EP1881551A1 - Wave guide manifold - Google Patents

Abstract

The elbow has hollow conductor-connecting pieces (1) including an inner-cross section with an edge length (a), where an angle section that results ninety degree-direction change is provided between the connecting pieces. The angle section has a chamfer as a boundary wall for the elbow, where a hollow conductor-channel is outwards limited by the chamfer. The chamfer has a length in a bending level, which corresponds to the edge length of the connecting pieces.

Description

The invention relates to a waveguide header according to the preamble of claim 1.

Waveguides are known to be used in microwave technology. Waveguides represent the basic element in waveguide technology. Waveguides are available in various lengths, cross-sectional shapes and sizes. Hollow waveguides often have a rectangular cross section. But also round cross-sectional shapes for waveguides are known. Usually, such waveguides are provided at the beginning and at the end with a flange so as to connect successive waveguide sections firmly together. In a waveguide section usually the cross section is obtained. But also transitions from one cross-sectional shape to another cross-sectional shape are known.

Frequently, the task arises to provide a direction change in a waveguide route. For this purpose, so-called waveguide headers or waveguide angles are used. Most of these are 90 ° elbows, where the direction of the electric field lines (E-bend, E-angle), so in the rectangular waveguide on the broadside, or the direction of the magnetic field lines (A-bend, A-angle), so in rectangular waveguides in the direction of the narrow side changes ,

Such waveguide manifolds are basically from the publication " Erich Pehl, Microwave Technology, Volume 1, Waveguides and Line Components, Dr. med. Alfred Hütig Verlag Heidelberg, 1988, pages 172-175 "as well as, for example" Walter Jansen, waveguide and stripline, dr. Alfred Hütig Verlag Heidelberg, 1977, pages 101 to 104 Here, in the aforementioned prior publication of "Walter Jansen" with reference to Figure 6.1 b, a so-called H-manifold and with reference to Figure 6.1 c, a so-called e-manifold reproduced.

A 90 ° -Hohlleiterkrümmer is also from the EP 0 285 295 A1 known. The 90 ° waveguide manifold has an edge length according to an embodiment of Figure 2 of this prior publication, which is indicated with a size of 0.900 inches. To optimize the waveguide bulk while reducing the attenuation, the length L from the beginning of the bevel to the 90 ° corner point in the case of optimizing the E-plane waves is 0.700 inches and for optimizing the H-plane wave is 0.642 inches at one edge length of the waveguide cross section of 0.900 inches.

Object of the present invention is based on the above-mentioned generic state of the art with a square in cross section waveguide To provide a 90 ° -Hohlleiterkrümmer, ie a 90 ° -Hohlleiterwinkel, which should be produced by casting, with a cost-effective and reliable adaptation to existing LNB's should be possible, and this with respect to the prior art again improved electrical properties in terms the propagation of the electromagnetic waves (ie both the E and the H-plane waves) in the waveguide.

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

The invention provides a 90 ° -Hohlleiterkrümmer, which can be used due to its square waveguide cross-section equally as E-manifold for electric field lines or as H-manifold for magnetic field lines.

In a square waveguide as provided in the invention, basically two mutually orthogonal modes are capable of propagation. Typically, however, with such a square cross-sectional 90 ° bend, there would be reflux and transmission loss which would result in insufficient electrical values for practical use.

It is therefore customary in the prior art to guide both mutually perpendicular modes separately via their own rectangular waveguide or both modes together via a circular waveguide. A round waveguide has the disadvantage that relatively large bending radii necessary are, ie a space-saving 90 ° -Knick is not feasible.

The inventive 90 ° waveguide bend is particularly suitable for a frequency range of 10.7 to 12.75 GHz, namely for vertical and horizontal polarization (parallel alignment to the two mutually perpendicular axes of the square cross-section of the waveguide).

The waveguide bend according to the invention can be used with equally good properties for other frequency ranges comparable comparable bandwidth (around +/- 10% relative to the center frequency). Decisive is the edge length of the waveguide, which then has to be scaled accordingly. For the specified frequency range, the edge length is e.g. 15 mm.

It is surprising that within the scope of the invention a waveguide manifold is provided whose 90 ° angle or its 90 ° bend has good electrical transmission properties including the cross-polarization decoupling for both polarizations.

For the implementation of such 90 ° waveguide has already been proposed to form the transition as a continuous arc section (in side view so as part-circular rectangular tube).

However, the most common embodiment is that the two mutually perpendicular waveguide sections are connected in the 90 ° -Krümmerbereich so that the internal 90 ° corner point outside connecting side is an edge length of a √2, where a is the edge length of the square waveguide. The length of the bend thus corresponds to a diagonal in a square with the edge length a.

