(51) Int Cl.: H01Q 1/28 ( ) H01Q 1/42 ( ) H01Q 1/02 ( )

Transcription

1 (19) TEPZZ 878Z9B_T (11) EP B1 (12) EUROPEAN PATENT SPECIFICATION (4) Date of publication and mention of the grant of the patent: Bulletin 17/01 (21) Application number: (22) Date of filing: (1) Int Cl.: H01Q 1/28 (06.01) H01Q 1/42 (06.01) H01Q 1/02 (06.01) (86) International application number: PCT/GB/01141 (87) International publication number: WO 11/ ( Gazette 11/03) (4) A RADOME AND METHOD OF COOLING RADAR COMPONENTS RADOM UND VERFAHREN ZUR KÜHLUNG VON RADARKOMPONENTEN RADÔME ET PROCÉDÉ POUR REFROIDIR DES COMPOSANTS DE RADAR EP B1 (84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR () Priority: GB (43) Date of publication of application: Bulletin 11/47 (73) Proprietor: Samarai, Faris Aberdeen AB2 0PD (GB) (72) Inventor: Samarai, Faris Aberdeen AB2 0PD (GB) (74) Representative: Cameron, Stewart Cameron Intellectual Property 69 St. Vincent Street Glasgow G2 TF (GB) (6) References cited: JP-A Carlo Kopp: "AEW&C - Phased Array Technology Parts 1 & 2", Australian Aviation, 1994 INTERNET ARTICLE, June 08 (08-06-), pages P.1-11, XP , Retrieved from the Internet: URL: 2/ ml [retrieved on ] HEED M: "The ERIEYE phased array antenna - from a systems viewpoint", PHASED ARRAY SYSTEMS AND TECHNOLOGY, 00. PROCEEDINGS. 00 IEEE INTE RNATIONAL CONFERENCE ON DANA POINT, CA, USA 21-2 MAY 00, PISCATAWAY, NJ, USA,IEEE, US, 21 May 00 ( ), pages P , XP004616, DOI:.19/PAST ISBN: NEIL CHAMBERLAIN ET AL: "The UAVSAR Transmit / Receive Module", AEROSPACE CONFERENCE, 08, IEEE, PISCATAWAY, NJ, USA, 1 March 08 ( ), pages P.1-1, XP , ISBN: CHAMBERLAIN N ET AL: "The UAVSAR phased array aperture", Pasadena, CA : Jet Propulsion Laboratory, National Aeronautics and Space Administration, 06 INTERNET ARTICLE, 11 March 06 ( ), 11 March 06 ( ), page P.1-12, XP ,, Big Sky, MT Retrieved from the Internet: URL: [retrieved on ] Note: Within nine months of the publication of the mention of the grant of the European patent in the European Patent Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the Implementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). Printed by Jouve, 7001 PARIS (FR)

2 1 EP B1 2 Description [0001] The present invention relates to a radome particularly, but not exclusively, a radome for mounting on an aircraft s fuselage in order to protect and cool the aircraft s radar scanner components. A method of cooling radar scanner components in order to maintain the working temperature of the radar scanner components is also provided. [0002] Radar systems are used in a number of different scenarios in order to retrieve information such as the range, altitude, direction, speed etc. of moving objects such as aircrafts, ships, land based vehicles etc. or fixed objects such as terrain. [0003] Radar systems are typically housed in a radome which is designed to streamline and protect the working components of the radar whilst minimising any interference on the returned signal. [0004] A number of different radar systems are available; however, there has recently been an increasing tendency to use ESA (Electronically Scanned Array; also known as Active Phased Array) based systems due to a number of advantages such systems provide. One of the important differences between the mode of operation of ESA radar systems and previous systems is that ESA systems use their antenna to carry out transmission / reception of the radar signal rather than a discrete transmitter / receiver. This has some significant advantages over previous systems; however, it does produce the side effect that the antenna heats up more during use than in previous radar systems. If left unchecked, this additional heat factor can contribute to a deterioration in equipment performance and or malfunction. Some form of maintaining the scanner components at working temperature in such systems is therefore required. [000] One way of maintaining the working temperature of the radome is to use coolant based refrigeration techniques or recirculation of pressurised air within the housing in order to maintain an optimum temperature within the radome. However, such systems require undesirably complex compression and routing systems if they are to be installed in an aircraft. An example of an air-cooled system is shown in "The UAVSAR Phased Array Aperture" catalogue ref XP of the Jet Propulsion Laboratory in Pasadena, California. [0006] According to the present invention as defined in claim 1 there is provided a radome comprising: a radar component housing; a ram air inlet provided in the radar component housing; and a ram air outlet provided in the radar component housing such that when the radome is installed on the body of a moving craft, air flow relative to the craft will enter the housing by way of the ram air inlet, circulate within the housing, and exit the housing by way of the ram air outlet in order to cool radar components within the radar component housing, characterised