Antenna System

Abstract

An antenna system (10) includes at least one antenna (12), a feed line (18), and a cable guide (30) for a cable (32) that does not feed the at least one antenna (12). The at least one antenna (12) has a feed section (20) to which the feed line (18) is distributed. The cable guide (30) has an opening (34) arranged in the feed section (20).

Description

Technical Field

[0001] The invention provides an antenna system, in particular an omnidirectional antenna system. Background Art

[0002] In antenna systems, it is often necessary to provide two or more antennas in a limited space (eg, a housing). Installing these antennas in a limited space is difficult because the antennas must be fed with signals without interfering with the radiation patterns of the antennas.

[0003] Positioning two or more antennas, especially omnidirectional antennas, adjacent to each other will result in the overall radiation pattern being disturbed, since the antennas interfere with each other. Furthermore, interference also occurs due to the fact that the corresponding feeder of a certain antenna is routed in front of another antenna and thus the feeder interferes with the radiation pattern from the latter antenna in the direction in which the feeder is positioned. However, these problems do not only occur in antenna systems having a plurality of antennas to which signals are supplied, but also occur with antenna systems comprising electrical loads or other components to which signals or power are supplied for operating purposes.

[0004] Typically, the corresponding wires or cables routed to the upper antenna or more precisely to the electrical load should have a small length in order to reduce the impact of cable losses due to excessive length of the wires or cables. In fact, the length also has an impact on the radiation performance of the antenna system.

[0005] In addition to electrical components, other components may also be connected to the cable which have an influence on the radiation pattern of the at least one antenna, for example liquid lines or gas lines.

[0006] Therefore, there is a need for an antenna system that provides optimized radiation performance. Summary of the invention

[0007] The invention provides an antenna system, which comprises at least one antenna, a feeder and a cable guide for a cable that does not feed the at least one antenna. The at least one antenna has a feed portion to which the feeder is distributed. The cable guide has an opening arranged in the feed portion.

[0008] Thus, the cable guide ensures that the cables of the antenna system, which cables do not feed at least one antenna, are routed in an optimized manner. In fact, the opening of the cable guide is positioned in the feed section of the at least one antenna so that the cables are routed through the feed section of the at least one antenna. This ensures that the corresponding cable length of the cables that do not feed the at least one antenna can be minimized while at the same time having a minimized impact on the emission pattern of the at least one antenna.

[0009] The cable guide also ensures that the cable does not have to be guided in front of the at least one antenna, i.e. in front of its aperture, which would result in a disturbing emission pattern of the at least one antenna. Instead, the cable guided by the cable guide is routed within the feed section, in particular along the central axis of the at least one antenna, so as to have a minimal impact on the emission pattern of the at least one antenna. When the cable is routed along the central axis of the at least one antenna, in particular the entire antenna system, the length of the cable is minimized, resulting in minimized cable losses.

[0010] In fact, the cable guide is positioned in the feed part of at least one antenna, wherein the feed part refers to the part of at least one antenna for conducting electromagnetic waves emitted by at least one antenna. In other words, the feed part is electrically connected to the feed line. Thus, the electrical signal is forwarded to the at least one antenna, i.e. its feed part, via the feed line. The feed part converts the electrical signal received via the feed line into an electromagnetic wave to be emitted in the air (e.g. in an omnidirectional manner).

[0011] The antenna system may comprise a cable which does not feed at least one antenna, in particular at least one antenna having a cable guide positioned in its feeding portion.

[0012] This corresponding antenna, ie the antenna having the cable guide positioned in its feed section, may be referred to as the first antenna.

[0013] Therefore, the cable guide is provided for cables which do not feed the first antenna.

[0014] Typically, the feed section may correspond to a coaxial feed section, which comprises an inner conductor and an outer conductor.

[0015] Therefore, the feeding part can be realized by the antenna itself, the coaxial waveguide or the coaxial cable.The coaxial waveguide or more precisely the coaxial cable can be involved in the interface for the feed line.

[0016] In particular, the cable guide is assigned to the inner conductor and the outer conductor. In other words, the cable guide has at least two openings, of which at least one opening is arranged in the outer conductor and at least one opening is arranged in the inner conductor. The openings assigned to the inner conductor and the outer conductor can be oriented such that they are aligned relative to each other, in particular with respect to the orientation of the cable guided by the cable guide.