According to the invention, a deviating geometry is proposed, in which the chamfer of the compensated corner in the 90 ° bend region corresponds to the edge length a of a square waveguide, wherein slight deviations of less than 0.1% can still be regarded as sufficient in the sense of the invention.

In the dimension rule mentioned above, the inner dimension of the waveguide must always be taken into account, and not the outer lengths, taking into account the wall thicknesses. In this case, the square waveguide on its connecting pieces as a light internal dimension, the edge length a. So should also have the beveled wall in the angular range as an inner measure a length in the propagation direction of the electromagnetic waves, which corresponds to the dimension a of the clear distance to the square in cross-section fittings.

Even if the invention speaks of a 90 ° elbow, this elbow does not necessarily have to have an extant 90 °. In principle, it can also be a manifold which is designed for an angular range between 70 ° to 110 °, especially for an angular range between 80 ° and 100 ° or in particular for an angular range between 85 ° to 95 °.

It is basically a 90 ° -Hohlleiterkrümmer also from the US 6,253,444 B1 known. In difference However, the subject of the invention is not a square in cross-section, but a rectangular in cross section waveguide manifold. In addition, it is found essential according to this prior publication that the waveguide manifold in the transition region has no bevel comparable to the present invention, but that here stepped heels are incorporated into the waveguide material. These may be a few large-sized steps or a plurality of steps, which are formed according to the number of stages with a smaller step height. In the context of the invention, however, it has been shown that such an embodiment does not lead to the desired properties, as can be realized within the scope of the invention.

Figur 1:

eine schematische räumliche Darstellung des erfindungsgemäßen 90°-Hohlleiterkrümmers; und

Figur 2 :

eine schematische Seitenansicht auf das Ausführungsbeispiel gemäß Figur 1.

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

FIG. 1:

a schematic spatial representation of the inventive 90 ° -Hohlleiterkrümmers; and

FIG. 2:

a schematic side view of the embodiment of Figure 1.

FIG. 1 shows, in a schematic 3D representation, an exemplary embodiment of a 90 ° waveguide manifold according to the invention, which comprises two mutually perpendicular, straight waveguide connecting pieces 1.

These waveguide connecting pieces 1 have a square cross-section, with an edge length a.

The housing wall is made of electrically conductive material, in particular of metal. This is preferably a cast material, since the waveguide according to the invention is to be produced in a casting process. Preferably, zinc, brass and / or aluminum is used as cast or die cast materials. Other materials or combinations of materials and alloys are also conceivable. The waveguide angle according to the invention does not necessarily have to be produced in a casting process. Other manufacturing methods and methods are possible.

For the sake of completeness, it is mentioned that, in principle, a waveguide material made of nonconductive, dielectric material may also be considered if it is coated with an electrically conductive layer. As a rule, the waveguide connecting pieces 1 at their end face open connection side 3 nor a circumferential flange, to which the waveguide manifold thus formed with a subsequent, usually straight waveguide connector or, for example, a waveguide terminal of an LNB or other components are connected can.

If the ends of a waveguide bend are usually equipped with flanges, then so-called screw flanges in particular come into consideration, as are customary with rectangular waveguides. Likewise, it is possible to connect the described waveguide manifold, for example, to an LNB by means of a muff connection. This means that the waveguide elbow over the waveguide port of the LNB's inverts or over. The other end of the waveguide manifold may be equipped so that Depending on the subsequent component a corresponding connection can be ensured.

As can be seen from the 3D representation according to FIG. 1, the 90 ° waveguide bend or waveguide angle has an inner edge 5 on which the inner wall sections 7 of the two waveguide connecting pieces 1 converge at a 90 ° angle. In other words, the left in Figure 1 inner wall portion 7 and also belonging to the left waveguide connector 1 outer wall portion 9 are parallel to each other. Likewise, the inner and the outer wall portion 7, 9 of the right in Fig. 1 lying waveguide connection piece 1 are aligned parallel to each other. The inner and outer wall portion 7, 9 of the left-lying waveguide connecting piece 1 are then aligned perpendicular to the inner and outer wall portions 7, 9 of the right in Figure 1 waveguide connector 1.

The respective upper and lower wall sections 11 of the two waveguide connecting pieces 1, which are offset by 90.degree. From the mentioned wall sections 7 and 9, lie in a common plane, namely in a lower plane shown in FIG also the manifold boundary wall 15 of the actual angle section 17 comes to rest. Both in the plane lying at the top in FIG. 1 and at the bottom in FIG. 1, the manifold boundary wall 15 constitutes a transition wall section between the wall sections 11 of the two waveguide connecting pieces 1. from the wall portion 11, the adjacent manifold boundary wall 15 and the next Wall portion 11 of the next waveguide connector 1 plane formed (as well as all parallel planes to) the so-called curvature plane in which the 90 ° bend and the propagation direction of the waveguide is defined).

