Seeker head for a guided missile

The integrated cooling system in the seeker head addresses space and weight constraints by enhancing the performance of both infrared and radar detection units, optimizing space utilization and detection efficiency.

WO2026008240A1PCT designated stage Publication Date: 2026-01-08DIEHL DEFENCE GMBH & CO KG +2
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Patent Information

Application Number
PCT/EP2025/065610
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-07-03
Filing Date
2025-06-05
Publication Date
2026-01-08

AI Technical Summary

Technical Problem

Existing seeker heads for guided missiles face space and weight constraints due to competition between infrared and radar detection units, with prioritizing one detection unit reducing the capability or available resources for the other.

Method used

A seeker head design that integrates both infrared and radar detection units with a shared cooling device, allowing both units to operate efficiently by cooling them to optimal temperatures, thereby improving detection performance without competing for installation space.

Benefits of technology

The shared cooling system enhances the sensitivity and performance of both infrared and radar detection units, achieving improved detection capabilities while optimizing space utilization.

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Abstract

The invention relates to a seeker head (2) for a guided missile, comprising a detection device (3) which has a first detection unit (6) for detecting infrared radiation and a second detection unit (8) for detecting radar radiation. The detection device (3) has a cooling device (14) which is designed to cool at least one first detection element (7) of the first detection unit (6), in particular a detector, and at least one second detection element (9) of the second detection unit (8), in particular an antenna element.
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Description

[0001] seeker head for a guided missile

[0002] The invention relates to a search head for a guided missile, comprising a detection device which has a first detection device for detecting infrared radiation and a second detection device for detecting radar radiation.

[0003] Such seeker heads for guided missiles, which have detection devices for acquiring electromagnetic signals or radiation in the vicinity of the guided missile, are generally known from the prior art. For example, a first detection device is used to detect infrared radiation, for instance, by directing infrared radiation from outside the seeker head onto a detector inside the seeker head via an entrance window with imaging optics, in order to image or detect an object scene on the detector. It is also known that various radar signals in the form of radar radiation can be detected by the seeker head of the guided missile, for example, radar radiation emitted by a target.

[0004] Furthermore, it is known from the prior art that strict space and weight requirements apply to the design of seeker heads for guided missiles. The components of the seeker head or detection device, in particular the first and second detection units, compete for the available installation space. Depending on which aspect of the detection device is prioritized, or how strongly the different detection units are weighted relative to each other, favoring one detection unit can reduce the capability of the other, or leave fewer resources available for it.

[0005] For example, it is known to use a cooled [device] for the first detection unit.

[0006] To use a second detector to improve the detection result of the first detection device. However, such a design typically requires a comparatively large amount of installation space, so that correspondingly less space remains available for integrating the second detection device into the search head, and therefore the functionality or performance of the second detection device is reduced accordingly at the expense of the first detection device.

[0007] The invention is based on the objective of providing an improved search head for a guided missile, in which, in particular, the integration of different detection devices is improved.

[0008] The problem is solved by a search head with the features of claim 1. Advantageous embodiments are the subject of the dependent claims.

[0009] As described, the invention relates to a seeker head for a guided missile. The seeker head has a detection device comprising a first detection element and a second detection element. The first detection element is designed to detect infrared radiation. For example, the seeker head for the first detection element has an aperture or window through which infrared radiation from the environment can enter the seeker head. In particular, imaging optics can be provided that direct the infrared radiation from the environment onto a first detection element of the first detection element, which is preferably configured as a detector.

[0010] For example, an object scene can be imaged onto the detector by the imaging optics. The search head can therefore also be designed as a target guidance device, be part of a target guidance device for the guided missile, or incorporate such a device. In addition to the components described, the search head can further include a control unit or electronic unit designed to evaluate the detected radiation, i.e., infrared and radar radiation. This allows a control loop to be implemented, enabling the guided missile to be controlled or steered based on the detection results from the first and / or second detection devices.

