EP0512202B1 - Method for protecting an IR-radiation emitting object and projectile for putting this method in practice - Google Patents

Method for protecting an IR-radiation emitting object and projectile for putting this method in practice Download PDF

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Publication number
EP0512202B1
EP0512202B1 EP92102852A EP92102852A EP0512202B1 EP 0512202 B1 EP0512202 B1 EP 0512202B1 EP 92102852 A EP92102852 A EP 92102852A EP 92102852 A EP92102852 A EP 92102852A EP 0512202 B1 EP0512202 B1 EP 0512202B1
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Prior art keywords
target
radiation
clouds
cloud
missile
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German (de)
French (fr)
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EP0512202A3 (en
EP0512202A2 (en
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Heinz Dipl.-Ing. Bannasch (Fh)
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Buck Chemisch Technische Werke GmbH and Co
Buck Werke GmbH and Co
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Buck Chemisch Technische Werke GmbH and Co
Buck Werke GmbH and Co
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F41WEAPONS
    • F41HARMOUR; ARMOURED TURRETS; ARMOURED OR ARMED VEHICLES; MEANS OF ATTACK OR DEFENCE, e.g. CAMOUFLAGE, IN GENERAL
    • F41H9/00Equipment for attack or defence by spreading flame, gas or smoke or leurres; Chemical warfare equipment
    • F41H9/06Apparatus for generating artificial fog or smoke screens

