EP1588454B1 - Antenna comprising at least one dipole or dipole-like emitting device - Google Patents

Abstract

An improved antenna having at least one dipole or an antenna element arrangement which is similar to a dipole is distinguished in that the antenna element arrangement is connected capacitively and/or electrically conductively without touching to the reflector or to a reflector or a substrate which is non-conductive at least in the area in which the antenna element arrangement is attached or mounted.

Description

The invention relates to an antenna having at least one dipole or a dipole-like radiator arrangement according to the preamble of claim 1.

Dipole radiators have become known, for example, from the prior publications DE 197 22 742 A and DE 196 27 015 A. The dipole radiators can consist of a normal dipole structure or, for example, of a crossed dipole arrangement or a dipole square, etc. A so-called vector cross dipole is known from the prior art publication WO 00/39894. The structure seems to be comparable to a dipole square. However, due to the specific design of the dipole radiator according to this prior publication, a crossed dipole structure is ultimately created so that the antenna element so formed can radiate and receive in two polarizations oriented perpendicular to one another. All of these prior publications as well as the other Dipolstrukturen well-known to those of ordinary skill in the art are in this respect also made the content of the present application.

Furthermore, printing step US-A-5708446 describes a group antenna with dipole radiators on a dielectric substrate.

Object of the present invention is to provide an improved antenna with at least one dipole or dipole-like radiator, which has clearly reproducible characteristic electrical characteristics compared to conventional antennas and optionally even easier to install.

The object is achieved according to the features specified in claim 1. Advantageous embodiments of the invention are specified in the subclaims.

Whereas until now all generations of dipole radiators or dipole-like radiators have been assumed to be electrically galvanically mounted on a reflector plate, the present invention, in contrast, provides a capacitive coupling of such a radiator element to the reflector plate. With the interposition of a non-conductive element, in particular dielectric, can thereby realize a clearly reproducible in electrical terms positioning of the radiator on the reflector plate, since the intermodulation problems that may occur in the prior art may be avoided. For with a mechanical attachment of dipole or dipole-like radiator elements on the reflector sheet according to the prior art, these were usually mounted by means of screws or other connection mechanisms on the reflector sheet, which set depending on the mounting accuracy different contact conditions, with the result that intermodulation problems could occur, which expressed themselves differently.

It must also be taken into account that in the majority of cases the dipoles or dipole-like radiators are placed on the reflector plate and fastened from the back of the reflector by screwing in one or more screws. However, if, for example, the contact pressure also decreases due to the effects of heat, the contact conditions change, as a result of which the performance of such an antenna element decreases significantly.

Preferably, therefore, a dipole or dipole-like radiator with the actually radiating dipole halves and its preferably integrally connected with this balancing on an electrically non-conductive base is fixed, which in turn is fixed to the reflector plate.

It is also possible in a modification, however, that an overall electrically conductive dipole or dipole-like radiator is used, including an electrically conductive mounting base, now not an insulating intermediate socket or a non-conductive intermediate layer is used to avoid galvanic contact with the reflector, but for example the dipole or dipole-like radiator is coated or provided, at least in the region of its underlying attachment section, with a plastic layer, that is to say generally an electrically non-conductive surface.

From the above explanations it thus follows that no galvanic contact is provided between the dipole or the dipole arrangement and the reflector, but that a capacitive coupling is realized by the preferably insulated mounting. This also results in the advantage that no voltage potential can occur between the dipole and the reflector. Because of the differently selected materials for a dipole radiator or the symmetrization for a dipole radiator and the material of the reflector conventionally occurs otherwise an electrochemical stress, which can lead to contact corrosion. Since this is avoided according to the invention, there is also a greater choice of materials to be used for the dipole and / or the reflector.

In addition, according to the invention, it is also possible to use plastic dipoles which only have a partial metallization, ie in particular are not metallized in their contact and connection region to the reflector. The balancing is preferably understood to be electrically conductive as part of the dipole arrangement.

Finally, the inventive principle also results in a separation of the mechanical and electrical functions. There are now no high contact or surface pressures necessary because an always permanent electrical contact connection between the dipole or its symmetry at the reflector is no longer necessary.

Finally, a dipole arrangement according to the invention can also be plugged directly onto a platinum carrier, so that in such a case no additional plastic part is necessary. A feed could be done here directly on the back of the board structure on which the matching structure is provided.

