EP3022800B1 - Assembly and method for installing a direction-finding antenna in a radome, preferably for retrofitting a direction-finding antenna in a radome - Google Patents

Description

The invention relates to an arrangement and a method for installing a DF antenna in a radome, preferably for retrofitting into a radome.

Locations that are undisturbed and free from reflectors are generally best suited for the installation of DF antennas, so as not to influence the DF accuracy as far as possible. Especially in mobile locations, such as mobile units, e.g. Vehicles and ships, a DF antenna mounting on the highest point of the mobile unit, e.g. of the vehicle or the ship, sought. However, modern mobile units usually have a large number of different antennas, not just DF antennas, and sensors, some of which also claim the best possible location location on the vehicle and / or carrier tip.

DF antennas have to operate in a very wide frequency range today, for example, a VHF / UHF DF antenna must cover a frequency range of at least 20 MHz to 3 GHz. In general, such frequency ranges can not be realized with sufficient efficiency with only one DF antenna system and these DF antennas must generally consist of several subsystems. The DF antenna subsystems for the upper frequency ranges usually have small dimensions and can be accommodated on a mobile unit, eg on a vehicle and / or a ship, usually without problems or major difficulties. DF subsystem for lower frequencies have due to the correspondingly large wavelength, for example, from 20 MHz about 15 m, correspondingly larger dimensions. In general, for deeper frequencies, it is desirable to have dipoles with a correspondingly large effective height. For mobile applications DF antennas are often built in a compact design, the DF antenna subsystems for the upper frequency ranges to the antenna center usually have smaller dimensions and can be realized with sufficient efficiency. The dimensions of the antenna subsystem for the lower frequency ranges are available in antennas in a compact design by the given available Overall antenna height determined so that a sufficient or desired efficiency can not be optimally realized and in the compact design inevitably a compromise between the dimensions in particular the antenna height and the antenna sensitivity thus achievable must be concluded.

Bearing systems with dimensions which are optimal in terms of sensitivity have dipoles in the order of less than one meter to several meters, preferably from 0.8 to 1.8 meters, particularly preferably one meter, for the lower frequency ranges and can be mounted on mobile units, for example Vehicles and / or ships, not easily attach. Optimally, the DF antenna subsystem with the largest dimensions for the low frequency range should be on the carrier tip. This achieves optimal antenna sensitivity. Such an arrangement with correspondingly complex, special construction is usually possible only with special vehicles. Modern mobile systems such as vehicles and / or ships do not allow this construction due to space limitations.

By doing Manual "Funkpeiltechnik" by Rudolf Grabau and Klaus Pfaff, Franckh'sche Verlagshandlung, W. Keller & Co., Stuttgart 1989, page 411 is shown a DF antenna with multiple direction finding systems ,

The DE 101 03 965 C2 relates to a single or multiple antenna pointing system, for example according to the Adcock method for use preferably in mobile systems under severe mechanical and climatic stress, wherein an antenna construction comprises a plurality of antenna radiators.

The invention has for its object an arrangement and a method for installing a DF antenna in a radome, preferably for retrofitting into a radome to provide.

This object is achieved with one of the methods and a device according to the independent patent claims.

The dependent claims relate to further aspects of the invention.

The invention is based on the basic idea of providing an arrangement for, preferably retrofitting, Peilantenneneinbau in a radome of an existing satellite and / or sensor system on a vehicle and / or a ship, in which the retrofitted antenna elements, such as dipoles, be subsequently attached to the inner wall of the radome. The number of antenna elements depends on the selected DF method. The retrofitted antenna elements or dipoles can be subsequently glued into the radome of metallic self-adhesive film.

The invention relates to an arrangement for installing a DF antenna in a radome, preferably for retrofitting in a radome, comprising: at least one antenna element which is mounted on the inside of an outer shell of the radome, and wherein the DF antenna is preferably for use in an interferometer and or in an adcock-bearing method, particularly preferably in a correlative interferometer-pointing method.

Furthermore, the DF antenna may be particularly suitable for use in mobile systems, wherein the mobile systems are suitable for carrying out at least one of said DF methods.

A radome can have a radome and / or a closed or at least partially closed protective sleeve enclosing antennas for measurements and / or data transmissions, for example direction finding antennas. A radome can have a bottom plate. This bottom plate can be arranged parallel to the ground or at an angle to the ground.

