Abstract
A reflector for a multi-radiator antenna which comprises electrically conducting reflector parts and one or more connector device. At least two reflector parts are each provided with at least one connecting portion. At least one connector device is adapted to provide an electrical interconnection between at least two of the reflector parts. At least one connector device comprises a metallic film and one or more holding elements. The metallic film is adapted to be arranged in abutment with connecting portions of the at least two of the reflector parts to achieve the electrical interconnection. At least one of the holding elements has at least one holding portion adapted to connect to a connecting portion of a reflector part with said metallic film sandwiched therebetween. The electrical interconnection is indirect by means of a dielectric coating or layer arranged on the metallic film and/or on the connecting portions, or by means of a dielectric film arranged between the metallic film and the connecting portions.
Claims
1. A reflector for a multi-radiator antenna, said reflector comprising: at least two electrically conducting reflector parts, each having at least one connecting portion; at least one connector device adapted to provide an electrical interconnection between at least two of the reflector parts, each connector device comprising a metallic film adapted to be arranged in abutment with connecting portions of said at least two of the reflector parts to achieve said electrical interconnection, and one or more holding elements, wherein at least one of the holding elements has at least one holding portion adapted to connect to a connecting portion of a reflector part with said metallic film sandwiched therebetween, wherein the electrical interconnection is indirect by means of a dielectric coating or layer arranged on the metallic film and/or on the connecting portions, or by means of a dielectric film arranged between the metallic film and the connecting portions.
2. The reflector according to claim 1, wherein said dielectric coating or layer is arranged on the metallic film on at least the side thereof facing the connecting portions.
3. The reflector according to claim 1, wherein at least one holding element is at least partly made from a resilient material to force the metallic film against the connecting portions of said at least two of the reflector parts.
4. The reflector according to claim 1, wherein at least the holding portions of at least one holding element are resilient to force the metallic film against the connecting portions of said at least two of the reflector parts.
5. The reflector according to claim 1, wherein the holding element comprises at least one spring portion adapted to force the at least one holding portion towards said connecting portion.
6. The reflector according to claim 1, wherein at least one holding portion of the at least one holding element is configured to connect with a corresponding connecting portion of a reflector part by means of abutting contact therewith.
7. The reflector according to claim 1, wherein at least one holding portion of the at least one holding element is configured to connect with a corresponding connecting portion of a reflector part by engaging around at least parts of said connecting portion.
8. The reflector according to claim 1, wherein at least one holding element or at least one holding portion of the at least one holding element is resiliently compressible and is configured to connect with a corresponding connecting portion of a reflector part by means of said connecting portion being formed as a cavity into which said holding portion is releasably insertable.
9. The reflector according to claim 1, comprising first and second reflector parts wherein the first reflector part comprises a first connecting portion formed as a protrusion, and wherein the second reflector part comprises a second connecting portion formed as a cavity adapted to receive said first connecting portion and a connector device to electrically interconnect said first and second reflector parts, said connector device having a holding element being at least partly resiliently compressible and being adapted to connect to the first and second connecting portions with said metallic film or said metallic film and said dielectric film sandwiched therebetween.
10. The reflector according to claim 1, wherein at least one connector device comprises at least one holding element having at least two holding portions, and wherein the metallic film extends between the holding portions by at least partly surrounding the periphery of the holding element.
11. The reflector according to claim 1, wherein at least one connector device is adapted to interconnect said at least two of the reflector parts capacitively.
12. The reflector according to claim 1, wherein at least one connector device extends along essentially the whole length of the reflector parts when connected thereto.
13. The reflector according to claim 1, wherein at least one connector device comprises at least two holding elements adapted to be arranged consecutively along the length of the reflector parts to connect to a connecting portion of a reflector part with said metallic film sandwiched therebetween.
14. The reflector 3according to claim 1, wherein at least two connector devices are arranged consecutively along the length of the reflector parts when connected thereto.
15. The reflector according to claim 1, wherein said at least one holding element is non-conductive.
16. The reflector according to claim 1, wherein said reflector comprises at least two parallel reflector portions to form a reflector for a multi-array antenna arrangement having at least two arrays of antenna elements, wherein at least one reflector portion is formed by at least two reflector parts.
17. A multi-array antenna arrangement comprising a reflector according to claim 1, wherein at least two of the reflector parts are each provided with an antenna feeding network module and at least two antenna elements arranged on the reflector part and being electrically connected to said antenna feeding network module.
18. The multi-array antenna arrangement according to claim 17, wherein said antenna feeding network module comprises at least two transmission lines being coaxial lines having at least one inner conductor being at least partly surrounded by an elongated outer conductor with air therebetween.
19. The multi-array antenna arrangement according to claim 17, wherein said antenna feeding network module comprises at least two transmission lines having at least one flat conductor placed between two ground planes or essentially interacting only with one ground plane.