Definitions

  • the invention relates to a method for protecting objects emitting IR radiation according to the preamble of claim 1 and to a projectile for carrying out this method.
  • EP 0 240 819 A2 which describes a method of the generic type and in which throwing bodies producing dummy targets are placed and fired at predetermined times in predetermined spatial areas, in such a way that the dummy targets generated are at predetermined intervals in time and space on a Deflection curve and should be controlled by the missile so that its trajectory merges into the deflection curve and finally in the deflection direction.
  • the apparent target clouds consist of burning phosphor flares, that is, platelets or strips coated with red phosphorus, which are ejected from the throwing body at the desired location and ignited in the process.
  • an adaptive "tracking gate” is used in the imaging "gated video target search heads", which can be adapted exactly to the size of the ship to be hit by means of a video processor and suitable algorithms.
  • the viewing window of the seeker head can thus be reduced to the size of the ship after being switched on, with the result that apparent target clouds which are generated outside this adaptive window, that is to say above or next to the ship, remain ineffective.
  • the target is usually activated by a human operator.
  • the search head After switching to the object, the search head finds its way to the target unhindered by comparing (cross-correlation) two successive images (stored reference image / current image), even if IR apparent target clouds are generated in the vicinity of the object.
  • Another method for false target elimination consists in a frequency analysis by the seeker head, which can distinguish between the radiation characteristic of the IR emitter of the target having a comparatively low temperature (for example ship engines) and the radiation characteristic of a hot false target cloud.
  • the object of the present invention is therefore to provide a method and projectile with which it is possible to deflect missiles equipped with intelligent search heads from the target.
  • the invention is therefore based on the basic idea that a deflection of intelligent search heads is only possible if the reception of the ship's signature for the search head is considerably disturbed first, i.e. - seen from the search head - the ship's signature is permanently destroyed, i.e. the search head is a must make new goals. It is only at this point in time that it is possible to deflect using known IR target clouds that are attractive to the seeker head, that is, to have the seeker head connected to the dummy target clouds, provided, of course, that the actual target is "covered” in this way that the seeker head does not switch back to the actual target.
  • FIG. 1 shows the field of view A of an imaging IR seeker head.
  • this field of view A is the ship to be attacked.
  • the search field is reduced to a window B roughly corresponding to the size of the ship, with automatic adjustment regardless of the distance between the search head and ship. If, as is customary up to now, lateral fictitious target clouds are set from the ship, as shown in the figure, then these obviously remain ineffective because they are located outside the window B. If, however, the dummy target clouds were set up within window B, i.e. at a point between the ship and the approaching missile, the missile would not be deflected from the ship, i.e. the missile would maintain its - intended - trajectory.
  • the procedure according to the invention is such that large interference clouds, preferably successively "migrating" to the outside, are generated between the ship and the approaching missile, which initially disturb the reception of the ship's signature and thus cause the seeker head to be lost (FIG. 2) .
  • the seeker head switches to the outward focus of radiation; a renewed “recognition of the ship's signature” is prevented by the persistent camouflage effect of the interference radiation cloud.
  • the seeker head can now be gradually deflected from the ship. How this deflection process works in detail will be explained below.
  • the radiation course of the interference radiation cloud should be as shown in FIG. 3. More precisely, the radiance should rise very quickly to a high value in order to obtain the most possible delay-free effect, namely in that disturbances in the ship's signature are caused in the IR seeker head, which result in a loss of target. Likewise, the drop in the beam strength to a comparatively low value should take place very quickly in order to avoid a continued attraction of the seeker head.
  • the phase of strong radiation should last for a maximum of two to four seconds. This phase of high radiation intensity is then followed by a phase of comparatively low radiation intensity, for which a period of at least 15 seconds must be set. This phase of low beam intensity serves to ensure a permanent modification of the ship's signature. The modification is caused by temporally and spatially varying damping and radiation effects of the active substance.
  • the radiation intensity curve mentioned can be achieved by throwing bodies, the effective mass of which is a mixture of the following components: small-area phosphor flares: about 50% large phosphor flares: about 10% Phosphorus granules: about 40%
  • Optimization can be based on radiometer measurements for the relevant wavelength ranges.
  • FIG. 4 10 denotes the ship to be protected, 11 the missile flying towards the ship, which is equipped with an intelligent IR seeker head 11a. 12 indicates the flight path of the missile 11, and the dashed lines 13 correspond to the limitation of the viewing window of the seeker head 11a, which is already connected to the ship 10, that is to say the window B, for example of FIG. 1.
  • the approach of the missile 11 has been determined by the ship 10
  • its distance from the ship and its speed are determined.
  • three throwing bodies are now fired from the ship at short time intervals, for example at a distance of one second, which then generate interference radiation clouds at points 1, 2 and 3 of FIG. 4, i.e.
  • the throwing bodies release their active mass at about the height of the ship, i.e. at a height of 30 meters, by igniting the active mass.
  • the three interference radiation clouds 1, 2, 3 induce interference signals in the electronic seeker head components, such as the "target reference detector", the "gate generator” and / or the correlation computer, which lead to the destruction of the ship's signature, in the aforementioned first radiation phase in other words, a loss of the seeker target.
  • the first apparent target cloud 4 is deployed, specifically in the edge region of the viewing windows of the search head 11a delimited by the dashed lines 13.
  • the apparent target cloud 4 which is also produced in a conventional manner by a missile launched by the ship 10, should have a large area and a high radiation intensity in all relevant wavelength ranges.
  • the seeker head 11a will follow the radiation center of gravity of the apparent target clouds moving outwards, since these represent a much more attractive target than the ship 10 in terms of beam strength and area, especially since its IR signature is "blurred” or persistently “camouflaged” by the interference radiation clouds 1, 2, 3 can no longer be differentiated from the radiation from the background.
  • the approaching missile 11 is thus deflected ever further from the ship 10.
  • the apparent target clouds 4 to 9 are created using conventional active materials, which generally consist of phosphor flares.
  • the height of the flare decomposition should be at the top of window B, i.e. at ship height. If one assumes a height of 30 meters and a sinking speed of 2.5 m / s, the flare action time is 12 seconds.
  • Such a duration of action in conjunction with the above-mentioned generation sequence of 4 seconds of clouds 4 to 9, the large-scale dimension of the clouds and the preference for a radiation frequency adapted to the ship's radiation leads to an optimal deflection of the seeker head and thus of the missile.
  • the interference radiation clouds 1 to 3 and the apparent target clouds 4 to 9 lie essentially on a pitch circle around a center point, which is located on the ship 10.
  • Another great advantage of the creation of the apparent target clouds 4 to 9 on a pitch circle is that from the perspective of the missile, a coherent "apparent target band" is created, with the formation of a radiation center at the point furthest away from the ship.
  • dummy target clouds are 4 to 9 IR dummy targets, rather a combination of IR dummy target clouds, i.e. clouds made of phosphor flares, and RF clouds, i.e. clouds made of dowels, is advisable in order to appropriately interfere with search heads with radar control or to be able to distract.
  • the invention is not limited to the exemplary embodiment shown, rather numerous modifications are possible without leaving the scope of the invention.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)
  • Optical Radar Systems And Details Thereof (AREA)
  • Radar Systems Or Details Thereof (AREA)

Description

Die Erfindung betrifft ein Verfahren zum Schützen von eine IR-Strahlung abgebenden Objekten nach dem Oberbegriff des Patentanspruches 1 sowie einen Wurfkörper zur Durchführung dieses Verfahrens.The invention relates to a method for protecting objects emitting IR radiation according to the preamble of claim 1 and to a projectile for carrying out this method.

Es ist bekannt, eine IR-Strahlung abgebende Objekte, insbesondere Schiffe aber auch Flugzeuge und Panzer, dadurch gegen mit IR-Suchköpfen ausgerüstete Flugkörper zu schützen, daß bei Feststellung des Anflugs eines Flugkörpers mittels Wurfkörper im Luftraum benachbart dem Objekt eine oder - nacheinander - mehrere pyrotechnische Scheinzielwolken errichtet werden, die den IR-Suchkopf des Flugkörpers vom Objekt ab- und auf sich lenken. Beispielsweise wird auf die EP 0 240 819 A2 verwiesen, die ein Verfahren der gattungsgemäßen Art beschreibt und bei der jeweils zu vorgegebenen Zeitpunkten in vorgegebene Raumbereiche Scheinziele erzeugende Wurfkörper plaziert und gezündet werden, derart, daß die erzeugten Scheinziele in vorgegebenen zeitlichen und räumlichen Abständen auf einer Ablenkkurve liegen und vom Flugkörper nacheinander so angesteuert werden sollen, daß seine Flugbahn in die Ablenkkurve und schließlich in die Ablenkrichtung übergeht.It is known to protect an object emitting IR radiation, in particular ships, but also aircraft and tanks, against missiles equipped with IR seekers in that one or - in succession - several objects are detected adjacent to the object when a missile is approached by means of a missile in the airspace pyrotechnic dummy target clouds are erected, which deflect the IR seeker head of the missile from the object and towards it. For example, reference is made to EP 0 240 819 A2, which describes a method of the generic type and in which throwing bodies producing dummy targets are placed and fired at predetermined times in predetermined spatial areas, in such a way that the dummy targets generated are at predetermined intervals in time and space on a Deflection curve and should be controlled by the missile so that its trajectory merges into the deflection curve and finally in the deflection direction.