A radome can have a circular base. Furthermore, the radome may have a spherical or cylindrical outer shell provided with a spherical dome. Furthermore, the outer shell may be in the shape of an icosahedron, an icosahedral stump, a dodecahedron, or any other polyhedron.

The outer shell of the radome may comprise a flexible material and / or a rigid material. The outer shell of the radome may in particular be suitable for protecting the antennas enclosed by the outer shell of the radome from external mechanical and / or chemical influences, for example wind, rain or seawater.

A mobile system may be a land vehicle, an aircraft, and / or preferably a ship.

The antenna elements may be arranged on the entire Radomfläche. In one embodiment, the at least one antenna element may be mounted in the lower half of the inside of the outer shell of the radome and / or in the upper half of the inside of the outer shell of the radome.

According to a further embodiment, the arrangement comprises a plurality of antenna elements, preferably 7 antenna elements, wherein the plurality of antenna elements are preferably mounted equidistantly on the inside of an outer shell of the radome. In particular, equidistant may mean that the plurality of antenna elements are equidistant from each other along the circumference of the radome. For example, in the embodiment with 7 antenna elements, each antenna element "n" is located at a position n * 360 ° / 7, where n = 1,2,3, ..., 7. In particular, in an embodiment with "m" antenna elements, for example, each antenna element "n" may be arranged at a position n · 360 ° / m, where n = 1, ..., m. The arrangements 4, 5, 7, 8, or 9 can particularly preferably have antenna elements.

In a further embodiment, the at least one antenna element has a dipole antenna or the multiple antenna elements each have a dipole antenna, wherein the dipole antenna or the respective dipole antenna has a long and a short extension direction and wherein the long extension direction of the dipole antenna or the respective dipole antenna is preferably aligned perpendicular to the circumferential direction of the radome.

A dipole antenna can be a broadband dipole antenna, preferably suitable for large frequency ranges.

According to a further embodiment, the at least one antenna element is glued to the inside of the outer shell of the radome. The at least one antenna element can also have a self-adhesive, metallic foil and / or have at least one flexible printed circuit board. The at least one antenna element can also be metallically deposited on the inside of the outer shell of the radome.

The self-adhesive metallic foil may comprise aluminum and / or copper. The at least one antenna element can also be metallically deposited on the inside of the outer shell of the radome made of aluminum, copper and / or silver. Furthermore, at least one insulation and / or protective layer can be vapor-deposited and / or applied.

In a further embodiment of the arrangement, the antenna element (s) form a DF antenna subsystem, and the DF antenna subsystem can be combined with at least one further subsystem, wherein the arrangement particularly preferably has at least one feed line for forwarding antenna signals from the at least one antenna element to at least one antenna electronics.

An antenna electronics may have a matching amplifier and / or an amplifier and / or switching elements.

A feed line may be suitable for looping antenna signals from the at least one antenna element to at least one element of the antenna electronics. Such a feed line may be an insulated copper line, for example a coaxial cable, or a fiber optic cable.

Also, a feeder may be made up of multiple copper or fiber optic cables or a combination of copper and fiber optic cables.

According to a further embodiment, the at least one feed line is subdivided into a first part with the length S1 and a second part with the length S2, wherein the feed line is connected to one end of the first part with the at least one antenna element, the first part substantially is aligned parallel to the circumferential direction of the radome and / or wherein the second part is oriented substantially perpendicular to the circumferential direction in the direction of a bottom plate of the radome. The lengths S1 and S2 can be the same or different. The two parts of the feed line can be clearly separated from each other and / or be configured in two parts. The two parts of the feed line can also be designed in one piece and / or designed indistinguishable.

In a further embodiment, the arrangement has at least one first and one second antenna element and at least one first and one second feed line. In this case, the first feed line is divided into a first part with the length S1 and a second part with the length S2 and the second feed line is divided into a first part with the length S1 'and a second part with the length S2'. The first feed line is connected to one end of the associated first part with the first antenna element and the second feed line is connected to one end of the associated first part to the second antenna element. The first parts of the first and second feeders are aligned substantially parallel to the circumferential direction of the radome and / or the second parts of the first and second feeders are adjacent and oriented substantially perpendicular to the circumferential direction in the direction of a bottom plate of the radome. The number of antenna elements is preferably greater than the number of elements of the at least one antenna electronics. The lengths S 1 and S2 may be the same or different. Also, the lengths S 1 and S1 'or S2 and S2' may be the same or different.