[0017] Therefore, the feed section, for example a coaxial feed section, is penetrated by the cable.

[0018] The respective cable may correspond to a coaxial cable, a power cable, a hollow conductor, a tube, a wire or any other suitable kind of cable which may be routed to another antenna, a component of an antenna system or rather an electrical load.

[0019] The cable may have an outer surface at least partially comprising an electromagnetically conductive material. Thus, the cable need not necessarily have electrical insulation around its periphery.

[0020] Typically, electromagnetic signals or a medium such as a liquid or a gas can be conducted by means of the cable.

[0021] According to one aspect, the feed section has an axial end to which the feed line is connected. Thus, the feed line can be easily connected to the feed section of at least one antenna via the axial end of the feed section because the axial end is easily accessible.

[0022] Furthermore, the openings may be positioned at the lateral sides of the feed section. This ensures that the cable guide has at least a minimal interaction with the feed line, preferably it does not interact with the feed line, since the cable routed via the cable guide does not feed the at least one antenna. In fact, the cable is only routed through the openings provided in the feed section, i.e. in the lateral sides thereof. The lateral sides are substantially perpendicular to the axial ends of the feed section to which the feed line is connected.

[0023] In particular, the opening has a central axis that is tilted at a certain tilt angle relative to the lateral side of the feed portion. The tilt angle can range from 5° to 85°, so that the cable routed through the opening of the cable guide is guided to a specific direction due to the tilt of the opening relative to the lateral side.

[0024] However, it is also possible for the opening to have no inclination relative to the lateral sides.

[0025] According to one aspect, at least one antenna has a flared horn portion and a central axis, wherein the opening is oriented in the feed portion so that the cable guided through the opening runs substantially along the central axis in the space confined by the flared horn portion. Due to the shape of the flared horn portion (i.e. the substantially circular cross-section), the flared horn portion can be a cone or more precisely a truncated cone. Corresponding cable guides positioned in the feed portion, in particular in its lateral sides, ensure that the cable runs through the flared horn portion substantially in the middle thereof, so that it has a minimal impact on the generated electromagnetic waves, i.e. the emission pattern of the at least one antenna.

[0026] The central axis of the at least one antenna may correspond to the axis of symmetry. This ensures that the influence of a cable routed along the central axis of the at least one antenna has an evenly distributed influence on the emission pattern, which influence is minimized overall.

[0027] In particular, the central axis relates to the rotational symmetry axis of the at least one antenna. Thus, at least the flared horn section is rotationally symmetrical. For example, the flared horn section has a cone shape or more precisely a frustum shape. As described above, the influence of the cables routed along the central axis in the flared horn section is evenly distributed.

[0028] On the other hand, a feeding part is provided, comprising a waveguide section and a feeding point. The feeding point of the feeding part is directly electrically connected to the feed line, while the waveguide section of the feeding part surrounds the feeding point. In fact, the feeding point is assigned to the axial end of the feeding part. When an electrical signal is provided to the feeding part, an electromagnetic wave is generated by means of the feeding part, in particular the waveguide section and the feeding point. The generated electromagnetic wave propagates along the waveguide section to be emitted. In fact, the waveguide section can be established by the lateral side of the feeding part. Therefore, the opening of the cable guide is positioned in the waveguide section.

[0029] The waveguide section may be a coaxial waveguide section. This means that the coaxial waveguide section comprises an inner conductor, ie an inner waveguide part, and an outer conductor, ie an outer waveguide part.

[0030] The waveguide section may comprise an electromagnetically conductive section. The electromagnetically conductive section may relate to a lateral side or more precisely a lateral wall of the feed portion. The generated electromagnetic waves propagate along the lateral sides or more precisely the lateral walls of the feed portion, ie the electromagnetically conductive section.

[0031] In particular, the opening is provided in the electromagnetically conductive section.The opening is positioned in a side wall or a transverse wall of the electromagnetically conductive section.

[0032] According to another aspect, the electromagnetically conductive section partially merges into the flared horn section. In other words, the waveguide section at least partially merges into the flared horn section. The flared horn section is also electromagnetically conductive. Therefore, the electromagnetic waves generated in the feed section of at least one antenna propagate along the waveguide section, in particular at least partially along the flared horn section.