Die Scheinzielwolken bestehen dabei aus brennenden Phosphorflares, also mit rotem Phosphor beschichteten Plättchen oder Streifen, die an der gewünschten Stelle in vorgegebener Höhe aus dem Wurfkörper ausgestoßen und dabei angezündet werden.The apparent target clouds consist of burning phosphor flares, that is, platelets or strips coated with red phosphorus, which are ejected from the throwing body at the desired location and ignited in the process.

Die neueste Entwicklung bei IR-Suchköpfen geht nun aber dahin, die Suchköpfe "intelligent" und somit gegen herkömmliche IR-Scheinziele immun zu machen, d.h. so auszubilden, daß sie auf die Objektsignatur, insbesondere Schiffssignatur, ansprechen. Dabei wird die Entwicklung in verschiedenen Richtungen vorangetrieben. So wird beispielsweise bei den abbildenden "gated video - Zielsuchköpfen" ein adaptives "tracking gate" eingesetzt, das mittels Videoprozessor und geeigneter Algorithmen exakt an die Größe des zu treffenden Schiffes angepaßt werden kann. Das Sichtfenster des Suchkopfs kann damit nach dem Aufschalten auf die Schiffsgröße verkleinert werden, mit der Folge, daß Scheinzielwolken, die außerhalb dieses adaptiven Fensters erzeugt werden, also über oder neben dem Schiff, wirkungslos bleiben. Bei den "correlation trackers" erfolgt die Zielaufschaltung meist durch einen menschlichen Operator. Nach dem Aufschalten auf das Objekt findet der Suchkopf dann durch Vergleich (Kreuzkorrelation) zweier nacheinanderfolgender Bilder (gespeichertes Referenzbild/aktuelles Bild) seinen Weg ungehindert ins Ziel, auch wenn in der Nähe des Objekts IR-Scheinzielwolken erzeugt werden. Eine weitere Methode zur Falschzielausscheidung besteht in einer Frequenzanalyse durch den Suchkopf, der zwischen der Strahlungscharakteristik der eine vergleichsweise niedrige Temperatur aufweisenden IR-Strahler (beispielsweise Schiffsmotoren) des Ziels und der Strahlungscharakteristik einer heißen Scheinzielwolke unterscheiden kann. Zusammengefaßt ist somit zu sagen, daß die bekannten IR-Scheinzielwolken nicht in der Lage sind, ein Objekt gegen mit intelligenten Suchköpfen ausgerüstete Flugkörper zu schützen, Aufgabe der vorliegenden Erfindung ist es deshalb, ein Verfahren und Wurfkörper zu schaffen, mit deren Hilfe es gelingt, auch mit intelligenten Suchköpfen ausgestattete Flugkörper vom Ziel abzulenken.However, the latest development in IR seekers is now to make the seekers "intelligent" and thus immune to conventional IR dummy targets, ie to design them in such a way that they respond to the object signature, in particular the ship's signature. The development is being driven in different directions. For example, an adaptive "tracking gate" is used in the imaging "gated video target search heads", which can be adapted exactly to the size of the ship to be hit by means of a video processor and suitable algorithms. The viewing window of the seeker head can thus be reduced to the size of the ship after being switched on, with the result that apparent target clouds which are generated outside this adaptive window, that is to say above or next to the ship, remain ineffective. With "correlation trackers", the target is usually activated by a human operator. After switching to the object, the search head finds its way to the target unhindered by comparing (cross-correlation) two successive images (stored reference image / current image), even if IR apparent target clouds are generated in the vicinity of the object. Another method for false target elimination consists in a frequency analysis by the seeker head, which can distinguish between the radiation characteristic of the IR emitter of the target having a comparatively low temperature (for example ship engines) and the radiation characteristic of a hot false target cloud. To summarize, it can be said that the known IR-shining target clouds are not able to To protect an object against missiles equipped with intelligent search heads, the object of the present invention is therefore to provide a method and projectile with which it is possible to deflect missiles equipped with intelligent search heads from the target.

