US20220026181A1

US20220026181A1 - Method for protecting moving or stationary objects from approaching laser-guided threats

Info

Publication number: US20220026181A1
Application number: US17/311,479
Authority: US
Inventors: Thomas Macher; Lukas Grundner
Original assignee: Rheinmetall Waffe Munition GmbH
Current assignee: Rheinmetall Waffe Munition GmbH
Priority date: 2018-12-10
Filing date: 2019-11-08
Publication date: 2022-01-27
Also published as: EP3894779A1; WO2020120041A1; DE102018131524A1

Abstract

The aim of the invention is to enable, in a simple manner, the protection of moving or stationary objects from laser-guided threats, in particular from laser-guided threats approaching the object from above. This aim is achieved, according to the invention, in that active masses of a corresponding number of decoys are ignited in a specifiable height range to the windward side of the object to be protected such that the decoy cloud(s) forming in this height range is/are moved by the wind force acting thereon over the object to be protected and subsequently conceal said object.

Description

FIELD

The invention relates to a method for protecting moving or stationary objects from laser-guided threats approaching the object. The invention relates in particular to the protection against laser-guided threats approaching from above (e.g. laser-guided missiles, glide bombs, laser-guided bombs, etc.).

BACKGROUND

Laser-guided threats have a laser seeker made of photodiodes. The photodiodes only register a specific wave spectrum of monochromatic laser light. In order for the target to be recognized by the sensor, it must be marked with a laser beam from the ground or from the air until it is hit. The missile needs visual contact with the target during the final phase of the flight.
DE 196 04 745 C1 already describes a method and an arrangement for deceiving end-phase guided ammunition. The target is spared in that a laser beam is sent toward this ammunition, which directs the ammunition onto a new flight path.
A method for protecting ships from end-phase guided missiles and a device for carrying out this method are known from DE 103 46 001 B4. In the known method, a computer is used to determine an optimal decoy pattern from the missile data (direction of approach, distance, and speed of the missile), the ship's own data (speed, direction of travel, and roll and pitch movements of the ship), as well as the wind data (wind speed and wind direction). On the basis of this decoy pattern, the number of decoys required, their firing angle, and their delay time until their active mass is ignited is determined. A decoy launcher is subsequently activated on the basis of these values, which decoy launcher fires the determined number of corresponding decoys with a programmable delay time.
The active masses of the decoys are then deployed at a specified height in the immediate surroundings of the ship in order to generate a decoy structure which then moves the decoy away from the ship while changing direction.
DE 10 2015 002 737 A1 and DE 10 2010 032 458 A1 describe devices for providing a decoy in front of radar-guided seeker heads. A device and a method for generating an effective smoke screen can be found in WO 2012/028257A1.
DE 11 2010 003 767 T5 discloses a laser-guided missile with a dual mode SAL/IR seeker head with a common line of sight. With the help of an IR detector, the incident infrared energy is recorded in order to generate at least one IR steering signal. At least one SAL steering signal is produced with a position-sensitive SAL detector.
DE 10 2015 015 938 A1 also assumes that IR decoys are conceptually ineffective against laser-guided missiles.