According to a further embodiment, the number of the at least one antenna element is selected depending on the bearing method to be used.

Thus, in an Adcock or an Adcock / Watson Watt direction finding method, preferably 4 or 8 antenna elements can be attached. In an interferometer DF method and / or a correlative interferometer direction finding preferably 5 or 9 antenna elements, particularly preferably in a correlative interferometer DF method 7 antenna elements, are attached.

According to the invention, a radome is provided with a DF antenna as described above.

In a further embodiment, an interior of the radome has at least one further device for locating and / or receiving and / or transmitting radio signals, preferably satellite signals, and / or at least one sensor system.

A sensor system may include a radar antenna. An apparatus for receiving and transmitting radio signals may comprise an antenna for satellite navigation.

The invention also relates to a method for installing a DF antenna in a radome, preferably for retrofitting into a radome, comprising the following step: attaching at least one antenna element to the inside of an outer shell of the radome, the DF antenna preferably for use in an interferometer, a correlative interferometer and / or in an Adcock direction finding method, wherein the DF antenna is preferably for use in an interferometer and / or in an adcock bearing method, more preferably in a correlative interferometer and further particularly preferably for use in mobile systems suitable for performing at least one of Bearing method is suitable.

The antenna elements may be arranged on the entire Radomfläche. According to one embodiment, the at least one antenna element is mounted in the lower half of the inside of the outer shell of the radome and / or in the upper half of the inside of the outer shell of the radome.

In a further embodiment, in the method a plurality of antenna elements are mounted, preferably 7 antenna elements, wherein the plurality of antenna elements preferably be equidistantly mounted on the inside of an outer shell of the radome.

According to a further embodiment, in the method, the at least one antenna element on a dipole antenna or the plurality of antenna elements each have a dipole antenna, wherein the dipole antenna or the respective dipole antenna has a long and a short extension direction and wherein the long extension direction of the dipole antenna or the respective dipole antenna is preferably aligned perpendicular to the circumferential direction of the radome.

In a further embodiment, the method has the following further steps: adhesion of the at least one antenna element to the inside of the outer shell of the radome and / or metallic vapor deposition of the at least one antenna element to the inside of the outer shell of the radome.

According to a further embodiment, the method has the fastening, preferably sticking, of the at least one antenna element as a self-adhesive metallic foil and / or of the at least one antenna element in the form of at least one flexible printed circuit board.

• Bilden eines Peilantennen-Teilsystems aus Antennenelementen, und vorzugsweise Kombinieren des Peilantennen-Teilsystem mit mindestens einem weiteren Teilsystem, vorzugsweise mit dem weiteren Schritt:
  • Verbinden mindestens einer Speiseleitung mit dem mindestens einen Antennenelement und mindestens einer Antennenelektronik, wobei die mindestens eine Speiseleitung zum Weiterleiten von Antennensignalen von dem mindestens einen Antennenelement zu der mindestens einen Antennenelektronik geeignet ist.

In a further embodiment, the method comprises the further steps:

• Forming a DF antenna subsystem of antenna elements, and preferably combining the DF antenna subsystem with at least one further subsystem, preferably with the further step:
  • Connecting at least one feed line to the at least one antenna element and at least one antenna electronics, wherein the at least one feed line for forwarding antenna signals from the at least one antenna element to the at least one antenna electronics is suitable.

According to a further embodiment, in the method, the at least one feed line is divided into a first part with the length S 1 and a second part with the length S2, wherein the feed line with one end of the first part with the at least an antenna element is connected, wherein the first part is aligned substantially parallel to the circumferential direction of the radome and / or wherein the second part is oriented substantially perpendicular to the circumferential direction in the direction of a bottom plate of the radome.

In a further embodiment, in the method at least a first and a second antenna element are attached and connected to at least a first and a second feed line,
wherein the first feed line is divided into a first part of length S1 and a second part of length S2, and the second feed line is divided into a first part of length S1 'and a second part of length S2',
wherein the first feed line is connected to one end of the associated first part to the first antenna element and the second feed line is connected to one end of the associated first part to the second antenna element, and wherein the first parts of the first and second feed lines are substantially parallel to the circumferential direction the radome are aligned and / or
wherein the second parts of the first and second feeders are adjacent and aligned substantially perpendicular to the circumferential direction towards a bottom plate of the radome, and
wherein preferably the number of antenna elements is greater than the number of elements of the at least one antenna electronics.