Erfindungsgemäß wird diese Aufgabe verfahrensmäßig durch die Merkmale des Patentanspruches 1 und vorrichtungsmäßig durch die Merkmale des Patentanspruches 9 gelöst.According to the invention, this object is achieved procedurally by the features of patent claim 1 and device-wise by the features of patent claim 9.

Besondere Ausführungsformen des Verfahrens und der Vorrichtung bzw. des Wurfkörpers nach der Erfindung sind Gegenstand der entsprechenden Unteransprüche.Particular embodiments of the method and the device or the throwing body according to the invention are the subject of the corresponding subclaims.

Die Erfindung geht also von dem Grundgedanken aus, daß eine Ablenkung intelligenter Suchköpfe nur dann möglich ist, wenn zuerst der Empfang der Schiffssignatur für den Suchkopf beträchtlich gestört wird, also - vom Suchkopf her gesehen - eine anhaltende Zerstörung der Schiffsignatur erfolgt, der Suchkopf also eine neue Zielbestimmung vornehmen muß. Erst zu diesem Zeitpunkt ist es dann möglich, mittels bekannter, für den Suchkopf attraktiver IR-Scheinzielwolken eine Ablenkung vorzunehmen, also den Suchkopf auf die Scheinzielwolken aufschalten zu lassen, freilich unter der Voraussetzung, daß zu diesem Zeitpunkt das eigentlich Ziel derart "abgedeckt" ist, daß der Suchkopf nicht wieder auf das eigentliche Ziel aufschaltet.The invention is therefore based on the basic idea that a deflection of intelligent search heads is only possible if the reception of the ship's signature for the search head is considerably disturbed first, i.e. - seen from the search head - the ship's signature is permanently destroyed, i.e. the search head is a must make new goals. It is only at this point in time that it is possible to deflect using known IR target clouds that are attractive to the seeker head, that is, to have the seeker head connected to the dummy target clouds, provided, of course, that the actual target is "covered" in this way that the seeker head does not switch back to the actual target.

Die Erfindung wird nachfolgend anhand der Zeichnung näher erläutert. Auf der Zeichnung zeigen:

Fig. 1
eine grafische Darstellung zur Erläuterung der Unwirksamkeit üblicher IR-Scheinzielwolken gegenüber einen Suchkopf mit adaptivem "tracking gate",
Fig. 2
eine grafische Darstellung ähnlich derjenigen von Fig. 1, zur Erläuterung der Wirksamkeit des Erfindungsverfahrens auch bei einem Suchkopf mit adaptivem"tracking gate",
Fig. 3
eine Grafik des Strahlstärkeverlaufs bei einer Störstrahlungswolke nach der Erfindung, und
Fig. 4
eine Schemaskizze der Ablenkung eines anfliegenden Flugkörpers mit intelligentem Suchkopf.
The invention is explained below with reference to the drawing. Show on the drawing:
Fig. 1
2 shows a graphical representation to explain the ineffectiveness of conventional IR dummy target clouds compared to a seeker head with adaptive "tracking gate",
Fig. 2
2 shows a graphic representation similar to that of FIG. 1, to explain the effectiveness of the inventive method even with a seeker head with adaptive "tracking gate",
Fig. 3
a graph of the radiant intensity curve for an interference radiation cloud according to the invention, and
Fig. 4
a schematic sketch of the deflection of an approaching missile with an intelligent seeker head.

In Fig. 1 ist das Sehfeld A eines abbildenden IR-Suchkopfs dargestellt. In diesem Sehfeld A befindet sich das anzugreifende Schiff. Nach dem Aufschalten des Suchkopfs auf das Ziel (Schiff) verkleinert sich das Suchfeld auf ein der Größe des Schiffs in etwa entsprechendes Fenster B, und zwar mit automatischer Anpassung unabhängig von der Entfernung zwischen Suchkopf und Schiff. Werden nun vom Schiff aus, wie bisher üblich, seitliche Scheinzielwolken gesetzt, wie dies in der Figur dargestellt ist, dann bleiben diese offensichtlich wirkungslos, weil sie sich außerhalb des Fensters B befinden. Würde man aber die Scheinzielwolken innerhalb des Fensters B errichten, also an einer Stelle zwischen Schiff und anfliegendem Flugkörper, würde es zu keiner Ablenkung des Flugkörpers vom Schiff kommen, das heißt der Flugkörper würde seine - beabsichtigte - Flugbahn einhalten.1 shows the field of view A of an imaging IR seeker head. In this field of view A is the ship to be attacked. After the search head is switched to the target (ship), the search field is reduced to a window B roughly corresponding to the size of the ship, with automatic adjustment regardless of the distance between the search head and ship. If, as is customary up to now, lateral fictitious target clouds are set from the ship, as shown in the figure, then these obviously remain ineffective because they are located outside the window B. If, however, the dummy target clouds were set up within window B, i.e. at a point between the ship and the approaching missile, the missile would not be deflected from the ship, i.e. the missile would maintain its - intended - trajectory.