20. The multi-array antenna arrangement according to claim 17, wherein said antenna feeding network module comprises at least two transmission lines being bendable coaxial cables using for instance PTFE or PE as dielectric.
21. The multi-array antenna arrangement according to claim 18, wherein at least one antenna feeding network module is arranged substantially perpendicular to the corresponding reflector part.
22. The multi-array antenna arrangement according to claim 17, wherein at least one reflector part along with the corresponding antenna feeding network module and antenna elements forms a multi-radiator antenna having its reflector formed partly by said reflector part and partly by one or more adjacent reflector parts.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0054] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
[0055] Above discussed and other aspects of the present invention will now be described in more detail using the appended drawings, which show presently preferred embodiments of the invention, wherein:
[0056] FIG. 1 is a schematic illustration of a prior art multi-band antenna comprising a reflector formed as a single extruded aluminium profile,
[0057] FIG. 2 is a schematic illustration of an embodiment of a reflector according to the first or fourth aspect of the invention,
[0058] FIG. 3 is a schematic illustration of an embodiment of a multi-array antenna arrangement according to the second or fifth aspect of the invention, which comprises the reflector shown in FIG. 2,
[0059] FIG. 4 is a schematic illustration of the multi-array antenna arrangement in FIG. 3, further provided with mechanical connectors,
[0060] FIG. 5 is a detail view of the interconnection between the second and third reflector part in FIGS. 1-3,
[0061] FIG. 6 shows a cross section view of parts of an embodiment of a reflector according to the first or fourth aspect of the invention,
[0062] FIG. 7 shows a perspective view of the same embodiment as in FIG. 6,
[0063] FIG. 8 shows a cross section view of parts of another embodiment of a reflector according to the first or fourth aspect of the invention,
[0064] FIG. 9 shows a cross section view of parts of yet another embodiment of a reflector according to the first or fourth aspect of the invention,
[0065] FIG. 10 shows a perspective view of the same embodiment as in FIG. 9,
[0066] FIG. 11 is a schematic illustration of an alternative embodiment of a multi-array antenna arrangement according to the second or fifth aspect of the invention, which comprises the reflector shown in FIG. 2, and
[0067] FIG. 12 is a schematic illustration of yet another embodiment of a multi-array antenna arrangement according to the second or fifth aspect of the invention, which comprises the reflector shown in FIG. 2.
DETAILED DESCRIPTION
[0068] FIG. 1 is a schematic cross section illustration of a prior art multi-band antenna comprising a reflector formed as a single extruded aluminium profile. The antenna comprises a reflector 101 formed integrally with the antenna feeding networks 108a-c as an extruded aluminium profile. Each antenna feeding network comprises a number of coaxial lines, each formed by a central inner conductor surrounded by an outer conductor formed by a compartment in the aluminium profile with air between the inner and outer conductors. Three arrays of antenna elements 107a, 107b, 107c (only one antenna element of each array can be seen in the shown cross section) are arranged consecutively in the lengthwise direction of the antenna on the reflector 101 to form one Low Band (LB) multi-radiator antenna (antenna elements 107b) and two High Band (HB) multi-radiator antennas (antenna elements 107a, 107c). The arrays of antenna elements 107a-c are electrically connected to a corresponding feeding network 108a-c.
[0069] FIG. 2 is a schematic cross section illustration of an embodiment of a reflector 1 according to the first or fourth aspect of the invention. In this embodiment, the reflector comprises electrically conducting reflector parts 2a-2i and connector devices 3a-3h which electrically interconnect the reflector parts in an indirect (capacitive) manner to form the reflector 1. Reflector part 2a is provided with connecting portion 2a′ in the form of a cavity in which a protruding connecting portion 2b′ of reflector part 2b and a connector device 3a are received, which electrically interconnects reflector parts 2a and 2b. In a corresponding manner protruding connecting portions 2b″, 2d′, 2d″, 2f′, 2f″, 2h′ and 2h″ are received together with corresponding connector devices 3b, 3c, 3d, 3e, 3f, 3g, 3h in corresponding connecting portions 2c′, 2c″, 2e′, 2e″, 2g′, 2g″, 2i′ of adjacent reflector parts. The connector devices are disclosed in more detail in FIG. 5. The reflector parts 2a-2i are elongated and extend in a lengthwise direction (depth direction in the figure) of the reflector/antenna and are arranged in parallel side by side to form the reflector 1. The connector devices 3a-3h extend along the whole length of the reflector parts.