According to a further embodiment, in the method, the number of the at least one antenna element to be attached is selected depending on the direction finding method to be used.

In a further embodiment, in the method, the radome has at least one further device for locating and / or receiving and / or transmitting radio signals, preferably satellite signals, and / or at least one sensor system.

• Figur 1 eine schematische Zeichnung einer Anordnung zum Einbau einer Peilantenne in ein Radom gemäß einer Ausführungsform der Erfindung, und
• Figur 2 eine schematische Zeichnung einer Anordnung zum Einbau einer Peilantenne in ein Radom gemäß einer weiteren Ausführungsform der Erfindung.

It shows:

• FIG. 1 a schematic drawing of an arrangement for installation of a DF antenna in a radome according to an embodiment of the invention, and
• FIG. 2 a schematic drawing of an arrangement for installation of a DF antenna in a radome according to another embodiment of the invention.

FIG. 1 shows a schematic drawing of an arrangement for installation of a DF antenna in a radome according to an embodiment of the invention.

To the inside of the outer shell of the radome 300 a plurality of antenna elements 101 of the arrangement along the Radomumfangs are glued equidistant. The multiple antenna elements 101 are each configured as dipole antennas and each have a short and a long extension direction. The long extension directions of the dipole antennas are aligned parallel to each other and perpendicular to the circumferential direction of the radome 300 and the bottom plate or bottom frame 500 of the radome 300, respectively.

The antenna elements 101 embodied as dipole antennas are connected in each case via a connecting element 103 to feed lines 102, wherein the feed line 102 is subdivided into a first part with a length S 1 and a second part with the length S 2. The first part is the part connected to the antenna element 101. The first part is aligned substantially parallel to the circumferential direction of the radome 300 and thus aligned according to the present embodiment perpendicular to the long extension direction of the antenna element 101. The second part of the feed line 102 with the length S2 is oriented substantially perpendicular to the circumferential direction and thus according to the present embodiment parallel to the antenna element 101. The second part with the length S2 of the feed line 102 points in the direction of the bottom plate of the radome.

The second part of the feed line 102 is further connected to an element 201 of an antenna electronics. The antenna electronics can be used for further processing and / or forwarding the direction finding signals received by the antenna element 101 be suitable. The antenna electronics elements 201 are mounted on the floorstand 500 according to the present embodiment.

In the radome 300 is also a parabolic antenna 400, which is suitable for satellite communication.

FIG. 2 shows a schematic drawing of an arrangement for installation of a DF antenna in a radome 300 according to another embodiment of the invention. As in the first, in FIG. 1 In the embodiment shown, in the radome is a satellite antenna 400 for satellite communication.

In this embodiment, also antenna elements 101 and 101 'of an arrangement for mounting a DF antenna in a radome along the Radomumfangs are adhered to the inside of the outer shell of the radome 300. The antenna elements 101 and 101 'are also formed as dipole antennas in this embodiment, and the long extension directions of the antenna elements 101 and 101' are aligned parallel to each other and perpendicular to the bottom plate and the bottom frame 500 and perpendicular to the circumferential direction of the radome 300. The antenna element 101 is connected to a feed line 102 via a connecting element 103 and the antenna element 101 'is connected to the feed line 102' via a connecting element 103 '. The feed line 102 is divided into a first part with the length S 1 and a second part with the length S2. The second feed line 102 'is divided into a first part with the length S1' and a second part with the length S2 '. In this case, the first feed line 102 is connected to one end of the associated first part via the connecting element 103 to the first antenna element 101 'and the second feed line 102' is connected to one end of the associated first part to the second antenna element 101 '. The first parts of the first and second feeders 102 and 102 'are aligned parallel to the circumferential direction and parallel to the bottom plate or base 500. Unlike in FIG. 1 In the embodiment shown, the second parts with the length S2 or S2 'are adjacent to the first and second feed lines 102 and 102', ie preferably at a distance of a few millimeters to a few centimeters. Also, the second parts of length S2 and S2 'are the first and second Feed line 102 and 102 'perpendicular to the circumferential direction and thus aligned parallel to the long extension direction of the antenna elements 101 and 101'. The second parts of the first and second supply lines 102 and 102 'are connected to a common element 201 of an antenna electronics. Therefore, this embodiment is particularly suitable if fewer elements 201 of the antenna electronics than antenna elements 101 and 101 'are available.