Im Gegensatz dazu wird nun gemäß der Erfindung so verfahren, daß zwischen Schiff und anfliegendem Flugkörper großflächige, vorzugsweise nacheinander nach außen "wandernde" Störstrahlungswolken erzeugt werden, die zunächst einmal den Empfang der Schiffssignatur stören und so einen Zielverlust des Suchkopfs herbeiführen (Fig. 2). Der Suchkopf schaltet auf den nach außen wandernden Strahlungsschwerpunkt auf; ein erneutes "Erkennen der Schiffssignatur" wird durch die anhaltende Tarnwirkung der Störstrahlungswolke verhindert. Durch den Einsatz herkömmlicher IR-Scheinzielwolken D kann nun der Suchkopf schrittweise vom Schiff abgelenkt werden. Wie dieser Ablenkvorgang im einzelnen abläuft, wird nachfolgend noch erläutert werden.In contrast to this, the procedure according to the invention is such that large interference clouds, preferably successively "migrating" to the outside, are generated between the ship and the approaching missile, which initially disturb the reception of the ship's signature and thus cause the seeker head to be lost (FIG. 2) . The seeker head switches to the outward focus of radiation; a renewed "recognition of the ship's signature" is prevented by the persistent camouflage effect of the interference radiation cloud. By using conventional IR dummy target clouds D, the seeker head can now be gradually deflected from the ship. How this deflection process works in detail will be explained below.

Der Strahlungsverlauf der Störstrahlungswolke soll so sein, wie in Fig. 3 dargestellt ist. Genauer gesagt, die Strahlstärke soll sehr schnell auf einen hohen Wert ansteigen, um so eine möglichst verzögerungsfreie Wirkung zu erhalten, nämlich dahingehend, daß im IR-Suchkopf Störungen der Schiffssignatur hervorgerufen werden, die einen Zielverlust zur Folge haben. Ebenso soll der Abfall der Strahlstärke auf einen vergleichsweise niedrigen Wert sehr schnell erfolgen, um eine anhaltende Attraktion des Suchkopfs zu vermeiden. Die Phase starker Strahlung soll eine Dauer von maximal zwei bis vier Sekunden haben. An diese Phase hoher Strahlungsstärke schließt sich dann eine Phase vergleichsweise niedriger Strahlungsstärke an, für die eine Zeitdauer von zumindest 15 Sekunden anzusetzen ist. Diese Phase geringer Strahlstärke dient dazu, für eine anhaltende Modifikation der Schiffssignatur zu sorgen. Die Modifikation wird durch zeitlich und räumlich variierende Dämpfungs- und Überstrahlungseffekte der Wirksubstanz hervorgerufen.The radiation course of the interference radiation cloud should be as shown in FIG. 3. More precisely, the radiance should rise very quickly to a high value in order to obtain the most possible delay-free effect, namely in that disturbances in the ship's signature are caused in the IR seeker head, which result in a loss of target. Likewise, the drop in the beam strength to a comparatively low value should take place very quickly in order to avoid a continued attraction of the seeker head. The phase of strong radiation should last for a maximum of two to four seconds. This phase of high radiation intensity is then followed by a phase of comparatively low radiation intensity, for which a period of at least 15 seconds must be set. This phase of low beam intensity serves to ensure a permanent modification of the ship's signature. The modification is caused by temporally and spatially varying damping and radiation effects of the active substance.

Der erwähnte Strahlungsstärkenverlauf kann durch Wurfkörper erreicht werden, deren Wirkmasse ein Gemisch aus folgenden Bestandteilen ist: kleinflächige Phosphorflares: etwa 50% großflächige Phosphorflares: etwa 10% Phosphorgranulat: etwa 40% The radiation intensity curve mentioned can be achieved by throwing bodies, the effective mass of which is a mixture of the following components: small-area phosphor flares: about 50% large phosphor flares: about 10% Phosphorus granules: about 40%

Eine Optimierung kann anhand von Radiometermessungen für die relevanten Wellenlängenbereiche erfolgen.Optimization can be based on radiometer measurements for the relevant wavelength ranges.