SUMMARY

The invention is based on the object of specifying a method with which it is possible in a simple manner to protect moving objects, such as ships or other military vehicles, but also stationary objects such as buildings, from approaching laser-guided missiles.
According to the invention, this object is achieved by the features of claim 1. Further, particularly advantageous embodiments of the invention are disclosed in the dependent claims.
The invention is substantially based on the idea that visual contact with the target is interrupted during the final phase of the flight of a laser-guided ammunition or missile, i.e. a threat. For this purpose, a decoy cloud is generated that conceals the ship from above or, if necessary, envelops it, i.e. encloses it, at least during the final phase.
As a result of this idea, the decoy launcher is aligned in such a way that the corresponding activation of the active masses of the decoys takes place above an object to be protected and in a specifiable height range to the side of the object to be protected. The deployment is carried out taking into account the wind direction. After activating the active masses of the decoys in this height range, the forming decoy cloud(s) is/are then moved over the object to be protected by the wind force acting thereon and subsequently conceal said object. This breaks the line of sight to the target.
It has proven to be advantageous if the individual decoys are fired in a plurality of volleys, which together form a sequence, in order to completely conceal the object with a decoy cloud. The decoys of each volley are arranged in rows. The time interval between the volleys is chosen so that the individual volleys can be shot in the same spatial region, i.e. the wind has already shifted the decoy partial cloud of the previous volley toward the object before the decoys of the new volley are activated.
The concealing of the object can also be implemented, as already suggested in DE 10 2015 002 737 A1, by a plurality of launchers (decoy launchers) of a decoy launching system (Täuschkörperwurfanlage—TKWA).
Another advantage of this method is that problems caused by decoys falling back on the object (e.g., not completely burned off flares, etc.) can be excluded. These fall into the water or onto the ground next to the object to be protected.
The aim of the invention is to enable, in a simple manner, the protection of moving or stationary objects from laser-guided threats, in particular from laser-guided threats approaching the object from above. This aim is achieved, according to the invention, in that active masses of a corresponding number of decoys are ignited in a specifiable height range to the windward side of the object to be protected such that the decoy cloud(s) forming in this height range is/are moved by the wind force acting thereon over the object to be protected and subsequently conceal said object.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details and advantages of the invention emerge from the following embodiment described with reference to drawings. In the drawings:

FIGS. 1a, 2a, and 3a are schematic front views of a ship emitting decoy volleys to generate a decoy cloud according to the invention over the ship and FIGS. 1b , 2 b, and 3 b are the top views of FIGS. 1a, 2a, and 3a of the ship which is shown schematically.

DETAILED DESCRIPTION

In FIGS. 1a to 3b , 1 denotes a ship in each case, which is only shown schematically. The ship 1 is provided with at least one “top attack” sensor 2, which can detect a laser beam 8 directed from above onto the ship 1 in good time so that defensive measures according to the invention can be taken before the missile 3 hits the ship 1. The laser beam 8 does not necessarily have to be directed at 90° from above onto the ship 1. If the laser beam 8 lies in the detection region 9 of the “top attack” sensor 2, it is detected accordingly and countermeasures according to the invention can be taken.
For this purpose, a computer (not shown) determines an optimal decoy pattern 100 (FIG. 3b ; for calculating decoy patterns, cf. also DE 103 46 001 B4 or WO 2012/028257 A1) from the missile or threat data (distance, speed), the ship data (direction of movement, speed of movement), and the wind data (direction and speed). The method for determining the optimal decoy pattern can be optimized in that bearing data, for example elevation and azimuth angles of the threat (direction of the laser beam 8), are also taken into account.
A measurement of the elevation and azimuth angle of the laser beam 8 can be dispensed with if a target assignment by the laser beam 8 takes place from above, so that the elevation angle is 90° and the azimuth angle is irrelevant.
From this decoy pattern 100, the number of decoys 4 required, their firing angle in each case, and their delay time up to the ignition of the corresponding active mass is then determined.
The decoys 4 can be decoys with an infrared/smoke signature.
Subsequently, on the basis of these values, at least one decoy launcher 5 is activated, which then fires the number of corresponding decoys 4 determined in a timely manner. For this purpose, the at least one decoy launcher 5 is aligned in such a way that the active mass of each decoy 4 is ignited in a specifiable height range on the windward side of the ship 1 to be protected and the decoys 4 generate a decoy cloud corresponding to the decoy pattern 100 after their active mass has been ignited. This decoy cloud is moved over the ship 1 by the wind 6 to be blown toward the ship 1 and conceals it, so that the ship 1 is no longer recognized as such by an approaching laser-guided threat 3 and a target assignment of the threat 3 becomes impossible.
It has proven to be advantageous if not the entirety of the decoy cloud required to cover the ship 1 is produced outside the ship region and if a subsequent waiting process until the decoy cloud has pushed itself over the ship 1 by the wind 6 does not take place, but rather that a plurality of decoy partial clouds are produced in succession which are composed above the ship 1 to form a decoy cloud covering the ship 1.
For this purpose, a plurality of volleys of decoys 4 are fired in succession. In the embodiment shown, five volleys I-V are fired to cover the ship 1, the firing of the first volley I being shown schematically in FIGS. 1a and 1b , the firing of the second volley II being shown schematically in FIGS. 2a and 2b , and the firing of the fifth volley V being shown schematically in FIGS. 3a and 3 b.
In each of the volleys I-V, three (exemplary) decoys 4 are fired at the same time, which are arranged in a row (cf. FIGS. 1b, 2b, and 3b ) and which, after their active masses are activated, generate a decoy partial cloud in each case.
As can be seen from FIG. 1b-3b , the wind 6 blows obliquely from the front in the embodiment shown, so that, viewed in the wind direction, the ship 1 has a relatively narrow width B (B is also referred to below as projected width). The decoy cloud for concealing the ship 1 can therefore also be relatively narrow, which should be taken into account when selecting the number of decoys 4 per volley I-V and when selecting the number of volleys I-V.
The time interval between the volleys I-V fired from the decoy launcher 5 is now selected in such a way that the individual volleys I-V can always be fired into the same region 7 on the windward side, i.e. the time interval between the volleys I-V must be chosen so that before the arrival of the decoys 4 of a new volley II-V, the decoy partial cloud of the previous volley I-IV was shifted by the wind 6 to the direction of the ship 1.
The number of volleys I-V of decoys 4 is selected in such a way that after firing all decoys 4 in a sequence, it results in a homogeneous and complete concealing of the ship 1 (FIG. 3b ).
In order to implement an effective solution for completely covering the ship 1, it is required to dynamically calculate the projected width B of the ship 1 in the direction of the wind 6. The width of the row of a volley I-V consisting of the decoys 4 results from the previously calculated projected width B of the ship 1.
The effectiveness of the decoy cloud can be checked at the same time with the “top attack” sensor 2, since this sensor 2 may then no longer perceive the laser beam 8 or, possibly, does not detect the scattered radiation thereof.
The method according to the invention is of course not limited to the protection of ships 1 or other vehicles, but can also be used to protect buildings etc. from approaching laser-guided threats 3.

