Method and device for providing a dummy target for protecting a vehicle and/or an object from radar-guided seeker heads

Abstract

A method and a device for providing a dummy target via decoy chaffs for protecting a vehicle and/or an object from radar-guided missiles. After identification of the radar-guided missile and calculation of a decoy chaff pattern, the decoy chaff pattern is presented in the form of polar coordinates in accordance with the firing of shots, a cut-off distance for the determination of a defence radius is then found in these polar coordinates. A minimum distance between the disassembly or detonation points within the defence radius is set. The dummy target is then optimized on the basis of the cut-off distance and the minimum distance between the disassembly or detonation points. As a result of this calculation, the only decoy chaffs that are deloyed are those that meet the conditions, i.e. that have a minimum distance between the disassembly or detonation points within the defence radius in the optimized dummy target.

Claims

1. A method for providing a dummy target via decoys for protecting a vehicle and/or object from radar-guided missiles, the method comprising: detecting an attack by a radar-guided missile; identifying the radar-guided missile; calculating a decoy pattern in accordance with a firing of shots; representing the decoy pattern as a point cloud of a disintegration or detonation point of the dummy target in a form of polar co-ordinates; ascertaining or defining a cut-off distance for determining a defense radius; defining a minimum distance between the disintegration or detonation points within the defense radius; optimizing the dummy target based on the cut-off distance and the minimum distance between the disintegration or detonation points; and deploying only the decoys that have the minimum distance between the disintegration or detonation points within the defense radius in the optimized dummy target.

2. The method as claimed in claim 1, wherein a cluster recognition of the point cloud having the disintegration or detonation points in the decoy pattern is carried out by a cluster algorithm.

3. The method as claimed in claim 1, wherein recognized clusters of the dummy target are thinned out from an outside inward.

4. The method as claimed in claim 1, wherein the dummy target is ascertained at substantially right angles to a threat or an approach angle of the radar-guided missile relative to the object.

5. The method as claimed in claim 1, wherein at least environmental influences such as course and speed of the object, wind direction, wind speed, speed and approach angle of the radar-guided missile are taken into account at an operation time.

6. A device for providing a dummy target via decoys for protecting a vehicle and/or object from radar-guided missiles, the device comprising: at least one sensor for identifying a missile after detecting an attack by the missile; at least one decoy launch system having at least one launcher, the decoy launch system being connected to the sensor directly or via a combat management system; and a database implemented in the decoy launch system, information about a multiplicity of known missiles being stored in the database, wherein the decoy launch system in reaction to a knowledge of the missile type, specifies a decoy pattern with disintegration or detonation points of the decoys present in the decoy launch system in a decoy pattern in accordance with a firing of shots after calculation, and wherein the disintegration or detonation points are represented in a polar co-ordinate system and, in a firing control system of the decoy launch system, a point cloud is optimized with an aid of a cluster analysis of the point cloud.

7. The device as claimed in claim 6, wherein the sensor is an electronic support measures (ESM) system.

8. The device as claimed in claim 6, wherein the decoy launch system is directable or non-directable in azimuth and/or elevation.

9. The device as claimed in claim 6, wherein the decoy launch system comprises one, two or a plurality of launchers.

10. The device as claimed in claim 9, wherein a plurality of launchers incorporated on the object are used.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

(2) FIG. 1 shows, in a block diagram illustration, an assembly of a protective device against radar-guided missiles;

(3) FIGS. 2a, b show an illustration of the decoys deployed in volleys;

(4) FIGS. 3a, b, 4a, b show an illustration of the optimization sequence for deploying the decoys;

(5) FIG. 5 shows a view from above given an approach direction of 60 from the north, and

(6) FIG. 6 shows a view from the viewpoint of the decoy in accordance with the illustration in FIG. 4a.

DETAILED DESCRIPTION

(7) FIG. 1 illustrates the essential assemblies of a protective device 100 for protecting an object 1 (FIG. 5), here a ship, against radar-guided missiles 2. The protective device 100 comprises at least one sensor 3 for recognizing or identifying the missile 2 and various sensors 4, 5, etc., which supply ambient data, etc. Components that detect a missile 2 attacking the object 1 are not illustrated in more specific detail, since such components or sensors are known.