Der Vorgang der Ablenkung eines anfliegenden Flugkörpers wird nun anhand von Fig. 4 erläutert. In Fig. 4 ist mit 10 das zu schützende Schiff, mit 11 der auf das Schiff zufliegende Flugkörper, der mit einem intelligenten IR-Suchkopf 11a ausgerüstet ist, bezeichnet. 12 deutet die Flugbahn des Flugkörpers 11 an, und die gestrichelten Linien 13 entsprechen der Begrenzung des Blickfensters des bereits auf das Schiff 10 aufgeschaltenten Suchkopfs 11a, also etwa das Fenster B von Fig. 1. Sobald nun vom Schiff 10 aus der Anflug des Flugkörpers 11 festgestellt worden ist, werden dessen Abstand zum Schiff und dessen Geschwindigkeit ermittelt. In Abhängigkeit von diesen Werten werden nun vom Schiff aus in kurzen zeitlichen Abständen, beispielsweise mit einem Abstand von einer Sekunde, drei Wurfkörper abgeschossen, die dann an den Stellen 1, 2 und 3 von Fig. 4 Störstrahlungswolken erzeugen, also an Stellen, die zwischen Schiff 10 und Flugkörper 11 nebeneinanderliegen und im wesentlichen den Bereich zwischen den Begrenzungen 13 abdecken. Die Wurfkörper geben ihre Wirkmasse etwa in Schiffshöhe, also etwa in einer Höhe von 30 Metern, frei, und zwar unter Anzünden der Wirkmasse. Durch die drei Störstrahlungswolken 1, 2, 3 werden in der erwähnten ersten Strahlungsphase Störsignale in den elektronischen Suchkopfkomponenten, etwa dem "target reference detector", dem "gate generator" und/oder dem Korrelationscomputer induziert, die zu einer Vernichtung der Schiffssignatur führen, mit anderen Worten, zu einem Zielverlust des Suchkopfs.The process of deflecting an approaching missile will now be explained with reference to FIG. 4. In FIG. 4, 10 denotes the ship to be protected, 11 the missile flying towards the ship, which is equipped with an intelligent IR seeker head 11a. 12 indicates the flight path of the missile 11, and the dashed lines 13 correspond to the limitation of the viewing window of the seeker head 11a, which is already connected to the ship 10, that is to say the window B, for example of FIG. 1. As soon as the approach of the missile 11 has been determined by the ship 10, its distance from the ship and its speed are determined. Depending on these values, three throwing bodies are now fired from the ship at short time intervals, for example at a distance of one second, which then generate interference radiation clouds at points 1, 2 and 3 of FIG. 4, i.e. at points between Ship 10 and missile 11 lie next to each other and essentially cover the area between the boundaries 13. The throwing bodies release their active mass at about the height of the ship, i.e. at a height of 30 meters, by igniting the active mass. The three interference radiation clouds 1, 2, 3 induce interference signals in the electronic seeker head components, such as the "target reference detector", the "gate generator" and / or the correlation computer, which lead to the destruction of the ship's signature, in the aforementioned first radiation phase in other words, a loss of the seeker target.

Unmittelbar nach Erstellung der letzten Störstrahlungswolke wird die erste Scheinzielwolke 4 ausgebracht, und zwar im Randbereich der von den gestrichelten Linien 13 begrenzten Sichtfenster des Suchkopfs 11a. Die in herkömmlicher Art ebenfalls von einem vom Schiff 10 abgeschossenen Wurfkörper erzeugte Scheinzielwolke 4 soll großflächig sein und eine hohe Strahlstärke in allen relevanten Wellenlängenbereichen aufweisen.Immediately after the last interference radiation cloud has been created, the first apparent target cloud 4 is deployed, specifically in the edge region of the viewing windows of the search head 11a delimited by the dashed lines 13. The apparent target cloud 4, which is also produced in a conventional manner by a missile launched by the ship 10, should have a large area and a high radiation intensity in all relevant wavelength ranges.

Durch weitere Scheinzielwolken 5, 6, 7, 8 und 9, erstellt jeweils in Zeitabständen von beispielweise 4 Sekunden, wird in der Projektion des Suchkopfes ein strahlender, horizontaler, schiffsähnlicher "Schlauch" gebildet, dessen Strahlungsschwerpunkt kontinuierlich nach außen (von 4 nach 9) wandert.Additional shining target clouds 5, 6, 7, 8 and 9, each created at intervals of 4 seconds, for example, form a radiating, horizontal, ship-like "tube" in the projection of the seeker head, the center of radiation of which is continuously outward (from 4 to 9) wanders.

Der Suchkopf 11a wird dem nach außen wandernden Strahlungsschwerpunkt der Scheinzielwolken folgen, da diese bezüglich Strahlstärke und Fläche ein wesentlich attraktiveres Ziel darstellen als das Schiff 10, zumal dessen IR-Signatur durch die Tarnwirkung der Störstrahlungswolken 1, 2, 3 anhaltend "verwischt" wird bzw. nicht mehr gegenüber der Strahlung des Hintergrundes unterschieden werden kann.The seeker head 11a will follow the radiation center of gravity of the apparent target clouds moving outwards, since these represent a much more attractive target than the ship 10 in terms of beam strength and area, especially since its IR signature is "blurred" or persistently "camouflaged" by the interference radiation clouds 1, 2, 3 can no longer be differentiated from the radiation from the background.

Der anfliegende Flugkörper 11 wird somit immer weiter vom Schiff 10 abgelenkt.The approaching missile 11 is thus deflected ever further from the ship 10.