[0033] In other words, the aperture of the at least one antenna is at least partially arranged at the end of the flared horn portion, via which the electromagnetic waves are emitted into the environment, for example in an omnidirectional manner.

[0034] On the other hand, a cable guide is provided with a plurality of openings for a plurality of cables. Thus, more than one cable can be routed through the cable guide, in particular along the central axis of the at least one antenna. More than one cable can be assigned to different antennas and / or electrical loads stacked on top of each other. In fact, it is ensured that media, signals and / or power can be forwarded to components positioned above the at least one antenna via the cables routed along the cable guide.

[0035] The cables are routed through the feed section and within the flared horn section of at least one antenna, which results in minimal disturbance of the radiation pattern and minimal cable length of the corresponding cables, resulting in minimal cable losses.

[0036] Therefore, the cable is routed along the central axis of the at least one antenna over the entire flared horn portion of the at least one antenna. In other words, the cable is routed in an inclined manner within the waveguide section relative to the central axis.

[0037] At least one antenna may be a coaxial horn antenna. Thus, at least one antenna is fed via a coaxial cable in order to receive a corresponding signal, which is converted into an electromagnetic wave in order to be emitted in an omnidirectional manner by the coaxial horn antenna.

[0038] As mentioned above, the feed section may involve a coaxial feed section comprising an inner conductor and an outer conductor.

[0039] Thus, in addition to the flared horn portion, the coaxial horn antenna may include a designated antenna portion. In fact, the inner conductor is connected to the flared horn portion, while the outer conductor is connected to the designated antenna portion. In other words, the inner conductor may merge into the flared horn portion, while the outer conductor may merge into the designated antenna portion.

[0040] However, the outer conductor can also be connected to or more precisely merge into the flared horn section, while the inner conductor is connected to or more precisely merges into the designated antenna section.

[0041] Typically, a coaxial antenna, also commonly referred to as a coaxial dipole, is a specific form of a half-wave dipole antenna. Typically, a coaxial antenna is used as a vertically polarized omnidirectional antenna.

[0042] Thus, the antenna system may involve an omnidirectional antenna system, wherein at least one antenna is an omnidirectional antenna. Thus, the electromagnetic waves generated by the antenna system are emitted into the environment in an omnidirectional manner.

[0043] Furthermore, the antenna system may have a first antenna and a second antenna stacked on each other. The two antennas may share a common central axis, wherein the central axis may relate to the axis of symmetry. Since the cable is routed along the cable guide so that it runs substantially along the central axis in the space limited by the flared horn portion of the first antenna, it is ensured that the cable losses are minimized because the length of the cable routed to the second antenna is minimized. At the same time, it is ensured that the emission pattern is disturbed only in a minimized manner.

[0044] Furthermore, the second antenna may be a biconical antenna. A biconical antenna is also called a biconical antenna. In fact, a biconical antenna has a symmetry plane from which two substantially similar conductive objects (eg cones) extend in opposite directions.

[0045] Typically, the antenna system, in particular each of the antenna(s), has a wide bandwidth. However, the antenna system, in particular each of the antenna(s), may also have a narrow bandwidth. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The above-described aspects and many of the attendant advantages of the present subject matter will become more readily appreciated, as the said aspects and advantages are better understood, by reference to the following detailed description when taken in conjunction with the accompanying drawings, in which:

[0047] Figure 1 Schematically showing a cross-sectional view of an antenna system according to a first embodiment of the present invention,

[0048] Figure 2 schematically shows an isometric view of an antenna system according to the invention,

[0049] Figure 3 Schematically shows Figure 2 A cross-sectional view of the antenna system shown in FIG.

[0050] Figure 4 A cross-sectional view schematically showing details of an antenna system according to a second embodiment of the invention,

[0051] Figure 5 shows an isometric view of an antenna system according to another embodiment of the present invention, without the feed line of the first antenna,

[0052] Figure 6 Shows Figure 5 A cross-sectional view of the antenna system shown,

[0053] Figure 7 Shown according to Figure 5 and 6 Side view of an antenna system with the cables being guided in a cable guide,

[0054] Figure 8 Shows Figure 7 A cross-sectional view of the antenna system shown,

[0055] Fig. 9 shows details of an antenna system according to the invention,

[0056] Fig.10 In the first example, Fig. 9 A cross-sectional view of

[0057] Fig.11 In the second example, Fig. 9 Cross-sectional view of . DETAILED DESCRIPTION

[0058] The detailed description set forth below in conjunction with the accompanying drawings (in which like reference numerals represent like elements) is intended as a description of various embodiments of the disclosed subject matter and is not intended to represent the only embodiments. Each embodiment described in this disclosure is provided only as an example or illustration and should not be construed as superior or preferred over other embodiments. The illustrative examples provided herein are not intended to be exhaustive or to limit the claimed subject matter to the precise form disclosed.

