MULTISTATIC RADAR SYSTEM FOR AIRPORT MONITORING

• US 20120019407A1
• Filed: 03/04/2010
• Published: 01/26/2012
• Est. Priority Date: 03/09/2009
• Status: Active Grant

• Current Assignee: Office National D'Etudes et de Recherches Aerospatiales
• Original Assignee: Office National D'Etudes et de Recherches Aerospatiales
• Inventors: Lesturgie, Marc
• Granted Patent: US 8,654,002 B2
• Time in Patent Office: Days
• US Class Current: 342/36
• CPC Class Codes: G01S 13/003 Bistatic radar systems; Multistatic radar systems
• CPC Class Codes: G01S 2013/916 Airport surface monitoring [ASDE]

Abstract

The present disclosure relates to a method for monitoring targets on a runway, wherein emitting modules and receiving modules are alternately distributed along each one of longitudinal sides of the runway. Orthogonal signals are emitted in a narrowband by the emitting modules and coherently received in a coherent manner by the receiving modules. An object is detected on the runway on the basis of a distribution of the modules into meshes each including three pairs of neighbouring emitting modules and receiving modules and on the basis of a radio location of the object through triangulation and interferometry in at least one mesh. The modules are also used for analyzing a target moving on the runway, and for monitoring the trajectographies of an air target in the surroundings of the runway.

Claims

1. A method for monitoring targets on a runway by means of emitting modules and receiving module, wherein said emitting modules and said receiving modules are alternately distributed along each one of longitudinal sides of said runway and in that it includes emitting orthogonal signals by said emitting modules at a rate of at least two orthogonal signals per emitting module, receiving signals in said receiving modules coherently with emitting orthogonal signals by said emitting modules, and detecting an object on said runway based on a distribution of said modules into meshes each including three neighbor bistatic pairs of emitting module and receiving module and on a radio location of said object through triangulation and interferometry in at least one mesh.

2. A method according to claim 1, including emitting signals in part at a first linear polarization and in part at a second linear polarization orthogonal to said first polarization from each emitting module, and detecting an object includes periodically for each bistatic pair of emitting module and receiving module in a mesh, a polarimetric analysis of components according to said first and second polarizations of the signals received by said receiving module of said each bistatic pair and issued from the orthogonal signals at said first and second linear polarizations emitted by said emitting module of said each bistatic pair.

3. A method according to claim 1, wherein detecting an object includes periodically for each mesh, coherently subtracting a pre-stored free state of said runway from a current state of said runway derived from a processing of the signals received by said receiving modules of said each mesh.

4. A method according to claim 1, wherein detecting an object includes periodically for each mesh, determining a covariance matrix of an interferometric multistatic matrix of the signals received by said receiving modules in said each mesh and building a matched filter depending on said covariance matrix for filtering the received signals by said receiving modules in said each mesh.

5. A method according to claim 1, including analyzing a target moving on said runway, based on the distribution of said modules in the meshes, on a periodic analysis of the signals received by a front part of each receiving module through said runway, and on a periodic measurement of the variation of the efficient radar cross section of said target moving on said runway in the vicinity of bistatic axes of three pairs in a mesh substantially concurrent at the centre of said mesh.

6. A method according to claim 1, including monitoring a trajectography for an air target in the surroundings of the runway based on a periodic location of said air target through a multistatic interferometry of the signals received by said receiving modules in a three dimension space corresponding to the coordinates of the position of said air target by ignoring the Doppler effect, and through a combination of a processing of a multistatic matrix of said received signals and of the diversity of the Doppler effect.

7. A method according to claim 1, wherein the emitted orthogonal signals have different frequencies.

8. A system for monitoring targets on a runway by means of emitting modules and receiving modules, wherein said emitting modules and said receiving modules are alternately distributed along each one of the longitudinal sides of said runway, said emitting modules being able to emit orthogonal signals at a rate of at least two orthogonal signals per emitting module, and in that the system includes means for receiving signals in said receiving modules coherently with the emission of signals by said emitting modules, and means for detecting an object on said runway based on a distribution of said modules in meshes each including three neighbor pairs of emitting module and receiving module and on a radio location of said object through triangulation and interferometry in at least one mesh.

9. A system according to claim 8, including means for analyzing a target able to move on the runway based on the distribution of said modules in the meshes, on a periodic analysis of the signals able to be received by a front part of each receiving module through said runway, and on a periodic measurement of the variation of the efficient radar cross section of said target able to move on said runway in the vicinity of bistatic axes of three pairs in a mesh substantially concurrent at the centre of said mesh.

10. A system according to claim 8, including means for monitoring a trajectography of an air target in the surroundings of the runway based on a periodic location of said air target through a multistatic interferometry of the signals able to be received by said receiving modules in a three dimension space corresponding to the coordinates of the position of said air target by ignoring the Doppler effect, and through a combination of a processing of a multistatic matrix of said received signals and of the diversity of the Doppler effect.

11. A system according to claim 8, including centralized means for transmitting via optical fibers signals to be emitted by said emitting modules and for receiving via optical fibers signals to be received by said receiving modules.

12. A computer program adapted to be implemented in a system for monitoring targets on a runway by means of emitting modules and receiving modules, comprising instructions which, when the program is executed in the system, carry out receiving signals in said receiving modules coherently with emitting orthogonal signals emitted by said emitting modules, at a rate of at least two orthogonal signals per emitting module, said emitting modules and said receiving modules being alternately distributed along each one of the longitudinal sides of said runway, and detecting an object on said runway based on a distribution of said modules into meshes each including three neighbor pairs of emitting module and receiving module and on a radio location of said object through triangulation and interferometry in at least one mesh.