[0011] Furthermore, as described, the search head includes the second detection unit, which is fundamentally designed for detecting radar radiation. For the purposes of this application, "radar radiation" is generally understood to mean radiation in a frequency range of approximately 1 GHz to approximately 40 GHz. The second detection unit thus enables the reception of an external radar signal in the radar frequency range, i.e., radar radiation, relative to the search head. As previously described with regard to infrared radiation, this signal can then be evaluated or measured and fed into a guidance loop or control loop. In other words, the first and second detection units represent different channels of the detection device.

[0012] The invention is based on the finding that the detection device has a cooling device configured to cool at least one first detection element of the first detection device, in particular a detector, and at least one second detection element of the second detection device, in particular an antenna element. An "antenna element" is understood here to be an element of the second detection device that is intended for receiving or detecting the radar radiation. In other words, the invention proposes that the cooling device be designed to cool both the first and the second detection devices.

[0013] The cooling device is therefore not used, as is known in the prior art, solely for improving the detection of infrared radiation, but enables cooling of both the at least one first detection element of the first detection device and the at least one second detection element of the second detection device. While space is required for providing or integrating the cooling device into the search head, this benefits not just one of the two detection devices, but both. Therefore, the detection of infrared radiation by the first detection device and the detection of radar radiation by the second detection device can be improved by the cooling device.Therefore, in this respect, the two devices do not compete for installation space; rather, the installation space allocated to the cooling device improves the detection result of the entire detection device, i.e., both the first detection device and the second detection device.

[0014] A cooling device suitable for cooling an IR detector or IR detector module can be used, for example. The cooling device is designed, for instance, to cool the first detection element and / or the second detection element, or a heat sink provided by the cooling device, to temperatures below 100 K.As will be described below with regard to the specific design of the second detection device, providing the cooling device to improve the sensitivity of the first detection device does not necessarily impair the performance of the second detection device; rather, the cooling device is also used for the second detection device, so that its performance can also be increased, especially compared to second detection devices typically used in search heads with actively cooled IR detectors.

[0015] In one embodiment of the search head, the cooling device may include a cooling unit configured to cool at least one heat sink, in particular a common heat sink, on which the first detection element and / or the second detection element are arranged. As already described, any number of first detection elements and / or second detection elements can be provided. The cooling unit cools, for example, a common heat sink on which the first detection element and the second detection element are arranged. For example, the first detection element may be arranged on a first side surface of the heat sink, in particular a side surface of the heat sink facing in the direction of flight.

[0016] The second sensing element can be arranged on a second side surface of the heat sink, for example, oriented perpendicular to the first side surface. It is also possible to provide more than one heat sink, with, for example, the first sensing element arranged on a first heat sink and the second sensing element on a second heat sink. The embodiment thus proposes spatial and functional integration, in particular such that the sensing elements can be arranged on the same heat sink and consequently also be heated or cooled to the same temperature.

[0017] In a further embodiment of the search head, the first and second detection elements can be arranged in a common cooling chamber of the cooling device, in particular a Dewar flask. The cooling chamber is, for example, bounded by a common housing. Accordingly, the detection elements of the detection devices are integrated into a common cooling chamber. Specifically, no additional space is required, since the detection devices share the cooling chamber. While the system proposed herein may require more space compared to a single detector or detection device, the space requirement is less than that for two separate detection devices with their own separate cooling systems.In particular, the cooling element can be located in the described cooling room, specifically the shared cooling element on which all detection elements are arranged.

[0018] The described search head can be further developed such that at least one second detection element is configured as a superconducting quantum interference device or incorporates at least one superconducting quantum interference device. A superconducting quantum interference device is understood to be, in particular, a so-called SQUID (superconducting quantum interference device) or SQIF (superconducting quantum interference filter). The SQIF can incorporate a SQU ID array. The superconducting quantum interference device is thus used as an antenna element to detect and acquire radar radiation or radar signals. Consequently, the second detection element can acquire a radar signal or radar radiation and, for example, output a voltage signal. The voltage signal can be an analog signal. The voltage signal can then be digitized and analyzed.