[0059] exist Figures 1 to 3 , an antenna system 10 according to a first embodiment is shown, which includes a first antenna 12 and a second antenna 14 stacked on each other.

[0060] The antenna system 10 is an omnidirectional antenna system because the antennas 12 , 14 are both omnidirectional antennas.

[0061] In fact, the first antenna 12 corresponds to a coaxial horn antenna, whereas the second antenna 14 corresponds to a biconical antenna, as will be described in more detail below.

[0062] exist Figure 1 In the embodiment, the antenna system 10 includes a housing 16 in which the first antenna 12 and the second antenna 14 are positioned. Figure 2 and 3 In the illustration of FIG. 1 , the housing 16 is not shown.

[0063] The antenna system 10 further includes a feed line 18 electrically connected to the first antenna 12 so as to forward the electrical signal to the first antenna 12 .

[0064] The first antenna 12 includes a feed portion 20 to which a feed line 18 is connected. The feed portion 20 of the first antenna 12 is generally configured to generate electromagnetic waves that are emitted by the antenna system 10, as will be described later.

[0065] Typically, the feed section 20 corresponds to a coaxial feed section having an inner conductor and an outer conductor, as will be described with reference to FIG. Figures 9 to 11 Described in more detail.

[0066] like Figure 1 As shown, the feed line 18 is connected to an axial end 22 of a feed part 20 , which merges into a cylindrical, in particular circular cylindrical, waveguide section 24 .

[0067] The feed section 20 also has a feed point 26 which is surrounded by the waveguide section 24 .

[0068] In fact, the feed point 26 is electrically connected to the feed line 18 in order to receive an electrical signal forwarded via the feed line 18. The feed point 26 electromagnetically interacts with the waveguide section 24, in particular the electromagnetically conductive section of the waveguide section 24, in order to generate electromagnetic waves.

[0069] The electromagnetic wave propagates along the waveguide section 24 toward the open end of the first antenna 12, that is, the aperture A of the first antenna 12. Figure 1 , 3 As shown by the corresponding lines in 4 and 5, electromagnetic waves are emitted through the aperture in an omnidirectional manner.

[0070] The waveguide section 24 partially merges into a flared horn portion 28, at the opposite end of which the open end is provided. The flared horn portion 28 widens toward the open end.

[0071] The waveguide section 24 also partially merges into a designated antenna section 29. Figure 1 , 3 As shown in FIG. 4 , the electromagnetic wave to be emitted propagates between the flared horn portion 28 and the designated antenna portion 29 .

[0072] As shown in these drawings, the inner conductor of the coaxial feed section 20 is connected to the flared horn section 28 , and the outer conductor of the coaxial feed section 20 is connected to a designated antenna section 29 .

[0073] The flared horn portion 28 and / or the designated antenna portion 29 are rotationally symmetrical, so that the central axis C corresponds to the axis of symmetry. In fact, the flared horn portion 28 may have the shape of a cone, or more precisely the shape of a frustum of a cone.

[0074] The antenna system 10 further comprises a cable guide 30 for a cable 32 that does not feed the first antenna 12 .

[0075] like Figure 1 and 3 As shown, the cable 32 is guided to the second antenna 14 via the cable guide 30. Therefore, the cable 32 may correspond to a feed line of the second antenna 14 stacked on the first antenna 12.

[0076] However, the cable 32 may also correspond to a power cable of an electrical load or any other power consuming component positioned on top of the first antenna 12 .

[0077] In fact, the cable 32 can be any type of cable. Therefore, the cable 32 can correspond to a coaxial cable, a power cable, a hollow conductor, a tube, a wire, or any other kind of cable that can be guided or routed by the cable guide 30 positioned in the feed portion 20 of the first antenna 12.