(8) The sensor 3 is preferably an ESM system that can pick up the radar signal (frequency, signal waveform) of the seeker head 2.1 of the missile 2. With the aid of a database stored in the ESM system, the missile type of the missile 2 is ascertained in an evaluation. The sensor or sensors 4 supply the environmental data such as wind direction, wind speed, etc. The navigation data of the ship are contributed via the sensor 5. Incorporating and taking account of such information for providing a decoy cloud is known as such, reference being made explicitly to DE 103 46 001 B4, to which reference is hereby made.

(9) The protective device 100 furthermore comprises at least one decoy launch system (DLS) 7 which, for its part, has at least one launcher 8. However, the DLS 7 can also have two or a plurality of launchers 8, which are likewise directable or non-directable in azimuth and/or elevation. Preference is given to four launchers 8 (FIG. 6) each having eight magazines 12, said launchers being incorporated on the object 1. The DLS 7 comprises a firing control system (not illustrated in more specific detail), to which the ship's systems (e.g.: CMS, ESM, various sensors) and the control unit of the DLS 7 or of the launchers 8 are electronically connected. This connection is used to carry out the transmission of the control signals for directing the launcher(s) 8 (actuating signals in azimuth and/or elevation) of the DLS 7 and the signals for initiating the decoys 9 for forming a decoy cloud 10, said decoys being situated in the DLS 7 or in the launchers 8.

(10) A database 7.1 is implemented in the DLS 7, information about a multiplicity of known radar seeker heads being stored in said database. The DLS 7 is electronically linked to the ESM system 3 directly or via a CMS (combat management systems) 6. Said CMS 6 has the ability to take into consideration and evaluate all information of the sensors 3, 4, 5 and assemblies on the ship together in real time and to forward these evaluations. With omission of the CMS 6, this task is performed by the firing control system of the DLS 7. The DLS 7 is equipped with eight magazines 12 (12.1-12.4) in the present exemplary embodiment. However, this number of eight magazines 12 should not be regarded as limiting.

(11) The method proceeds as follows:

(12) Upon detection of the missile 2, the sensor 3 performs the identification of the missile 2. After identification, this information is transferred to the CMS 11, which also picks up the data of the sensors 4, 5. In co-ordination with the data of the sensors 4, 5, the DLS 7 offers a decoy pattern (point cloud) 20 (FIGS. 2a, 2b).

(13) In the firing control system of the DLS, the deployment of the decoys 9 is then optimized, which involves determining at the operation time the required length of a volley and how many decoys 9 are intended to be deployed or ignited per volley. The number of volleys and the number of decoys 9 per volley are freely definable by the user and emerge from the object to be protected.

(14) This calculation of the required decoys 9 for the optimized decoy cloud 10 is carried out both in an X-Y co-ordinate system (for the minimum distance condition) and in the form of polar co-ordinates (cut-off condition) in order to generate a point cloud 20 and thus to be able to perform the optimization more effectively. The optimized point cloud 20, for its part, then lies within a radar lobe (dashed line) defined depending on the missile 2.

(15) In the firing control system of the DLS 7, the point cloud is optimized with the aid of a cluster analysis of the point cloud 20. One known analysis here is the DBSCAN (source: Ester, Martin; Kriegel, Hans-Peter; Sander, Jrg; Xu, Xiaowei (1996). Simoudis, Evangelos; Han, Jiawei; Fayyad, Usama M., eds. A density-based algorithm for discovering clusters in large spatial databases with noise. Proceedings of the Second International Conference on Knowledge Discovery and Data Mining (KDD-96). AAAI Press. pp. 226-231). The point cloud 20 is optimized with the result of the cluster analysis.

(16) FIGS. 2a, 2b show the firing of the decoys 9 in a number of four volleys [1] to [4], wherein eight decoys 9 can be fired per volley. For the purpose of firing the four volleys [1] to [4], the at least one DLS 7 has eight magazines 12, in each of which four decoys 9 are introduced. That yields 32 dummy targets as overall dummy target for the present exemplary embodiment. FIGS. 2a, 2b here illustrate the viewpoint of a pattern (decoy pattern 20) from the approaching radar-guided missile 2 without optimization. Given a predefined minimum number of dummy targets (results from the value of the ship's signature to be complied with) for example of 20 dummy targets (for a frigate) which have to be deployed in order to guarantee protection of the object 1, the latitude for the optimization is then between 20 and 32 dummy targets.