[0019] In particular, this enables the second detection unit to detect radar radiation with significantly greater sensitivity than is possible with conventional radar antennas. The integration of such a superconducting quantum interference device is made possible primarily by the fact that the cooling system, which is usually only provided for the first detection unit, can also be used for the second. This allows the superconducting quantum interference device to operate because the cooling system can cool it down to a temperature range in which it exhibits superconductivity. In other words, the cooling system can be used to cool the superconducting quantum interference device below its critical temperature.Furthermore, the search head can be configured to include at least two superconducting quantum interference devices designed for different frequency ranges and configured to detect radar signals or radar radiation in different frequency ranges, particularly in a frequency range of 1–40 GHz. In other words, a superconducting quantum interference device can be provided for each of the different frequency ranges, designed to detect radar signals or radar radiation in that frequency range. The combination of the different superconducting quantum interference devices thus results in the described frequency range, in which the second detection device is generally configured to detect radar radiation. The superconducting quantum interference devices can, for example, have different, and in particular non-commensurate, diameters. The pattern or...The selection of superconducting quantum interference devices thus allows for a comparatively broad frequency range to be covered. Specifically, it is possible to switch between individual superconducting quantum interference devices to detect radar radiation of different frequencies.

[0020] In a further embodiment, the search head can be further developed such that the at least one superconducting quantum interference device of the at least one second detection element comprises at least one high-temperature superconductor. The use of high-temperature superconductors eliminates the need for a complex cooling system and allows for the use of a comparatively simpler cooling system. For example, high-temperature superconductors can be used that can operate within a temperature range achievable by a cooling system designed to cool the first detection element of the first detection device. In other words, a cooling system for an IR detector can advantageously be used to achieve a temperature range in which the high-temperature superconductor exhibits superconducting properties.Specifically, the cooling device used for the IR detector allows the IR detector and the superconducting quantum interference device to be cooled to a temperature below the critical temperature of the high-temperature superconductor.

[0021] Advantageously, a synergy can thus be achieved, since in this

[0022] Within this temperature range, the first high-performance detection device can be operated. Similarly, by operating below the critical temperature for the superconducting quantum interference device, it can be operated in a superconducting state and therefore exhibit the previously described properties, particularly regarding its high sensitivity in detecting radar radiation.

[0023] In a specific embodiment, the high-temperature superconductor can comprise or be made of YBaCuO, and / or the at least one detection element can comprise or be made of HgCdTe or InSb, or a superlattice detector. In principle, various high-temperature superconductors can be used. Advantageously, these have a critical temperature in the range of 100 K, for example, 80 K to 100 K, and specifically 85 K to 90 K.

[0024] As described at the outset, the first detection device typically includes an entry window through which the infrared radiation can be guided into the search head. Several alternatives are possible regarding the design of the second detection device. In one embodiment, the second detection device can have at least one waveguide configured to guide radar radiation or a radar signal through a housing wall to the superconducting quantum interference device located within the housing.

[0025] In another embodiment, the housing can have an aperture for radar radiation or the radar signal, wherein the second detection device is configured to detect the radar radiation or the radar signal through the aperture. In the first described embodiment, a radar antenna is used, for example, mounted in the area of ​​a missile's fuselage, to detect or capture the radar radiation in the vicinity of the missile and thus outside the housing in which the superconducting quantum interference device is located. The detected or captured radar signal or radar radiation is then guided to the superconducting quantum interference device via the waveguide. The housing or housing wall is understood to be, in particular, the housing that delimits the cooling compartment, for example, the Dewar flask.The waveguide can, for example, be guided through the housing wall by means of a coaxial cable known per se, so that the radar radiation or radar signal can be guided or transmitted from outside the Dewar flask to the superconducting quantum interference device inside. In the second described embodiment, the second detection device, in particular the superconducting quantum interference device, can be arranged at an aperture in the housing wall such that radar radiation or a radar signal can be detected through the aperture. In this case, the second detection device can be made particularly compact, since an additional radar antenna and a waveguide as well as a housing feedthrough are not required. The aperture is designed such that it allows radar radiation or radar signals to penetrate into the interior of the housing or the cooling device in which the second detection element, i.e., the superconducting quantum interference device, is located.in particular the superconducting quantum interference device is arranged.