[0078] In general, the cable 32 may be used to conduct electromagnetic signals or a medium such as a liquid or a gas.

[0079] The cable guide 30 has at least one opening 34 provided in the feed portion 20 of the first antenna 12. The opening 34 is positioned in a lateral side 36 of the feed portion 20 corresponding to the waveguide section 24.

[0080] The at least one opening 34 has a central axis O that is inclined at an inclination angle relative to a lateral side 36 of the feed section 20. The inclination angle may range from 5° to 85°.

[0081] This inclination generally ensures that the cable 32 is routed along the cable guide 30 , in particular the opening 34 thereof, such that the cable 32 runs towards the central axis C of the first antenna 12 .

[0082] Since the feed section 20 is a coaxial feed section, two openings 34 assigned to the inner conductor and the outer conductor are provided, as will be described later with reference to FIG. Figures 9 to 11 This ensures that the cable 32 can be guided from the external environment of the feed section 20 into the space defined by the inner conductor of the coaxial feed section 20 .

[0083] like Figure 1 and 3 As shown, the cable 32 runs along the central axis C within the flared horn portion 28 of the first antenna 12 . In other words, the cable 32 runs along the central axis C of the first antenna 12 substantially within the space defined or confined by the flared horn portion 28 .

[0084] Therefore, the cable length of the cable 32 extending along the central axis C is minimized. This avoids cable losses due to excessive length of the cable 32. In addition, since the cable 32 extends along the central axis C within the flared horn portion 28 of the first antenna 12, the emission pattern of the first antenna 12 is minimally disturbed, so that its influence on the emission pattern is symmetrical or, more precisely, uniformly distributed.

[0085] exist Figure 4 , an alternative embodiment is shown, wherein the cable guide 30 comprises a plurality of openings 34, namely at least four openings 34, which are arranged in the respective feed section 20, namely at opposite lateral sides 36 and within the inner and outer conductors of the coaxial feed section 20.

[0086] Thus, more than one external cable 32 , ie more than one cable that does not feed the first antenna 12 with the cable guide 30 , is provided so that these cables 32 can be routed through the feed portion 20 of the first antenna 12 .

[0087] Thus, three or more antennas may be stacked on top of each other.In addition, a plurality of electrical loads or other components may be positioned on top of the first antenna 12 having the cable guide 30 in the feed portion 20 thereof.

[0088] exist Figures 5 to 8 In the embodiment, the antenna system 10, in particular the first antenna 12 including the cable guide 30, is shown in different views, in particular without ( Figure 5 and 6 ) and have ( Figure 7 and 8 ) in the case of an external cable 32 routed via the cable guide 30. Therefore, the corresponding routing of the external cable 32, ie the cable that does not feed the first antenna 12, is clearly visible.

[0089] Typically, the opening 34 of the cable guide 30 is positioned in the feed portion 20 of the first antenna 12 , ie, within a lateral side 36 of the waveguide section 24 .

[0090] Thus, the opening 34 is provided in a conductive section of the waveguide section 24 which electromagnetically interacts with the feed point 26 which in turn is connected to the feed line 18 for receiving the electrical signal converted into an electromagnetic wave.

[0091] Therefore, the cable 32 routed via the cable guide 30 interferes with the radiation pattern of the first antenna 12 in a minimized manner.

[0092] Furthermore, the overall emission pattern of the antenna system 10 is disturbed in a minimized manner, since the respective antennas 12 , 14 are stacked on top of each other while being omnidirectional antennas, thereby forming the omnidirectional antenna system 10 .

[0093] exist Figures 9 to 11 , the feed section 20 is shown in more detail. The feed section 20 shown in these figures may be related to the feed section shown in the previous figures (wherein the antenna system 10 is shown).

[0094] In particular, it is apparent that the feed section 20 of the first antenna 12 involves a coaxial feed section, since it comprises an inner conductor 38 and an outer conductor 40 .

[0095] Thus, the waveguide section 24 is also coaxial in that it at least partially includes the inner conductor 38 and the outer conductor 40 .

[0096] The cable guide 30 includes two openings 34 , of which a first opening 34 a is provided in the outer conductor 40 and a second opening 34 b is provided in the inner conductor 38 .