[0070] The reflector parts 2b, 2d, 2f and 2h are each provided with an array of antenna elements 7a, 7c, 7d, 7f (only one of each array can be seen in the shown cross section) arranged consecutively in the lengthwise direction of the antenna on the reflector. A reflector portion is formed for each array of antenna elements, wherein each reflector portion is formed by at least two reflector parts. As illustrated in the figure, a reflector portion indicated by 11′ for array 7a is formed by not only reflector part 2b to which they are connected, but also by reflector part 2a and partly reflector part 2c. In the same manner, a reflector portion indicated by 11″ for array 7c is formed by reflector parts 2c, 2d and 2e. In a corresponding manner, a reflector portion for array 7b is formed by reflector parts 2b, 2c, 2d and to some extent also 2a and 2e. It is understood that reflector portions for arrays 7d, 7e and 7f are formed in a corresponding manner. In this way, larger reflector portions than the reflector part to which said antenna elements are attached are formed. Arrays 7a, 7c, 7d and 7f each form a HB multi-radiator antenna, and arrays 7b and 7e each form a LB multi-radiator antenna.
[0071] FIG. 3 is a schematic illustration of an embodiment of a multi-array antenna arrangement according to the second or fifth aspect of the invention, which comprises the reflector and antenna elements shown in FIG. 2. The reflector parts provided with antenna elements are also provided with a respective antenna feeding network module 8a-8f being electrically connected to the antenna elements. The antenna feeding network modules each comprises a number of transmission lines having an inner conductor arranged in parallel with an elongated outer conductor with air therebetween in the form of coaxial lines, where an inner conductor (9′ for example) is surrounded by the outer conductor (9″), and where the space between is substantially air filled (apart from holding elements holding the inner conductor in position, and dielectric elements and associated parts for phase shifting purposes which are not visible in the figure). The antenna feeding network modules are formed integrally with the corresponding reflector part, for instance as an extruded aluminium profile. Antenna feeding network modules 8a, 8c, 8d and 8f are disposed substantially perpendicular to the corresponding reflector part in the sense that the inner conductors of the coaxial lines are disposed in two parallel planes which are substantially perpendicular to the corresponding reflector part. Antenna feeding network modules 8b and 8e are disposed in a conventional manner (in parallel with the corresponding reflector parts).
[0072] FIG. 4 is a schematic illustration of the multi-band antenna arrangement in FIG. 3, further provided with mechanical connectors. In this embodiment, the connector devices 3a-3h primarily function as electrical interconnectors, while mechanical rigidity in the interconnection between the reflector parts is mainly achieved by means of a mechanical connector structure formed by base plate 10d to which each reflector part and antenna feeding network module is connected by means of connectors 10a-10g.
[0073] FIG. 5 is a detail view of the interconnection between reflector parts 2b and 2c in FIGS. 2-4. It is noted that the interconnection between all adjacent reflector parts is achieved in the same manner in this embodiment. Reflector part 2c is provided with connecting portion 2c′ in the form of a cavity in which a protruding connecting portion 2b″ of reflector part 2b and a connector device 3a are received. Connector device 3a comprises two holding elements 5a and 5b. A metallic film 4 partly surrounds the periphery of holding element 5a. The metallic film 4 is arranged in abutment with connecting portions 2b″ and 2c′ of reflector parts 2b, 2c to achieve the electrical interconnection. The holding element 5a has holding portions 5a′, 5a″ connecting to the connecting portions with the metallic film 4 sandwiched therebetween. The metallic film is provided with a dielectric coating/layer 4′ arranged on the metallic film the side thereof facing the connecting portions to achieve indirect/capacitive interconnection via the film 4. The holding element 5a, 5b are non-conductive. The metallic film 4 is attached to the holding element 5a by means of an adhesive coating/layer on the side thereof facing the holding element 5a to adhere thereto. Holding element 5a is made from a resilient material to force the metallic film against the connecting portions to minimize air gaps. Holding element 5b is however not resilient to any substantial degree and only acts as a spacing and electrically insulating element. In an alternative embodiment, holding elements 5a and 5b are formed in one piece, for instance as a substantially U-shaped resilient element into which 2b″ is received.
[0074] FIG. 6 shows a cross section view of parts of an embodiment of a reflector according to the first or fourth aspect of the invention. In this embodiment, reflector parts 12a, 12b are electrically indirectly interconnected by means of a connector device 13 which comprises a holding element 15 having holding portions 15′ and 15″ at opposite end thereof which due to the shown shape and flexible and resilient material of the holding element are compressible to fit snugly into corresponding connecting portions 12a′, 12b′ of the reflector parts 12, 12b which are formed as cavities. The holding element comprises a spring portion 16 which forces the holding portions towards the connecting portions. The spring portion is formed integrally with the holding element. The metallic film 14 extends between and around the holding portions by partly surrounding the periphery of the holding element 15. The inherent flexible/bendable properties of the metallic film allow the connector device 13 to compress and expand by means of the spring portion or part to adapt to a varying distance between the reflector parts. A dielectric coating/layer 14′ is provided on the metallic film the side thereof facing the connecting portions to achieve indirect/capacitive interconnection via the film 14.