[0026] The superconducting quantum interference device can therefore also be used directly as a compact broadband RF antenna. The superconducting quantum interference device can comprise an array; specifically, it can form a SQIF with an array of SQUIDs, or a SQUID array. The superconducting quantum interference device is susceptible to the magnetic component of the electromagnetic field of the radar radiation or signal. This significantly reduces the antenna dimensions compared to antenna systems that respond to the electrical component of the rock.

[0027] The lower noise level of the superconducting quantum interference device, combined with the small aperture size required and the high bandwidth, is therefore particularly advantageous for use on so-called "SWaP-critical" ("size, weight, and power") platforms. For this purpose, it may be necessary to connect the cooling system directly to the platform's outer shell or the missile's fuselage in order to position the superconducting quantum interference device there. For example, an integrated detector cooling assembly (IDCA) can be adapted to position the superconducting quantum interference device so that radar signals or radiation entering through the aperture can be detected by the device.

[0028] In addition to the described search head, the invention also relates to a guided missile comprising such a search head. For the purposes of this invention, guided missiles can also include unmanned aerial vehicles, in particular so-called "UAVs". In such UAVs, the search head can, for example, be used for reconnaissance, or, in other words, a UAV can be equipped with a sensor unit for reconnaissance purposes, which is constructed like the search head.The invention further relates to a method for operating a seeker head for a guided missile, comprising a detection device which has a first detection unit for detecting infrared radiation and a second detection unit for detecting radar radiation, wherein the detection device has a cooling device by means of which at least one first detection element of the first detection unit, in particular a detector, and at least one second detection element of the second detection unit, in particular an antenna element, is cooled.

[0029] The described procedure can be carried out in detail with the previously described search head or guided missile.

[0030] All the advantages, details and features described in relation to the seeker head are therefore also transferable to the guided missile and the procedure.

[0031] The invention is explained below with reference to exemplary embodiments and the figures. The figures are schematic representations and show:

[0032] Fig. 1 shows a schematic representation of a guided missile;

[0033] Fig. 2 shows a schematic representation of a search head according to a first embodiment; and

[0034] Fig. 3 shows a schematic representation of a search head according to a second embodiment.

[0035] Fig. 1 shows a guided missile 1 comprising a seeker head 2 with a detection device 3. By way of example, the guided missile 1 is also shown with an engine 4 and wings 5. The guided missile 1 can be controlled, for example, in a manner known per se, by means of control signals generated by the seeker head 2, in order to locate a target. The seeker head 2 is described in detail in two exemplary embodiments with reference to Figs. 2 and 3. Such a seeker head 2, as described in Figs. 2 and 3, can therefore be used in the guided missile 1 of Fig. 1.

[0036] Fig. 2 shows a first embodiment of a search head 2 with a detection device 3. The detection device 3 comprises a first detection unit 6 with a first detection element 7 and a second detection unit 8 with a second detection element 9. The detection elements 7, 9 can represent individual elements or so-called arrays, i.e., groupings of individual elements. The first detection unit 6 is configured, as indicated by an arrow 10, for detecting infrared radiation. The infrared radiation enters a housing 12 of the detection device 3 through an entrance window 11. The first detection unit 6 can also include imaging optics (not shown) by which the infrared radiation can be imaged onto the first detection element 7. In particular, an object scene in front of the guided missile 1 can thus be detected.The image is projected onto the first detection element 7, specifically an infrared detector, in front of the search head 2. Not shown is that the first detection element 7 is connected to a control unit or electronics unit designed to evaluate the signals generated by the first detection element 7 in response to the detected infrared radiation.

[0037] The second detection device 8 is designed to detect radar radiation, in particular radar signals in a frequency range from 1 GHz to 40 GHz. In the first embodiment, shown in Fig. 2, the second detection element 9, which is specifically configured as a superconducting quantum interference device, for example as an SQIF, comprising a SQUID array, is connected by means of a waveguide 13 to a radar antenna, not shown in detail, located outside the housing 12. The waveguide 13 can, for example, be designed in the form of a coaxial cable and carry the radar signal from the radar antenna through the housing 12 or a housing wall of the housing 12.