Die Scheinzielwolken 4 bis 9 werden, wie schon erwähnt, mittels herkömmlicher Wirkmassen erstellt, die im allgemeinen aus Phosphorflares bestehen. Die Höhe der Flarezerlegung soll am oberen Rand des Fensters B, also in Schiffshöhe, erfolgen. Legt man eine Höhe von 30 Meter und eine Sinkgeschwindigkeit von 2,5 m/s zugrunde, so ergibt sich eine Flarewirkungsdauer von 12 Sekunden. Eine solche Wirkungsdauer in Verbindung mit der oben angegebenen Erzeugungsfolge von 4 Sekunden der Wolken 4 bis 9, der großflächigen Dimension der Wolken und der Bevorzugung einer der Schiffsstrahlung angepaßten Strahlungsfrequenz, führt zu einer optimalen Ablenkung des Suchkopfs und damit des Flugkörpers.As already mentioned, the apparent target clouds 4 to 9 are created using conventional active materials, which generally consist of phosphor flares. The height of the flare decomposition should be at the top of window B, i.e. at ship height. If one assumes a height of 30 meters and a sinking speed of 2.5 m / s, the flare action time is 12 seconds. Such a duration of action in conjunction with the above-mentioned generation sequence of 4 seconds of clouds 4 to 9, the large-scale dimension of the clouds and the preference for a radiation frequency adapted to the ship's radiation leads to an optimal deflection of the seeker head and thus of the missile.

Wie aus Fig. 4 ersichtlich ist, liegen die Störstrahlungswolken 1 bis 3 und die Scheinzielwolken 4 bis 9 im wesentlichen auf einem Teilkreis um einen Mittelpunkt, der sich auf dem Schiff 10 befindet. Dies hat den Vorteil, daß alle die Wolken 1 bis 9 erzeugenden Wurfkörper von einer einzigen Abschußplattform nacheinander abgefeuert werden können, wobei es lediglich erforderlich ist, die Plattform schrittweise zu verschwenken. Dabei ist meist eine Höhenverstellung der Plattform während dieser Schwenkbewegung nicht erforderlich, es sei denn, das Schiff 10 führt während des Vorgangs der Abschüsse starke Bewegungen (Seegang) durch. Ein weiterer großer Vorteil der erläuterten Erstellung der Scheinzielwolken 4 bis 9 auf einem Teilkreis besteht darin, daß aus der Perspektive des Flugkörpers ein zusammenhängendes "Scheinzielband" entsteht, und zwar mit Bildung eines Strahlungsschwerpunkts am vom Schiff vom weitesten entfernten Punkt.As can be seen from FIG. 4, the interference radiation clouds 1 to 3 and the apparent target clouds 4 to 9 lie essentially on a pitch circle around a center point, which is located on the ship 10. This has the advantage that all of the throwing bodies producing clouds 1 to 9 can be fired in succession from a single launching platform, it being only necessary to gradually pivot the platform. It is usually not necessary to adjust the height of the platform during this pivoting movement, unless the ship 10 is guiding during the process the shots are caused by strong movements (swell). Another great advantage of the creation of the apparent target clouds 4 to 9 on a pitch circle is that from the perspective of the missile, a coherent "apparent target band" is created, with the formation of a radiation center at the point furthest away from the ship.

Mit Hilfe des zirkularen Ausbringungsverfahrens ist ferner ein schneller, jeweils optimal auf die Bedrohungsrichtung abgestimmter Einsatz der Wurfkörper gewährleistet, und zwar mit einer Ablenkrichtung stets rechtwinkelig zur Bedrohungsrichtung.With the help of the circular application process, a faster deployment of the throwing bodies, each optimally adapted to the threat direction, is guaranteed, with a deflection direction always perpendicular to the threat direction.

Es ist nicht erforderlich, daß alle Scheinzielwolken 4 bis 9 IR-Scheinziele sind, vielmehr ist eine Kombination aus IR-Scheinzielwolken, also Wolken aus Phosphorflares, und RF-Wolken, also Wolken aus Düppeln zweckmäßig, um auch Suchköpfe mit Radarsteuerung entsprechend stören bzw. ablenken zu können.It is not necessary that all of the dummy target clouds are 4 to 9 IR dummy targets, rather a combination of IR dummy target clouds, i.e. clouds made of phosphor flares, and RF clouds, i.e. clouds made of dowels, is advisable in order to appropriately interfere with search heads with radar control or to be able to distract.

Selbstverständlich ist die Erfindung nicht auf das dargestellte Ausführungsbeispiel beschränkt, vielmehr sind zahlreiche Abwandlungen möglich, ohne den Bereich der Erfindung zu verlassen. Dies betrifft die Zahl der zu erstellenden Störstrahlungs- und Scheinzielwolken, deren zeitliche und räumliche Abstände, die Zusammensetzung ihrer Wirkmassen, das Kaliber der Wurfkörper und die Zahl und Bewegung der Abschußrohre (Werfer). Darüberhinaus sind viele Möglichkeiten der Steuerung der Werfer auf der Basis vorprogrammierter oder bedrohungsabhängiger Computeranlagen gegeben. Auf jeden Fall aber muß gewährleistet sein, daß zunächst die Schiffssignatur zerstört wird, weil es erst dann möglich ist, einen Ablenkvorgang einzuleiten.Of course, the invention is not limited to the exemplary embodiment shown, rather numerous modifications are possible without leaving the scope of the invention. This applies to the number of interference and false target clouds to be created, their temporal and spatial distances, the composition of their active masses, the caliber of the projectiles and the number and movement of the launch tubes (thrower). In addition, there are many options for controlling the thrower on the basis of pre-programmed or threat-dependent computer systems. In any case, it must be ensured that the ship's signature is destroyed first, because it is only then possible to initiate a deflection process.