The principle explained applies to all types of dipoles, vertical dipoles, X-shaped polarized dipoles (ie at a ± 45 ° angle to the horizontal) for single-band, dual-band antennas or dipole structures, in particular square dipole structures in which multiple radiators are arranged in each other, which are provided for different frequency bands.

In a particularly preferred embodiment, a suitable stamping is provided in the reflector sheet into which the mounting base of the radiator element, for example, clipped, inserted and then rotated into the final fixing position, etc. can be. It can be used here closure and fastening mechanisms, as they are known, for example, in the manner of so-called. Bayonet locks including all related modifications.

Figur 1 :

eine schematische perspektivische Darstellung eines erfindungsgemäßen Ausführungsbeispieles der Erfindung;

Figur 2 :

eine weitere perspektivische Darstellung der Strahleranordnung gemäß Figur 1 auf einem Reflektor, jedoch von einer leicht rückwärtigen Ansicht;

Figur 3 :

eine vertikale Querschnittsdarstellung durch das Ausführungsbeispiel gemäß Figuren 1 und 2;

Figur 4 :

eine schematische perspektivische Darstellung einer Antennenanordnung mit drei vertikal übereinander angeordneten Strahlern; und

Figur 5 :

eine schematische Draufsicht auf einen Reflektor mit einer dort eingebrachten Öffnung zur Fixierung eines Sockels einer in den Figuren 1 bis 4 gezeigten Strahleranordnung.

Figur 6:

ein abgewandeltes Ausführungsbeispiel zu den Figuren 1 und 3.

The invention will be explained in more detail with reference to drawings. In detail:

FIG. 1:

a schematic perspective view of an embodiment of the invention according to the invention;

FIG. 2:

a further perspective view of the radiator arrangement according to Figure 1 on a reflector, but from a slightly rear view;

FIG. 3:

a vertical cross-sectional view of the embodiment of Figures 1 and 2;

FIG. 4:

a schematic perspective view of an antenna assembly with three vertically stacked radiators; and

FIG. 5:

a schematic plan view of a reflector with an opening there introduced for fixing a base of a radiator arrangement shown in Figures 1 to 4.

FIG. 6:

a modified embodiment of Figures 1 and 3.

FIG. 4 shows an antenna arrangement 1 in a schematic representation with a reflector or reflector sheet 3. The reflector 3 may preferably be provided at its two opposite longitudinal sides 5 with a reflector boundary 3 ', which may for example be aligned perpendicular to the plane of the reflector sheet 3 or in a deviating from a right angle, oblique angle.

Usually, a plurality of dipoles or dipole-like radiators are arranged on such a reflector sheet 3 in the vertical direction offset from one another. The radiator or radiator arrangements 7 can consist of single-band radiators, dual-band radiators, triple-band radiators or the like. In today's generation of antennas, dual-band radiators or even triple-band radiators are preferably used which, in addition, can transmit and / or receive in two orthogonally oriented polarizations, and which preferably have an angle of ± 45 ° the horizontal or vertical are aligned. Reference is made in particular to the prior publications DE 197 22 742 A and DE 196 27 015 A, which show and describe different antennas with a wide variety of emitter arrangements. All these radiator and radiator elements and other modifications can be used and used in the context of the present invention. Therefore, it is thus also possible to use emitters with a true dipole structure, in the manner of a crossed dipole, of a dipole square or in the manner of its so-called vector dipole, as are known, for example, from WO 00/39894. All of these types of radiators and modifications are incorporated herein by reference to the above prior publications.

In the figures 1 to 3 in greater detail in different representations, a first inventive radiator assembly 11 on a reflector 3 is shown. The emitter assembly 11 has in principle a structure, as it is known from WO 00/39894 and described in detail in this Vorveröffentlichung. Reference is therefore made in its entirety to the disclosure content of the above publication and made the content of this application. From this it is known that the radiator arrangement 11 according to the embodiments of Figures 1 to 4 in a schematic plan view, although designed as a dipole square, but due to the specific training, however, sends and receives in electrical terms as a Kreuzdipol. In FIG. 4, with respect to a radiator arrangement 11, the two polarization directions 12a and 12b are shown, which are perpendicular to one another and formed by the diagonal radiator arrangement 11 which is formed more quadratically in plan view.

Each of the 180 ° opposite structures according to the radiator arrangement 11 act insofar as dipole halves of two cross-shaped dipoles.

A so-formed dipole-shaped radiator 11 is held and mounted on the reflector 3 via the associated balancing 15. The dipole halves 13 and the symmetrization 15 are made of electrically conductive material, usually metal or metal alloy.