[0038] The detection elements 7 and 9 can be connected to a computing device, control device, or electronic unit (not shown in detail). The signals generated by the detection elements 7 and 9 can be digitized, evaluated, and used to generate guidance signals for the guided missile 1, thereby guiding the missile 1 to a target.

[0039] The search head 2 further comprises a cooling device 14. The cooling device 14 includes, for example, a cooling unit 15 and a heat sink 16. In the illustrated embodiments, the housing 12 can be a Dewar flask in which the detection elements 7, 9 are arranged. The housing 12 therefore defines a cooling chamber in which the detection elements 7, 9 are arranged. Figures 2 and 3 show that the detection elements 7, 9 are arranged on a common heat sink 16. It is also possible for each detection element 7, 9 to have its own heat sink 16, or for the heat sink 16 to be subdivided accordingly. It is evident that both detection elements 7, 9 are thus located within the cooling device 14, i.e., within the housing 12 and on the heat sink 16. The detection elements 7, 9 can therefore both be cooled by the cooling device 14, in particular to a specific temperature range or to a defined temperature.

[0040] Firstly, this improves the operation of the first detection device 6, in particular the first detection element 7, since the first detection element 7, which is designed, for example, as an infrared detector, can be cooled for operation, thus improving the performance of the first detection device 6. For example, the first detection element can comprise HgCdTe or InSb or a supergrid detector and benefits in particular with regard to the sensitivity in the detection of infrared radiation from cooling by the cooling device 14.

[0041] The cooling device 14 also improves the operation of the second detection device 8, which is designed for detecting radar radiation. Both detection devices 6 and 8 can therefore use the same cooling device 14 and thus be integrated, at least partially. The detection device 3 of the search head 2 therefore does not have detection devices 6 and 8 that compete with each other for space; instead, the space is shared, achieving a synergy effect, particularly with regard to the cooling device 14. Specifically, completely separate detection devices 6 and 8 are not proposed; rather, the cooling device 14 is used by both detection devices 6 and 8. Compared to individual detection devices 6 and 8, which might have their own cooling devices, this saves space.

[0042] As described, the second detection element 9 is specifically designed as a superconducting quantum interference device. The cooling device 14 is configured to cool the heat sink 16, and thus also the second detection element 9, below the critical temperature for the superconducting quantum interference device. Specifically, the cooling device 14 cools the second detection element 9, and thus also the first detection element 7, below 100 K, more specifically below 90 K, preferably to or below 85 K. For example, a high-temperature superconductor, such as YBaCuO, can be used as the superconducting quantum interference device of the second detection element 9.

[0043] Accordingly, the cooling device 14 ensures that the first detection element 7 is sufficiently cooled to be sensitive enough to detect infrared radiation. Furthermore, the cooling device 14 maintains the temperature of the second detection element 9 below the critical temperature for the superconducting quantum interference device, enabling the second detection element 8 to detect defined radar radiation with high sensitivity.

[0044] In contrast to the connection of the second detection element 9 with a waveguide 13 described in Fig. 2, the seeker head 2, shown in a second embodiment in Fig. 3, does not have a waveguide 13. Instead, an aperture 17 is provided in the housing 12, allowing radar radiation to pass into the housing 12, as indicated by arrow 18. In other words, the second detection element 9 can be arranged in the seeker head 2 such that radar radiation can be detected by the second detection element 9 through the aperture 17. The second detection element 9, i.e., in particular the superconducting quantum interference device, can be arranged in the region of the outer skin of the guided missile 1 such that radar radiation can pass through the aperture 17 and be detected by the second detection element 9.

[0045] In this embodiment, the detection device 3 or the second detection device 8 can be designed to be particularly compact, since additional radar antennas and waveguides can be omitted.