Although the invention has been described and illustrated in detail by the invention and the accompanying description, these drawings and this detailed description are to be considered as illustrative and exemplary and not as limiting the invention. It is understood that professionals can make changes without departing from the scope and spirit of the following claims. In particular, the invention also includes embodiments with a combination of features, which are mentioned or shown above or below different embodiments.

The invention also includes individual features in the figures, even though they are shown there in connection with other features and / or are not mentioned above or below. Also, the alternatives of embodiments and individual alternatives of the features described in the figures and the description may be excluded from the subject matter of the invention or from the disclosed subject matter. The disclosure includes embodiments that include only the features described in the claims and in the embodiments, as well as those that additionally include other features.

Claims (21)

1. An assembly for subsequently installing a direction-finding antenna in a radome (300), comprising:

   a radome (300) and a plurality of antenna elements (101, 101') which are attached to the inside of an outer shell of the radome (300), wherein the plurality of antenna elements (101, 101') comprise a dipole antenna each, wherein the respective dipole antenna has a long and a short extension direction and wherein said long extension direction of the respective dipole antenna is preferably vertically alignable to the circumferential direction of the radome (300), and

   wherein the direction-finding antenna is suitable for use in an interferometer direction-finding method and/or in an Adcock direction-finding method, preferably in a correlative interferometer direction-finding method and particularly preferably for use in mobile systems suitable for performing at least one of the mentioned direction-finding methods.
2. The assembly according to claim 1, wherein the plurality of antenna elements (101, 101') are mounted in the lower half of the inside of the outer shell of the radome (300) and/or in the upper half of the inside of the outer shell of the radome (300).
3. The assembly according to claim 1 or 2, wherein the plurality of antenna elements (101, 101') are equidistantly mounted to the inside of an outer shell of the radome (300).
4. The assembly according to any one of claims 1 to 3, comprising 7 antenna elements (101, 101').
5. The assembly according to any one of claims 1 to 4, wherein the plurality of antenna elements (101, 101') are adhered to the inside of the outer shell of the radome (300) and/or comprise a self-adhesive metallic foil and/or at least one flexible printed circuit board and/or are applied to the inside of the outer shell of the radome (300) by metallic vapor deposition.
6. The assembly according to any one of claims 1 to 5, wherein the plurality of antenna elements (101, 101') form a direction-finding antenna subsystem and the direction-finding antenna subsystem can be combined with at least one further subsystem, wherein the assembly comprises at least one feeder line (102, 102') for routing antenna signals from the plurality of antenna elements (101, 101') to at least one antenna electronics (201).
7. The assembly according to claim 6, wherein the at least one feeder line (102, 102') is divided into a first part having a length S1 and a second part having a length S2, wherein the feeder line is connected with one end of the first part to the at least one antenna element (101, 101'), wherein the first part is aligned substantially in parallel to the circumferential direction of the radome (300) and/or wherein the second part is aligned substantially vertically to the circumferential direction towards a baseplate (500) of the radome (300).
8. The assembly according to claim 6, comprising at least a first and a second antenna element (101, 101') and at least a first and a second feeder line (102, 102'),
   wherein the first feeder line (102) is divided into a first part having a length S1 and a second part having a length S2, and the second feeder line (102') is divided into a first part having a length S1' and a second part having a length S2',
   wherein the first feeder line (102) is connected with one end of the respective first part to the first antenna element (101), and the second feeder line (102') is connected with one end of the respective first part to the second antenna element (101'), and
   wherein the first parts of the first and second feeder lines (102, 102') are aligned substantially in parallel to the circumferential direction of the radome(300)
   and/or
   wherein the second parts of the first and second feeder lines (102, 102') are adjacent to each other and are aligned substantially vertically to the circumferential direction towards a baseplate (500) of the radome (300), and
   wherein preferably the number of antenna elements (101, 101') is larger than the number of elements of the at least one antenna electronics (201).
9. The assembly according to any one of claims 1 to 8, wherein the number of the plurality of antenna elements (101, 101') is selected depending on the direction-finding method to be used.
10. The assembly according to any one of claims 1 to 9, wherein an interior of the radome (300) comprises at least one further device (400) for the direction finding and/or receiving and/or transmitting of radio signals, preferably satellite signals, and/or at least one sensor system.
11. A method for subsequently installing a direction-finding antenna in a radome (300), comprising the following step:

    mounting a plurality of antenna elements (101, 101') to the inside of an outer shell of the radome (300),

    wherein the plurality of antenna elements (101, 101') comprise a dipole antenna each, wherein the respective dipole antenna has a long and a short extension direction and wherein said long extension direction of the respective dipole antenna is preferably vertically alignable to the circumferential direction of the radome (300), and

    wherein the direction-finding antenna is suitable for use in an interferometer direction-finding method, a correlative interferometer direction-finding method and/or in an Adcock direction-finding method, wherein the direction-finding antenna is preferably suitable for use in a correlative interferometer direction-finding method, and further particularly preferably for use in mobile systems suitable for performing at least one of said direction-finding methods.
12. The method of claim 11, wherein the plurality of antenna elements (101, 101') are mounted in the lower half of the inside of the outer shell of the radome (300) and/or in the upper half of the inside of the outer shell of the radome (300).
13. The method according to claim 11 or 12, wherein a plurality of antenna elements (101, 101') equidistantly mounted on the inside of an outer shell of the radome (300).
14. The method according to any one of claims 11 to 13, wherein 7 antenna elements (101, 101') are mounted.
15. The method according to any one of claims 11 to 14, comprising the steps of: adhering the plurality of antenna elements (101, 101') to the inside of the outer shell of the radome (300) and/or applying the plurality of antenna elements (101, 101') to the inside of the outer shell of the radome (300) by metallic vapor deposition.
16. The method according to any one of claims 11 to 15, comprising the further steps of:

    fastening the plurality of antenna elements (101, 101') as self-adhesive metallic foil and/or fastening the plurality of antenna elements (101, 101') in the form of a flexible printed circuit board.
17. The method according to any one of claims 11 to 16, comprising the further steps of:

    forming a direction-finding antenna subsystem from antenna elements (101, 101'), and preferably combining the direction-finding antenna subsystem with at least one further subsystem, comprising the further step of:

    connecting at least one feeder line (102, 102') to the at one of the antenna elements (101, 101') and to at least one antenna electronics (201), wherein the at least one feeder line (102, 102') is suitable for routing antenna signals from the antenna element (101, 101') to the at least one antenna electronics (201).
18. The method of claim 17, wherein the at least one feeder line (102, 102') is divided into a first part having a length S1 and a second part having a length S2, wherein the feeder line (102, 102') is connected with one end of the first part to the at least one antenna element (101, 101'), wherein the first part is aligned substantially in parallel to the circumferential direction of the radome (300) and/or wherein the second part is aligned substantially vertically to the circumferential direction towards a baseplate (400) of the radome (300).
19. The method of claim 17, wherein at least a first and a second antenna element (101, 101') are mounted and connected to at least a first and a second feeder line (102, 102'),
    wherein the first feeder line (102) is divided into a first part having a length S1 and a second part having a length S2, and the second feeder line (102') is divided into a first part having a length S1' and a second part having a length S2',
    wherein the first feeder line (102) is connected with one end of the respective first part to the first antenna element (201), and the second feeder line (102') is connected with one end of the respective first part to the second antenna element (101'), and
    wherein the first parts of the first and second feeder lines (102, 102') are aligned substantially in parallel to the circumferential direction of the radome (300) and/or wherein the second parts of the first and second feeder lines (102, 102') are adjacent to each other and are aligned substantially vertically to the circumferential direction towards a baseplate (500) of the radome (300), and
    wherein preferably the number of antenna elements (101, 101') is larger than the number of elements of the at least one antenna electronics (201).
20. The method according to any one of claims 11 to 19, wherein the number of the plurality of antenna elements to be mounted is selected depending on the direction-finding method to be used.
21. The method according to any one of claims 11 to 20, wherein the radome (300) comprises at least one further device (400) for the direction finding and/or receiving and/or transmitting of radio signals, preferably satellite signals, and/or at least a sensor system.

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