In order to ensure now a capacitive coupling on the reflector sheet 3, that is to provide an electrically non-contact connection, a base 17 is provided which consists of non-conductive material, such as plastic, a dielectric, etc. About this base 17 of the associated base portion 15 'of the balancing 15 is fixed and held. The base 17 is now in turn anchored in a recess 19 (Figure 5) in the reflector plate 3. This can take place, for example, in that the base 17 has in particular radially projecting, ie laterally projecting projections 17 'and setback portions 17 ", so that the socket with this shape can be inserted into a correspondingly shaped recess 19 in the reflector plate the entire arrangement, for example, be rotated by an angle of about 30 ° or 45 ° until the final alignment position is reached, in which a preferably non-positively secure position of the base 17 is provided with respect to the recess 19 by the on the back or Underside of the reflector 3 radially projecting projections engage under the corresponding material portions of the reflector, whereas other projections above 17 'parts of the reflector sheet overlap from above, thus fix the emitter assembly 11 safely. If required, additional, even positive fixing can be used to ensure a secure fit. Finally, even screws can be screwed through the plastic base, which also enforce the reflector plate, for example, in a separate hole and electrically conductive but not get in touch with the radiator arrangement of balancing.

Since the base is made of plastic and thus the symmetry and the radiator assembly 11 is completely separated and isolated from the electrically conductive reflector or reflector plate 3 through the base, this results in a capacitive coupling.

As an alternative to the illustrated embodiment, instead of the reflector sheet 3, a circuit board structure 3 'or another substrate 3' may be provided which is nonconductive or non-conductive, at least in the anchoring region of the base or the radiator. This is reproduced in a schematic, partially cross-sectional representation according to FIG. Conductive structures on the underside of the board, especially large-area conductive structures 31 on the board for producing a reflector or a reflector-like metallization can be provided on the top or the bottom of the substrate or the board 3 ', but should not extend into the Attachment range of the symmetrization of a radiator 7 and a radiator assembly 11 range. In this case, so can be dispensed with an electrically non-conductive socket. The radiator with its radiator structure can be directly on the non-conductive Substrate or the non-conductive board structure can be placed and anchored. In this case, the substrate may preferably be formed from a printed circuit board, on whose rear side the electrically conductive matching structures are formed, without a galvanic coupling of the balancing being provided.

Likewise, a modification is possible to the extent that the entire radiator including the balancing also again consists of electrically conductive material, in this embodiment, the base portion 15 'of the radiator assembly is coated with an electrically non-conductive material, plastic or a dielectric and fixed thereto on the reflector sheet becomes. This also ensures a capacitive, so electrically non-conductive non-contact connection to the reflector sheet.

Conversely, however, the radiator arrangement or at least the symmetrization can be formed entirely or substantially of nonconductive material, which is then coated with a conductive structure, in particular a metallizing layer. Excluded from this metallic conductive surface structure are only those anchoring sections, with which the thus formed radiator 11 is mounted, for example, on a conductive reflector 3 in order to avoid a galvanic-electrical connection.

Claims (4)

1. Antenna having an antenna element arrangement (11) which is similar to a dipole, preferably in the form of at least one dipole, with the antenna element arrangement (11) which is similar to a dipole being capacitively connected to the reflector, and having the following features:

   - a cap section (15') of a balancing device (15) is connected to an electrically non-conductive cap (17),

   - the cap (17) is fixed on the electrically conductive reflector (3),

   - the antenna element arrangement (11) is capacitively connected to the reflector (3) with the interposition of the cap (17) or is connected to it without any conductive electrical contact;

   characterized by the following features:

   - the reflector (3) has a recess (19) in which the cap (17), which at least partially passes through the recess (19), engages and is anchored.
2. Antenna according to Claim 1, characterized in that the reflector (3) or a substrate (3'), to which the antenna element arrangement (11) is fitted, has or comprises a board structure, on whose rearward face, which faces away from the antenna element arrangement (11), a matching structure is preferably provided.
3. Antenna according to Claim 1 or 2, characterized in that the cap (17) is designed as a plug-in and/or rotary connection attachment device, which can be mechanically fixed to the reflector (3) by insertion and rotation.
4. Antenna according to one of Claims 1 to 3, characterized in that the reflector (3) is composed of an electrically non-conductive substrate (3'), which preferably has a board structure and is entirely or partially provided with an electrically conductive layer (31) in order to produce a reflector effect.

Images