[0097] like Fig.10 and 11 As shown, when the cable 32 is routed through the corresponding opening 34 , the feed portion 20 , ie, the inner conductor 38 and the outer conductor 40 , are penetrated by the cable 32 .

[0098] The cable 32 guided through the opening 34 can be (electrically) connected to the first opening 34 a and / or the second opening 34 b , ie the corresponding opening 34 in the inner conductor 38 and / or the outer conductor 40 .

[0099] In other words, the cable 32 , in particular its electromagnetically conductive outer surface portion, may be electrically connected to the inner conductor 38 and / or the outer conductor 40 by means of the edges of the corresponding openings 34 .

[0100] The corresponding electrical connections may depend on the properties to be achieved.

[0101] In the case of two electrical connections (i.e., the electrical connection between the cable 32 and the inner conductor 38 and the electrical connection between the cable 32 and the outer conductor 40), a ferrite member 42 (e.g., a ferrite ring) may be provided, such as Fig.11 shown.

[0102] In any case, it is ensured that at least one cable 32 is guided through the feed section 20 of at least one antenna 12 by means of the cable guide 30 .

[0103] The feed section 20 may be a coaxial feed section, so that the cable 32 runs through the opening 34 of the cable guide 30 assigned to the inner conductor 38 and the outer conductor 40. In other words, the cable 32 penetrates the inner conductor 38 and the outer conductor 40 so as to reach the center axis C.

[0104] The cable 32 is then guided along the central axis C towards the open end of the flared horn portion 28 in order to interfere with the overall emission pattern of the antenna system 10 , in particular the first antenna 12 , in a minimized manner.

[0105] Thus, an omnidirectional antenna system 10 is provided which has an optimized radiation pattern, since cable losses, in particular cable losses for feeding the second antenna 14, are minimized and the radiation pattern of each antenna 12, 14 is disturbed in a minimized manner. Thus, the overall radiation performance of the antenna system 10 is improved.

[0106] In general, the features and characteristics of the different embodiments shown may be combined in any desired way.

Claims

1. An antenna system (10) comprising at least one antenna (12), a feeder line (18) and a cable guide (30) for a cable (32) that does not feed the at least one antenna (12), wherein: The at least one antenna (12) has a feed section (20) to which the feed line (18) is assigned, and wherein the cable guide (30) has an opening (34) arranged in the feed section (20), The at least one antenna (12) has a flared horn portion (28) and a central axis (C), wherein the opening (34) is oriented in the feed portion (20) so that a cable (32) guided through the opening (34) extends substantially along the central axis (C) in a space limited by the flared horn portion (28).

2. The antenna system (10) according to claim 1, characterized in that The feed portion (20) has an axial end (22) to which the feed line (18) is connected.

3. The antenna system (10) according to claim 1 or 2, characterized in that The opening (34) is positioned at a lateral side (36) of the feed portion (20).

4. The antenna system (10) according to claim 3, characterized in that The opening (34) has a central axis (O) which is inclined at an inclination angle relative to a lateral side (36) of the feed portion (20).

5. The antenna system (10) according to claim 1 or 2, characterized in that The central axis (C) is associated with an axis of rotational symmetry of the at least one antenna (12).

6. The antenna system (10) according to claim 1 or 2, characterized in that The feeding portion (20) includes a waveguide section (24) and a feeding point (26).

7. The antenna system (10) according to claim 6, characterized in that The waveguide section (24) comprises an electromagnetically conductive section.

8. The antenna system (10) according to claim 7, characterized in that The opening (34) is provided in the electromagnetically conductive section.

9. The antenna system (10) according to claim 7, characterized in that The electromagnetically conductive section partially merges into the flared horn portion (28).

10. The antenna system (10) according to claim 1 or 2, characterized in that The cable guide (30) has a plurality of openings (34) for a plurality of cables (32).

11. The antenna system (10) according to claim 1 or 2, characterized in that The at least one antenna (12) is a coaxial horn antenna.

12. The antenna system (10) according to claim 1 or 2, characterized in that The antenna system (10) is an omnidirectional antenna system, wherein the at least one antenna is an omnidirectional antenna.

13. The antenna system (10) according to claim 1 or 2, characterized in that The antenna system (10) has a first antenna (12) and a second antenna (14) stacked on each other.

14. The antenna system (10) according to claim 13, characterized in that The second antenna (14) is a biconical antenna.

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