Cruciform Antenna Comprising Linear Sub-Antennas and Associated Processing for Airborne Radar

• US 20080291096A1
• Filed: 05/12/2006
• Published: 11/27/2008
• Est. Priority Date: 05/16/2005
• Status: Abandoned Application

• Current Assignee: Jean-Marc Cortambert
• Original Assignee: Jean-Marc Cortambert
• Inventors: Cortambert, Jean-Marc
• Application Number:
  US11/914,665
• Publication Number:
  US 20080291096A1
• Time in Patent Office: Days
• US Class Current: 343/705
• CPC Class Codes: H01Q 1/28 Adaptation for use in or on aircraft, missiles, satellites, or balloons
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001

Abstract

The invention relates to an antenna (1) including:

• • a first (2) and a second (3) linear sub-antenna equipped with sensors (21-2M, 31-3N) forming first and second line portions and generating a basic signal (Si′, Gj′), wherein the angle between the directional vectors of the first and second tangents to the midpoint of the first and second line portions is between 30° and 150°;
  • a device for transmitting an electromagnetic signal at a frequency equal to at least 10 GHz;
  • an antenna processing device (4, 5) forming a plurality of combined signals (VSi, VGj);
  • a signal processing device (6, 7) generating combined signals (TSi, TGj);
  • a device (8) for calculating the correlation coefficients ([C_ij]) between the useful combined signals;
  • a device (8) generating a detection signal ([R_ij]) when a correlation coefficient exceeds a predetermined threshold.

Claims

1. Antenna (1) characterized in that it includes:

a first (2) and a second (3) linear sub-antenna;

each having a plurality of electromagnetic sensors (21-2M, 31-3N) arranged so as to form first and second line portions, respectively, with each sensor generating a basic signal (Si′

, Gj′

);

wherein the angle between the respective directional vectors of the first and second tangents to the midpoint respectively of the first and second line portions is between 30° and

150°

;

a device for transmitting an electromagnetic signal at a frequency equal to at least 10 GHz;

an antenna processing device (4, 5) forming a plurality of combined signals (VSi, VGj) for each line portion, which signal is a combination of basic signals of the sensors of this line portion;

a signal processing device (6, 7) generating combined signals (TSi, TGj) useful for filtering the noise of the combined signals coming from each line portion;

a device (8) for calculating the correlation coefficients ([Cij]) between the useful combined signals of the first line portion and the useful combined signals of the second line portion;

a device (8) generating a detection signal ([Rij]) when a correlation coefficient exceeds a predetermined threshold.

2. Antenna according to claim 1, characterized in that it also includes a target detection device, comparing each calculated correlation coefficient with a predefined associated threshold, detecting and locating a target when a correlation coefficient exceeds said threshold.

3. Antenna according to claim 2, characterized in that it includes a processing device (9) for processing the detection signal and the correlation coefficients generating information concerning the target detected.

4. Antenna according to claim 3, characterized in that the information generated includes the distance, the elevation angle, the bearing, the speed and an image of the target.

5. Antenna according to claim 3 or 4, characterized in that it includes a device (10) displaying the information generated.

6. Antenna according to claims 4 and 5, characterized in that the device (10) displays the image of the target only if another information item generated exceeds a predetermined threshold.

7. Antenna according to any one of the previous claims, characterized in that:

the sensors are transmissive;

the transmission device includes an excitation circuit supplying power to the sensors of the linear sub-antennas so that they transmit at a frequency equal to at least 10 GHz;

data processing device processes the combined signals according to the signal transmitted by each sensor, which processing includes, for example, a pulse compression.

8. Antenna according to any one of the previous claims, characterized in that the first and second line portions have a length between 30 and 150 cm and a width between 1 and 10 cm.

9. Aircraft including an antenna according to any one of the previous claims, characterized in that the first and second line portions are substantially straight and form substantially a V of which the base is oriented toward the top of the aircraft.

10. Aircraft according to claim 9, characterized in that the vectors directing the first and second line portions have an angle of between 40°

and 50°

with respect to the vertical of the aircraft.