in that the ram air inlet is provided aft of the ram air outlet in order to encourage circulation of air within the radome housing. The radome may be adapted to be mounted on an aircraft fuselage. The position of the ram air inlet and ram air outlet may be such that a transmission / reception antenna within the radome housing is cooled by the air circulating within the radome housing. [0007] Optionally, the ram air inlet comprises a hole through a wall of the radome housing and a recessed flap surface in the radome housing. Optionally, the ram air inlet is provided in a side wall of the radome housing. A removable filter element may also be provided at the ram air inlet. [0008] Optionally, the ram air inlet comprises a NACA duct in a wall of the radome housing. Preferably, the ram air outlet is provided in a lower wall of the radome housing. [0009] Optionally, the ram air outlet is provided with a socket which allows it to be connected to a suction device. The socket may comprise a bayonet connection. For ground operation, this allows a suction device to induce a flow through the radome to provide the necessary flow of air in the radome. A recirculation fan may also be provided to improve circulation of air within the radome housing. [00] According to the present invention as defined in claim 13 there is also provided a method of cooling radar components, the method comprising the steps of:- housing radar components in a radar housing; providing a ram air inlet in a wall of the radar housing; providing a ram air outlet in a wall of the radar housing; mounting the radar housing to a craft; such that, when the craft moves, ram air flows into the air inlet, circulates around the housing to cool the radar components within the housing, and then exits the radar housing by way of the ram air outlet, characterised in that the method further comprises the step of encouraging circulation of air within the radar component housing by providing the ram air inlet aft of the ram air outlet. [0011] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:- Fig. 1 is a schematic plan view from beneath a radome according to the present invention; and Fig. 2 is a schematic side view of the radome of Fig. 1 where the radome is installed on the belly of an aircraft s fuselage. [0012] A radome, generally designated has a radar housing 12 which has a streamlined profile in order to reduce drag on the aircraft. The radar housing 12 is at- 2

3 3 EP B1 4 tached to the underside of an aircraft s fuselage 14 and protects the radar scanner components 16 therein. The radar scanner components may include e.g. a transmission / reception antenna and a processor which are linked to the aircraft avionics in order to provide an integrated radar system. [0013] A NACA duct ram air inlet 18 (best seen in Fig. 1) is provided through one side of the radar housing 12. The ram air inlet 18 in the embodiment shown comprises a hole with a recessed flap 18 to receive the oncoming airflow (labelled "IN") such that the air IN enters the radar housing 12. [0014] A ram air outlet (best seen in Fig. 2) is provided on the bottom of the radar housing 12. The ram air outlet in the embodiment shown comprises a hole having a scooped flap which is directed away from the oncoming airflow (labelled "OUT") in order to encourage air circulating within the radar housing 12 to exit the radar housing 12. A removable filter element (not shown) may also be provided at the ram air inlet. This is useful, to filter out any unwanted contaminants in the incoming air flow. For example, in low level operations, the surrounding air may have a significant salt content; however, the removable filter is able to filter this out in order to prevent long term damage to the radar scanner components. [001] The air inlet 18 is provided to the side of the radar scanner components 16 and the outlet is provided forward of the radar scanner components 16. This ensures that the air entering the inlet must circulate within the radar housing 12 before it exits the outlet and prevents the air simply entering the inlet 18 and passing straight through the radar housing 12 and out the outlet without circulating over the radar scanner components 16. This forces circulation of the air within the radome 12 thereby ensuring optimum cooling within the radome. [0016] In the embodiment shown, a recirculation fan 22 (Fig. 2) is also mounted in the radar housing 12. This may or may not be necessary; however, if provided it may further improve the circulation of air within the radar housing 12. The recirculation fan 22 may be driven in order to optimise recirculation of air in the housing 12. [0017] In use, on an aircraft, as the aircraft moves through the air, ram air IN is forced into the radar housing 12 through the ram air inlet 18. The dynamic air pressure at the inlet 18 may assist with this. As the ram air enters the radar housing 12 it circulates around the inside of