Claims (10)

  1. A method of protecting IR-radiating targets (10), more particularly ships, from missiles (11) having smart, more particularly scanning, imaging correlating and/or spectrally filtering IR search heads (11a), the missile (11) being located from the target (10) to be protected and the missile speed, flight direction and instantaneous distance from the target (10) being determined, characterised in that at least one large-area and homogeneous pyrotechnical interference radiation cloud (1, 2, 3) is produced from the target (10) for protection closely adjacent the same and between it and the missile (11), such cloud first emits a brief and intensive IR radiation which inhibits reception of the characteristic IR signature of the target (10) by the search head (11a) and disturbs its latch-on and pursuit electronics, and then for a comparatively long time emits a weak transmission-reducing IR radiation substantially in simulation of background radiation, and in that starting immediately after termination of the intense radiation phase of the interference radiation cloud (1 - 3) but at least during the weak radiation phase thereof a number of large-area and homogeneous pyrotechnical infrared dummy target clouds (4 - 9) substantially resembling the IR signature of the target (10) are fired therefrom consecutively, the dummy target clouds (4 - 9) being so cohesively adjacent one another starting from a place adjacent the interference radiation cloud (1 - 3) as to guide the search (11a) and therefore the missile (11) stepwise away from the target (10) in a substantially transverse direction to the missile approach direction.
  2. A method according to claim 1, characterised in that a number of large-area interference radiation clouds (1 - 3) are produced adjacent one another at short intervals of time between the target (10) for protection and the missile (11).
  3. A method according to claim 2, characterised in that the time intervals are of the order of magnitude of one second.
  4. A method according to any of claims 1 to 3, characterised in that the dummy target clouds (4 - 9) are produced at intervals of two to ten seconds, preferably four seconds.
  5. A method according to any of claims 1 to 4, characterised in that the intense IR radiation phase of the interference radiation cloud (1, 2, 3) lasts approximately two seconds and the subsequent weak radiation and transmission reduction phase lasts at least 10 seconds.
  6. A method according to any of claims 1 to 5, characterised in that radar dummy target clouds are produced in addition to the IR location dummy target clouds (4 - 9).
  7. A method according to any of claims 1 to 6, characterised in that at least the dummy target clouds (4 - 9) are produced on a partial circle whose centre is on the target (10) for protection.
  8. A method according to claim 7, characterised in the dummy target cloud partial circle is substantially a quadrant.
  9. A projectile for producing the interference radiation cloud (1 - 3) in the method according to any of the previous claims, characterised in that the active composition of the projectile is a mixture of approximately 10% of large-area phosphorus flares, approximately 50% of small-area phosphorus flares and the mixture of approximately 40% phosphorus granulate, the intense IR radiation phase of the interference radiation cloud (1, 2, 3) produced by the projectile lasting about two seconds.
  10. A projectile for the practice of the method according to any of claims 1 to 8 or claim 9, characterised by identical calibre for the production of interference radiation clouds (1 - 3) and for the production of dummy target clouds (4 - 9).
EP92102852A 1991-05-10 1992-02-20 Method for protecting an IR-radiation emitting object and projectile for putting this method in practice Expired - Lifetime EP0512202B1 (en)

Applications Claiming Priority (2)

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DE4115384A DE4115384C2 (en) 1991-05-10 1991-05-10 Method for protecting objects emitting IR radiation
DE4115384 1991-05-10

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EP0512202A2 EP0512202A2 (en) 1992-11-11
EP0512202A3 EP0512202A3 (en) 1993-09-01
EP0512202B1 true EP0512202B1 (en) 1996-04-10

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DE102005020159B4 (en) 2005-04-29 2007-10-04 Rheinmetall Waffe Munition Gmbh Camouflage and deception ammunition for the protection of objects against missiles
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DE102007032112A1 (en) 2007-07-09 2009-01-15 Rheinmetall Waffe Munition Gmbh Method and launcher for protecting an object from a threat, in particular a missile, and ammunition
WO2012028257A1 (en) * 2010-08-31 2012-03-08 Rheinmetall Waffe Munition Gmbh Device and method for producing an effective fog wall or fog cloud
DE102011014599B4 (en) * 2011-03-22 2016-12-08 Diehl Bgt Defence Gmbh & Co. Kg A method of protecting an object from attack by an approaching flying object
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US5291818A (en) 1994-03-08
DE59205935D1 (en) 1996-05-15
DE4115384C2 (en) 1994-07-07
CA2064497A1 (en) 1992-11-11
EP0512202A3 (en) 1993-09-01
JPH05157495A (en) 1993-06-22
CA2064497C (en) 1996-06-25
JP2675233B2 (en) 1997-11-12
EP0512202A2 (en) 1992-11-11
DE4115384A1 (en) 1992-11-12

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