(17) In order to optimize the dummy targets in accordance with FIG. 3a, a vertical distance between two successive volleys is freely defined by the user. The vertical distance is measured in the center of the volley. The center of the volley is determined by half the distance between the outer right-hand and outer left-hand magazines 12. The height of the center of the point cloud 20 (decoy pattern) is then freely defined (FIG. 3b). The height H is ascertained as the average value of the heights of the highest volley [1] and the lowest volley [4]. The height of a volley is defined as the horizontal midpoint of a volley, measured from the center of the volley. The center of the volley is determined by half the angle of the outermost right-hand 12.1 and the outermost left-hand 12.4 magazine 12.

(18) On the basis of these values, a polar co-ordinate radius (defense radius) P.sub.ris then subsequently defined, i.e. the cut-off distance, i.e. that distance from the midpoint of the point cloud 20 within which a threat from the ascertained missile 2 is to be expected. Disintegration or detonation points of the individual decoys 9 which lie outside this defined radius P.sub.r are not taken into account further in the calculation, rather they are discarded. The representation of this distance in polar co-ordinates (also circular co-ordinates) has a major advantage over a representation in Cartesian co-ordinates. Specifically the so-called radar lobe of a radar-guided missile 2 corresponds in cross section to the dashed line illustrated in FIG. 4a. If the disintegration or detonation points of the individual decoys 9 are situated within said radar lobe, a corresponding effect of the dummy target or of the decoy cloud 10 is guaranteed.

(19) The effect of the dummy target is furthermore impaired by the respective distance between the individual disintegration or detonation points. In order to generate an optimum effect of the dummy target or of the decoy cloud 10, the distances between the disintegration or detonation points must not fall below a specific value. The disintegration or detonation points are at a specific distance from one another in accordance with the firing of shots after calculation. Said distance can vary according to the flight angle of the radar-guided missile 2. In order to avoid an excessively small distance between the disintegration or detonation points, a distance that is freely defined for the user is taken into account as minimum distance between the points. In this case, the distance to be defined is to be measured from the viewpoint of the radar-guided missile 2. If this distance is undershot when the disintegration or detonation points are ascertained, these corresponding disintegration or detonation points are discarded by the calculation algorithm (FIG. 4b).

(20) The DBSCAN, a cluster algorithm, is used as a calculation algorithm for recognizing an undershooting of the minimum distance between the disintegration or detonation points. A cluster recognition is intended to be performed with the aid of the DBSCAN.

(21) The results of the DBSCAN are used to thin out clusters of the dummy target or of the decoy cloud 10 from the outside inward, in combination with the definition of the cut-off distance. In this case, the number of disintegration or detonation points discarded and decoys 9 dispensed with is as few as possible but as many as necessary. At the operation time, environmental influences such as course and speed of the object 1, and wind direction, wind speed, speed and approach angle of the radar-guided missile 2 are taken into account in the calculation. The resultant dummy target or the resultant and optimized decoy cloud 10 is always calculated as far as possible at right angles to the threat (approach angle of the radar-guided missile 2 relative to the object 1). The result of the calculation is forwarded to the PLC of the DLS 7, which then performs the firing of the individual decoys 9 and the directing of the DLS 7 or the launcher thereof in the axes (FIG. 5).

(22) The method for optimizing the decoy cloud 10 with respect to the missile 2 itself also takes effect given a plurality of launchers 8 of a DLS 7, which then produce in co-operation the desired dummy target or decoy cloud 10 (FIG. 5). To that end, all the launchers 8 of the DLS 7 report their achievable disintegration or detonation points for the corresponding volley. All the disintegration or detonation points are used for the cut-off and the minimum distance condition. This results in a reduction of the number of necessary and possible disintegration or detonation points.

(23) In addition, a check of the munition minimum condition for the total number of defined disintegration or detonation points (volley x number of decoys per volley) is also carried out here. If the number of disintegration or detonation points that remained is higher than the required number, the cut-off condition and the minimum distance condition (up to max. 18 m) are correspondingly reduced alternately until the required number of disintegration or detonation points (predefined number of dummy targets) is attained. If e.g. 40 disintegration or detonation points are attainable, but 32 are desired and 20 are required as a minimum, then an optimization of the decoy cloud or of the dummy target between 32 and 20 is carried out. This possibility of optimization also holds true for an individual launcher of the DLS 7.

(24) A dummy target cloud for the object 1 to be protected as illustrated in FIG. 6 arises as the result of the optimization.

(25) The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.