LIST OF REFERENCE SIGNS

1 Ship, object
2 “Top attack” sensor, sensor
3 Missiles/threats
4 Decoy
5 Decoy launcher
6 Wind
7 Region outside the object (windward side)
8 Laser beam or laser source
9 Detection region of “top attack” sensor
100 Decoy pattern

Claims

1.-10. (canceled)

11. A method for protecting moving or stationary objects from a laser-guided threat approaching the object, comprising:

igniting active masses of at least one decoy in a specifiable height range on the windward side away from the object to be protected, wherein after the active masses are ignited, a decoy cloud that is forming moves over the object to be protected by the wind.

12. The method according to claim 11, wherein a computer determines an optimal decoy pattern from threat data of the approaching laser-guided threat and from wind data in the surroundings of the object.

13. The method according to claim 11, wherein object data such as the direction of movement and the speed of movement of the object are taken into account.

14. The method according to either claim 12, wherein a number of the required decoys, their firing angle, and their delay time until their active mass is ignited, are determined from this data.

15. The method according to claim 14, wherein on the basis of these values, at least one decoy launcher is triggers, which fires the determined number of corresponding decoys, so that a resulting decoy cloud is produced which completely conceals the object.

16. The method according to claim 12, wherein the threat data are the distance and speed, possibly an elevation angle and an azimuth angle of the laser-guided threat.

17. The method according to claim 12, wherein the wind data are wind direction and wind speed.

18. The method according to claim 11, wherein to completely conceal the object by a decoy cloud, the individual decoys are fired in a plurality of volleys and the active charges of the decoys of each volley are activated at the same time.

19. The method according to claim 18, wherein the decoys of each volley are arranged in rows.

20. The method according to claim 19, wherein the time interval between the volleys is selected in such a way that the wind has already shifted the decoy partial cloud of the previous volley in the direction of the object, before the decoys of the following volley (II-V) are shot into the same windward side region and their active charges are activated there.