Agile-Beam Radar Notably for the Obstacle 'Sense and Avoid' Function

• US 20110221625A1
• Filed: 09/14/2010
• Published: 09/15/2011
• Est. Priority Date: 09/15/2009
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Cornic, Pascal, Le Bihan, Patrick, Kemkemian, Stéphane
• Granted Patent: US 8,432,307 B2
• Time in Patent Office: Days
• US Class Current: 342/29
• CPC Class Codes: G01S 13/424 Stacked beam radar
• CPC Class Codes: G01S 13/4463 using phased arrays
• CPC Class Codes: G01S 13/48 using multiple beams at emission or reception
• CPC Class Codes: G01S 13/933 of aircraft or spacecraft

Abstract

A radar device includes an antenna having at least two linear arrays of radiating elements being orthogonal to one another, a first array being used to focus a transmission beam in a first plane and a second beam being used to focus a reception beam in a second plane, orthogonal to the first plane. The focussing of the beam is obtained in the first plane by coloured emission followed by a reception beam formation by computation, and in that the focussing of the beam is obtained in the second plane using reception beam formation by computation. The coloured emission is carried out by combining antenna transmission sub-arrays in such a manner as to form a sum channel and a difference on reception channel according to the monopulse technique.

Claims

1. - A radar device comprising an antenna comprising at least two linear arrays of radiating elements being orthogonal to one another, a first array being used to focus a transmission beam in a first plane and a second beam being used to focus a reception beam in a second plane, orthogonal to the first plane, wherein the focussing of the beam being obtained in the first plane by coloured emission followed by a reception beam formation by computation, and the focussing of the beam being obtained in the second plane using reception beam formation by computation, the coloured emission being carried out by combining antenna transmission sub-arrays in such a manner as to form a sum channel and a difference on reception channel according to the monopulse technique.

2. - The radar device according to claim 1, wherein the first plane is the elevation plane and the second plane is the azimuthal plane.

3. - The radar device according to claim 1, wherein the first array being substantially vertical, a first sub-array is formed from the upper part of this array and a second sub-array is formed from its lower part.

4. - The radar device according to claim 1, wherein the coloured emission is carried out by means of a Barker code.

5. - The radar device according to claim 4, wherein a direct Barker code is emitted on the first sub-array and the same code inverted is emitted on the second sub-array.

6. - The radar device according to claim 1, wherein the coloured emission is carried out by means of a frequency code.

7. - The radar device according to claim 6, wherein the frequency coding consists in emitting the transmission signal at a given frequency on the first sub-array and in emitting the transmission signal at a different frequency, these two frequencies being orthogonal over the duration of the transmission pulse.

8. - The radar device according to claim 1, further comprising at least one additional array of radiating elements for focussing a transmission beam substantially parallel to the first array, the various transmission beams having different directions, each beam being dedicated to one part of the angular range to be covered.

9. - The radar device according to claim 1, wherein the second array comprises at least two lines of radiating elements forming an interferometer being ambiguous in elevation, the ambiguity being removed by focussing the beam in the direction targeted.

10. - The radar device according to claim 1, wherein the focussing is obtained in one plane by electronic scanning on transmission and in the other plane using beam formation by computation on reception.

11. - The radar device according to claim 1, wherein the transmission part and the reception part is constructed as a multilayer printed circuit, the radiating elements being etched onto one of the faces of the circuit, the active components being mounted onto the other face, the interconnection and distribution elements being formed on the internal layers of the printed circuit.

12. - The radar device according to claim 1, wherein it equips an aircraft for an obstacle detection and avoidance function.