[0075] FIG. 7 shows a perspective view of the same embodiment as in FIG. 6. The connector device 13 as well as its holding element 15 and metallic film 14 extend along the full length of the reflector parts 12a, 12b.
[0076] FIG. 8 shows a cross section view of parts of another embodiment of a reflector according to the first or fourth aspect of the invention. In this embodiment, reflector parts 22a, 22b are electrically indirectly interconnected by means of a connector device 23 which comprises a holding element 25 having holding portions 25′ and 25″ at opposite end formed as cavities and being formed from the flexible and resilient material of the holding element to receive connecting portions 22a′, 22b′ of the reflector parts 22, 22b. In other words, the holding portions 25′, 25″ engage around the connecting portions 22a′, 22b′. The holding element comprises a spring portion 26 which forces the holding portions towards the connecting portions. The spring portion is formed integrally with the holding element. The metallic film 24 extends between and within the holding portions by partly surrounding the periphery of the holding element 25. The inherent flexible/bendable properties of the metallic film allow the connector device 23 to compress and expand by means of the spring portion or part to adapt to a varying distance between the reflector parts. A dielectric coating/layer 24′ is provided on the metallic film the side thereof facing the connecting portions to achieve indirect/capacitive interconnection via the film 24.
[0077] FIG. 9 shows a cross section view of parts of yet another embodiment of a reflector according to the first or fourth aspect of the invention. In this embodiment, reflector parts 32a, 32b are electrically indirectly interconnected by means of a connector device 33 which comprises two holding elements 35a, 35b, each having a respective holding portion 35a′ and 35b″ formed as cavities and being formed from the flexible and resilient material of the holding elements to receive respective connecting portions 32a′, 32b′ of the reflector parts 32, 32b. In other words, the holding portions 35a′, 35b′ engage around the connecting portions 32a′, 32b′. The metallic film 34 extends between and within the holding portions. The inherent flexible/bendable properties of the metallic film allow the connector device 33 to adapt to a varying distance between the reflector parts. A dielectric coating/layer 34′ is provided on the metallic film the side thereof facing the connecting portions to achieve indirect/capacitive interconnection via the film 34.
[0078] FIG. 10 shows a perspective view of the same embodiment as in FIG. 9. As can be seen, further identical connector devices are distributed along the length of the reflector parts.
[0079] FIG. 11 is a schematic illustration of an alternative embodiment of a multi-array antenna arrangement according to the second or fifth aspect of the invention. Just like the embodiment in FIG. 3, the antenna arrangement comprises the reflector and antenna elements shown in FIG. 2. This alternative embodiment however differs from FIG. 3 in that the antenna feeding network modules 48a-48f which are electrically connected to the antenna elements are different. Instead of coaxial lines, the modules 48a-f are formed as striplines. The transmission lines of the antenna feeding network modules comprise flat conductors/strips (49′ for example) placed between two ground planes (49″ for example). The striplines have the same function as the coaxial lines in FIG. 3. The spaces between the flat conductors/strips and the ground planes are substantially air filled. The antenna feeding network modules are formed integrally with the corresponding reflector part, for instance as an extruded aluminium profile. Antenna feeding network modules 48a, 48c, 48d and 48f are disposed substantially perpendicular to the corresponding reflector part in the sense that the flat conductors/strips are disposed in two parallel planes which are substantially perpendicular to the corresponding reflector part. Antenna feeding network modules 48b and 48e are disposed in a conventional manner (in parallel with the corresponding reflector parts).
[0080] FIG. 12 is a schematic illustration of yet an alternative embodiment of a multi-array antenna arrangement according to the second or fifth aspect of the invention. Just like the embodiment in FIGS. 3 and 11, the antenna arrangement comprises the reflector and antenna elements shown in FIG. 2. This alternative embodiment however differs from FIGS. 3 and 11 in that the antenna feeding network modules 58a-58f which are electrically connected to the antenna elements are different. Instead of coaxial lines or striplines, the modules 58a-f are formed using commonly available (bendable) coaxial cables using e.g. PTFE as dielectric. Such cables are considered well known to the person skilled in the art and are therefore not shown.
[0081] The description above and the appended drawings are to be considered as nonlimiting examples of the invention. The person skilled in the art realizes that several changes and modifications may be made within the scope of the invention.
[0082] For example, the interconnection between the reflector parts in the embodiments in FIGS. 2-4 and 11-12 can be replaced with any of the interconnections shown in FIGS. 6-10. Further, the number of arrays, reflector parts and combinations thereof can be different. Further, one or more reflector parts may be provided with two or more arrays. Also the feeding networks can be made with different combinations of transmissions lines such as those shown in FIGS. 3, 11 and 12.
