one of said areas of reduced gain.

3. The assembly according to claim 2, wherein:

said radome is a hollow body with an aerodynamic profile comprising two opposite side walls connected at their ends by a leading edge and by a trailing edge that define a median longitudinal plane for said radome,

the axis of said antenna is located at the intersection of the median longitudinal plane and the median transverse plane of said radome, and

the surface of said antenna comprises, transverse to said median longitudinal plane of said radome and on either side of said plane, two longitudinal ridges positioned respectively directly facing the corresponding side wall of said radome.

4. The assembly according to claim 3, wherein, on either side of each of said longitudinal ridges positioned directly facing the side walls of the radome, the surface of said monopole antenna comprises two longitudinal ridges obliquely facing the corresponding side wall of the radome.

5. The assembly according to claim 4, wherein said longitudinal ridges positioned directly facing the side walls of the radome and said longitudinal ridges positioned obliquely facing said side walls are portions of ellipses.

6. The assembly according to claim 5, wherein said longitudinal ridges belong to three ellipses centred on the axis of said antenna, the minor axes, major axes and relative orientations of which form parameters so as to optimise a uniform radiation pattern of said monopole antenna/radome assembly.

7. The assembly according to claim 4, wherein, on either side of the median longitudinal plane of the radome, the longitudinal ridge positioned directly facing the corresponding side wall of the radome and the two associated longitudinal ridges positioned obliquely facing the latter side wall merge to form a single, rounded lateral projection.

8. The assembly according to claim 7, wherein the surface of said antenna has a rounded groove, respectively facing said leading edge and said trailing edge of the radome.

9. The assembly according to claim 2, wherein the open end of said monopole antenna is closed by a plug.

10. The assembly according to claim 2, wherein said monopole antenna is positioned inside a hollow form of dielectric material taking on the shape of said antenna.

11. The assembly according to claim 2, wherein said radome is filled with foam of a permittivity close to 1, confining said monopole antenna and securing it to said radome.

12. A monopole antenna having a surface of revolution and intended to be positioned inside a radome with an aerodynamic profile, so as to form an antenna/radome assembly, the radiation pattern of said assembly having areas in which the gain values are reduced in comparison with the radiation pattern of said monopole antenna, characterised in that said monopole antenna comprises, on its surface of revolution, at least one protruding longitudinal ridge intended to face at least approximately at least one of said areas of reduced gain of said antenna is positioned inside said radome.