the housing 12. The distribution of the circulating air in the radar housing 12 can be improved by the recirculation fan 22, if required. Because ram air is typically relatively cool (particularly when the aircraft is flying in cooler, higher air) the flow of the air over the radar scanner components 16 cools those components. After circulating within the radar housing 12, the air will have been warmed by the radar scanner components 16 (in particular the antenna) and will exit the radome housing 12 by way of the ram air outlet. In this regard, it should be noted that the ram air inlet 18 is positioned aft of the ram air outlet such that the air entering the ram air inlet 18 must pass over the radar scanner components 16 before it can exit the ram air outlet. The aft facing scoop of the ram air outlet and the motion of the air flowing over the outer surface of the radome 12 results in a vacuum effect being created at the ram air outlet to encourage the warmed air to be expelled from the ram air outlet as the flow of air, labelled OUT in the Figs. [0018] The invention therefore provides an improved system of cooling components of a radar scanner in order to maintain the working temperature in the radome without the need for complex control or coolant routing systems. [0019] The reduced part count and complexity has a number of further advantages such as:- - The radome design and the lack of moving parts makes manufacture and maintenance straightforward; - Reduced likelihood of equipment malfunction due to lack of moving parts, reduced part count and overall improved cooling efficiency; - Weight reduction since no coolant, compression system or coolant pipes are required. This is particularly beneficial in aerospace applications where even a small reduction in weight can result in large gains in overall aircraft performance; - No additional holes need to be provided in the fuselage. This is particularly important in pressurised aircraft where every additional hole through the fuselage results in the potential for a corresponding increase in stress concentration points on the fuselage; - Existing radomes can be replaced with the new radome according to the invention and hence the invention can be easily retrofitted without modification of the existing radar scanner components; and - A minimum change in overall radome profile is required, which is important to maintain the aircraft s aerodynamic characteristics as well as the radome "transparency" to radio waves. [00] Modifications and improvements may be made to the foregoing without departing from the scope of the invention as defined by the claims, for example:- Claims Although in the described embodiment, the invention is installed on an aircraft, it will be appreciated that it could equally be installed over the radar scanner components of any moving craft which is capable of moving at an air speed which results in a sufficient magnitude of ram air being imparted on the air inlet and air outlet. 1. A radome () comprising:- 3

4 EP B1 6 a radar component housing (12); a ram air inlet (18) provided in the radar component housing (12); and a ram air outlet () provided in the radar component housing (12) such that when the radome () is installed on the body of a moving craft, air flow relative to the craft will enter the housing (12) by way of the ram air inlet (18), circulate within the housing (12), and exit the housing (12) by way of the ram air outlet () in order to cool radar components (16) within the radar component housing (12) characterised in that the ram air inlet (18) is provided aft of the ram air outlet () in order to encourage circulation of air within the radar component housing (12). 2. A radome () according to claim 1, wherein the radar components (16) comprise radar scanner components (16). 3. A radome () according to either of claims 1 or 2, wherein the radome () is mountable on an aircraft fuselage (14). 4. A radome () according to any preceding claim, wherein the ram air inlet (18) and ram air outlet () are positioned relative to one another such that a transmission / reception antenna within the radar component housing (12) is cooled by the air circulating within the radar component housing (12).. A radome () according to any preceding claim, wherein the ram air inlet (18) comprises a hole through a wall of the radar component housing (12) and a recessed flap surface in the radar component housing (12). 6. A radome () according to any preceding claim, wherein the ram air inlet (18) is provided in a side wall of the radar component housing (12) A radome () according to claim, wherein the socket comprises a bayonet connection. 12. A radome () according to any preceding claims, wherein a recirculation fan (22) is provided to facilitate circulation of air within the radar component housing (12). 