[0046] As shown in Figures 2 and 3, the detection elements 7 and 9 are arranged on different sides of the heat sink 16. For example, the first detection element 7 is arranged on a first side of the heat sink 16, which can be referred to as the end face, and which, for example, points in the direction of flight of the guided missile 1. The heat sink 16 can, for example, be cuboid in shape. The second detection element 9 can be arranged on a lateral surface of the heat sink 16. It is also possible for several second detection elements 9 to be arranged on different sides of the heat sink 16. In the described embodiments, the second detection device 8 can have several second detection elements 9 designed for different frequency ranges. In combination, the different detection elements 9 can cover the described frequency range from 1 GHz to 40 GHz.For example, the control unit of the search head 2 can switch the different second detection elements 9 in order to detect radar signals or radar radiation in the different frequency ranges.

[0047] The advantages, details, and features described with reference to Figures 1-3 can be combined, interchanged, and transferred to one another as desired. The method described herein can be carried out with the guided missile 1 or the described seeker heads 2. The description is therefore also fully transferable to the method.

[0048] Reference symbol list Guided missile Seeker head Detection device Engine Wing First detection device First detection element Second detection device Second detection element Arrow Entrance window Housing Shaft guide Cooling device Cooling machine Heat sink Aperture Arrow

Claims

Patent claims 1. Search head (2) for a guided missile (1), comprising a detection device (3) having a first detection unit (6) for detecting infrared radiation and a second detection unit (8) for detecting radar radiation, characterized in that the detection unit (3) has a cooling device (14) configured to cool at least one first detection element (7) of the first detection unit (6), in particular a detector, and at least one second detection element (9) of the second detection unit (8), in particular an antenna element.

2. Search head (2) according to claim 1, characterized in that the cooling device (14) has a cooling machine (15) which is designed to cool at least one cooling body (16), in particular a common cooling body (16), on which the first detection element (7) and / or the second detection element (9) are arranged.

3. Search head (2) according to claim 1 or 2, characterized in that the first detection element (7) and the second detection element (9) are arranged in a common cooling chamber of the cooling device (14), in particular a Dewar vessel.

4. Search head (2) according to one of the preceding claims, characterized in that the at least one second detection element (9) is designed as a superconducting quantum interference device or has at least one superconducting quantum interference device.

5. Search head (2) according to claim 4, characterized in that the second detection device (8) has at least two sensors for different frequency ranges It features designed superconducting quantum interference devices and is designed to detect radar signals in different frequency ranges, especially in a frequency range of 1-40GHz.

6. Search head (2) according to claim 4 or 5, characterized in that the at least one superconducting quantum interference device of the at least one second detection element (9) comprises at least one high-temperature superconductor.

7. Search head (2) according to claim 6, characterized in that the high-temperature superconductor comprises YBaCuO and / or that the at least one first detection element (7) comprises HgCdTe or InSb or a superlattice detector.

8. Search head (2) according to one of the preceding claims, characterized in that the second detection device (8) has at least one waveguide (13) configured to guide a radar signal through a housing wall to the superconducting quantum interference device arranged in the housing (12), or that the housing (12) has an aperture (17) for radar radiation, wherein the second detection device (8) is configured to detect radar radiation through the aperture (17).

9. Guided missile (1) comprising a seeker head (2) according to any of the preceding claims.

10. Method for operating a seeker head (2) for a guided missile (1), comprising a detection device (3) having a first detection unit (6) for detecting infrared radiation and a second detection unit (8) for detecting radar radiation, characterized in that the detection device (3) has a cooling device (14) by means of which at least one first detection element (7) of the first detection unit (6), in particular a detector, and at least one second detection element (9) of the second detection unit (8), in particular an antenna element, is cooled.

Citation Information

Patent Citations

  • Unmanned, air-borne reconnaissance drone

    DE19714539A1

  • superconducting element

    DE4010489A1

  • Advanced cooling system using throttled internal cooling passage flow for a window assembly, and methods of fabrication and use thereof

    US11473846B1

  • Multimode short wavelength infrared and radio-frequency seeker

    US20150323287A1

  • Missile Seeker Limited Scan Array Radar Antenna

    US20220074710A1