13. A method of cooling radar scanner components, the method comprising the steps of:- housing radar components (16) in a radar component housing (12); providing a ram air inlet (18) in a wall of the radar component housing (12); providing a ram air outlet () in a wall of the radar component housing (12); mounting the radar component housing (12) to a craft; such that, when the craft moves, ram air flows into the air inlet (18), circulates around the radar component housing (12) to cool the radar components (16) within the radar component housing (12), and then exits the radar component housing (12) by way of the ram air outlet () characterised in that the method further comprises the step of encouraging circulation of air within the radar component housing (12) by providing the ram air inlet (18) aft of the ram air outlet (). 14. A method according to claim 13, further comprising the step of providing a socket on the ram air outlet () and connecting the socket to a suction device. 1. A method according to claim 13 or 14, further comprising facilitating circulation of air within the radar component housing (12) by providing a recirculation fan (22). Patentansprüche 7. A radome () according to any preceding claim, wherein a removable filter element is provided at the ram air inlet (18). 8. A radome () according to any preceding claim, wherein the ram air inlet (18) comprises a NACA duct in a wall of the radar component housing (12). 9. A radome () according to any preceding claim, wherein the ram air outlet () is provided in a lower wall of the radar component housing (12).. A radome () according to any preceding claim wherein the ram air outlet () is provided with a socket which allows it to be connected to a suction device Radarkuppel (), umfassend: ein Radarkomponentengehäuse (12); einen Staulufteinlass (18), der in dem Radarkomponentengehäuse (12) bereitgestellt ist; und einen Stauluftauslass (), der in dem Radarkomponentengehäuse (12) derart bereitgestellt ist, dass, wenn die Radarkuppel () auf dem Körper eines sich bewegenden Fahrzeugs installiert ist, ein Luftstrom relativ zu dem Fahrzeug in das Gehäuse (12) durch den Staulufteinlass (18) eintritt, innerhalb des Gehäuses (12) zirkuliert und aus dem Gehäuse (12) durch den Stauluftauslass () austritt, um Radarkomponenten (16) innerhalb des Radarkomponentengehäuses (12) zu kühlen, dadurch gekenn- 4

5 7 EP B1 8 zeichnet, dass der Staulufteinlass (18) achtern von dem Stauluftauslass () bereitgestellt ist, um eine Zirkulation von Luft innerhalb des Radarkomponentengehäuses (12) zu fördern. 2. Radarkuppel () nach Anspruch 1, wobei die Radarkomponenten (16) Radarscannerkomponenten (16) umfassen. 3. Radarkuppel () nach einem der Ansprüche 1 oder 2, wobei die Radarkuppel () an einem Flugzeugrumpf (14) montierbar ist. 4. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei der Staulufteinlass (18) und der Stauluftauslass () relativ zueinander derart positioniert sind, dass eine Sende/Empfangsantenne innerhalb des Radarkomponentengehäuses (12) durch die Luft gekühlt wird, die innerhalb des Radarkomponentengehäuses (12) zirkuliert.. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei der Staulufteinlass (18) ein Loch durch eine Wand des Radarkomponentengehäuses (12) und eine vertiefte Klappenfläche in dem Radarkomponentengehäuse (12) umfasst. 6. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei der Staulufteinlass (18) in einer Seitenwand des Radarkomponentengehäuses (12) bereitgestellt ist. 7. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei ein entfernbares Filterelement an dem Staulufteinlass (18) bereitgestellt ist. 8. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei der Staulufteinlass (18) einen NACA-Kanal in einer Wand des Radarkomponentengehäuses (12) umfasst Verfahren zur Kühlung von Radarscannerkomponenten, wobei das Verfahren die folgenden Schritte umfasst: Unterbringen von Radarkomponenten (16) in einem Radarkomponentengehäuse (12); Bereitstellen eines Staulufteinlasses (18) in einer Wand des Radarkomponentengehäuses (12); Bereitstellen eines Stauluftauslasses () in einer Wand des Radarkomponentengehäuses (12); Montieren des Radarkomponentengehäuses (12) an einem Fahrzeug derart, dass, wenn sich das Fahrzeug bewegt, Stauluft in den Lufteinlass (18) strömt, in dem Radarkomponentengehäuse (12) herum zirkuliert, um die Radarkomponenten (16) innerhalb des Radarkomponentengehäuses (12) zu kühlen, und dann aus dem Radarkomponentengehäuse (12) durch den Stauluftauslass () austritt, dadurch gekennzeichnet, dass das Verfahren ferner den Schritt des Förderns einer Zirkulation von Luft innerhalb des Radarkomponentengehäuses (12) umfasst, indem der Staulufteinlass (18) achtern von dem Stauluftauslass () bereitgestellt wird. 14. Verfahren nach Anspruch 13, ferner umfassend den Schritt des Bereitstellens einer Buchse an dem Stauluftauslass () und des Verbindens der Buchse mit einer Saugvorrichtung. 1. Verfahren nach Anspruch 13 oder 14, ferner umfassend das Erleichtern einer Zirkulation von Luft innerhalb des Radarkomponentengehäuses (12), indem ein Umluftgebläse (22) bereitgestellt wird. Revendications 9. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei der Stauluftauslass () in einer unteren Wand des Radarkomponentengehäuses (12) bereitgestellt ist.. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei der Stauluftauslass () mit einer Buchse versehen ist, die es diesem ermöglicht, mit einer Saugvorrichtung verbunden zu werden. 11. Radarkuppel () nach Anspruch, wobei die Buchse einen Bajonettanschluss umfasst. 12. Radarkuppel () nach einem der vorhergehenden Ansprüche, wobei ein Umluftgebläse (22) bereitgestellt ist, um eine Zirkulation von Luft innerhalb des Radarkomponentengehäuses (12) zu erleichtern Radôme () comprenant : un logement de composants de radar (12) ; une entrée d air dynamique (18) fournie dans le logement de composants de radar (12) ; et une sortie d air dynamique () fournie dans le logement de composants de radar (12) de sorte que lorsque le radôme () est installé sur le corps d un appareil mobile, un flux d air par rapport à l appareil va entrer dans le logement (12) via l entrée d air dynamique (18), circuler à l intérieur du logement (12), et sortir du logement (12) via la sortie d air dynamique () afin de refroidir les composants de radar (16) à l intérieur du logement de composants de radar (12), caractérisé en ce que l entrée d air dynamique (18) est fournie à l arrière de la sortie d air dy-

6 9 EP B1 namique () afin de favoriser une circulation d air à l intérieur du logement de composants de radar (12). recirculation (22) est fourni pour faciliter une circulation d air à l intérieur du logement de composants de radar (12). 2. Radôme () selon la revendication 1, dans lequel les composants de radar (16) comprennent des composants de scanner radar (16). 3. Radôme () selon l une quelconque des revendications 1 ou 2, dans lequel le radôme () peut être monté sur un fuselage d avion (14). 4. Radôme () selon l une quelconque des revendications (18) et la sortie d air dynamique () sont positionnées l une par rapport à l autre de façon à ce qu une antenne de transmission/réception à l intérieur du logement de composants de radar (12) soit refroidie par l air circulant à l intérieur du logement de composants de radar (12).. Radôme () selon l une quelconque des revendications (18) comprend un trou à travers une paroi du logement de composants de radar (12) et une surface de volet évidée dans le logement de composants de radar (12). 6. Radôme () selon l une quelconque des revendications (18) est fournie dans une paroi latérale du logement de composants de radar (12). 7. Radôme () selon l une quelconque des revendications précédentes, dans lequel un élément de filtre amovible est fourni au niveau de l entrée d air dynamique (18). 8. Radôme () selon l une quelconque des revendications (18) comprend un conduit NACA dans une paroi du logement de composants de radar (12) Procédé pour refroidir des composants de scanner radar, le procédé comprenant les étapes de : logement de composants de radar (16) dans un logement de composants de radar (12) ; fourniture d une entrée d air dynamique (18) dans une paroi du logement de composants de radar (12) ; fourniture d une sortie d air dynamique () dans une paroi du logement de composants de radar (12) ; montage du logement de composant de radar (12) sur un appareil ; de sorte que, lorsque l appareil se déplace, de l air dynamique s écoule dans l entrée d air (18), circule autour du logement de composants de radar (12) pour refroidir les composants de radar (16) à l intérieur du logement de composants de radar (12), et ensuite sort du logement de composants de radar (12) via la sortie d air dynamique (), caractérisé en ce que le procédé comprend en outre l étape consistant à favoriser une circulation d air à l intérieur du logement de composants de radar (12) par la fourniture de l entrée d air dynamique (18) à l arrière de la sortie d air dynamique (). 14. Procédé selon la revendication 13, comprenant en outre l étape de fourniture d un raccord sur la sortie d air dynamique () et de connexion du raccord à un dispositif d aspiration. 1. Procédé selon la revendication 13 ou 14, comprenant en outre la facilitation d une circulation d air à l intérieur du logement de composants de radar (12) par la fourniture d un ventilateur de recirculation (22). 9. Radôme () selon l une quelconque des revendications précédentes, dans lequel la sortie d air dynamique () est fournie dans une paroi inférieure du logement de composants de radar (12). 4. Radôme () selon l une quelconque des revendications précédentes, dans lequel la sortie d air dynamique () est dotée d un raccord qui lui permet d être relié à un dispositif d aspiration Radôme () selon la revendication, dans lequel le raccord comprend une liaison à baïonnette. 12. Radôme () selon l une quelconque des revendications précédentes, dans lequel un ventilateur de 6

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