As can be seen in particular from the top view according to FIG. 2, a chamfer 19, which is perpendicular and symmetrical to the bisector 21 of the 90 °, is provided on the inside 90 ° edge 5, which runs perpendicular to the plane of the drawing in plan view according to FIG Smash runs.

According to this arrangement, thus resulting balancing wall sections 23 which come to lie in each case in extension of the outer wall portion 9 of the two waveguide fittings 1 in the same plane with these.

The chamfer 19 has in plan view according to FIG. 2 a length which corresponds to the edge length a of the waveguide connecting pieces 1, which are square in cross-section. Such dimensioning provides the best transmission conditions for the propagation of an electromagnetic wave in this waveguide elbow. Deviations from the edge length a for the chamfer 19 in the propagation direction of the electromagnetic waves of less than 0.5% are still sufficient to achieve the desired result.

The length of the designated as bevel 19 and preferably in a 135 'angle to the alignment of the waveguide connecting pieces 1 extending wall (ie in the direction of propagation of the waveguide manifold extending electromagnetic waves) corresponds to the edge length a, that is to say has the same length as the edge length at the opening region of the waveguide connecting pieces 1. This length of the chamfer 19 is thus measured in the direction of the plane of curvature. Since the height in the direction perpendicular thereto in the waveguide manifold likewise has the edge length a, the wall defined by the bevel 19 thus has a square shape, since not only the length but also the height perpendicular thereto corresponds to the edge length a.

The invention has been described with reference to a 90 ° -Hohlleiterkrümmers. However, the waveguide curvature can also have other values and is not necessarily limited to 90 °. In principle, the waveguide manifold could have a curvature between 80 ° to 100 ° or less, for example between 85 ° and 95 ° or between 87 ° and 93 °, in particular between 89 ° and 91 °. In that regard, a 90 ° -Hohlleiterkrümmer in the context of the invention, a manifold understood that has one of the above-mentioned angle ranges.

It should also be noted that the dimensions given above with regard to the edge length with the dimension a as well as with respect to the length of the bevel with the length a in each case relate to the internal dimension of the waveguide sections. In deviation from this, the waveguide elbow can have an arbitrarily thick wall with an arbitrarily thick wall thickness, so that the outer dimension at the edge length or the outer dimension at the bevel can deviate from the length a. The waveguide inner dimension with respect to the square opening has with respect to the waveguide channel in the longitudinal and transverse directions of the square Waveguide an edge length a, wherein the inside of the waveguide inner piece measure of the chamfer has the length a and a height with the clear inner dimension a.

Therefore, the outer contours can also be angular in the area of the so-called bevel. In other words, the compensating wall sections 23 shown in the figures can be made longer and terminate at right angles to one another with the formation of an outer vertical edge, as if no bevelled wall 19 were provided internally as the boundary wall of the waveguide channel. Because as stated, only the measurement and the design of the waveguide elbow with respect to the waveguide channel limiting inner walls is crucial. In other words, all of the walls explained above represent the inner walls and / or surfaces that bound the waveguide channel to the outside.

Claims (8)

90 ° waveguide header with the following features: the waveguide manifold has two mutually perpendicular waveguide connecting pieces (1), the waveguide connecting pieces (1) have a square inner cross section with an edge length (a), between the two waveguide connecting pieces (1) is provided an angle section (17) which produces the 90 ° change in direction, - The angle section (17) has outboard to the 90 ° direction change on a chamfer (19) as a boundary wall for the waveguide, wherein by the bevel (19) of the waveguide channel is limited to the outside,
characterized by the following further features: - The chamfer (19) has in the plane of curvature of a length which corresponds to the edge length (a) of the square in cross-section waveguide fittings (1), ± less than 0.5%. 90 ° waveguide according to claim 1, characterized in that by the bevel (19) defined Boundary wall of the waveguide manifold is square. 90 ° waveguide according to claim 1, characterized in that the chamfer (19) is aligned perpendicular to the bisector (25) of the 90 ° -Hohlleiterkrümmers. 90 ° waveguide according to one of claims 1 to 3, characterized in that the chamfer (19) is perpendicular to an inner edge (5), at the inside of the 90 ° -Krümmer the two waveguide fittings (1) with their inside wall sections (7) abut each other. 90 ° waveguide according to one of claims 1 to 4, characterized in that the chamfer (19) merges into two outer compensating wall sections (23), each in extension of the respective outer wall portion (9) of the two waveguide connecting pieces (1 ) lie. 90 ° waveguide according to one of claims 1 to 5, characterized in that the length of the inner and the outer wall sections (7, 9) in the direction of propagation of the electromagnetic waves at the connecting pieces (1) is preselected and / or variable. 90 ° -Hohlleiterkrümmer according to one of claims 1 to 6, characterized in that the waveguide manifold is formed so that it allows a propagation of an electromagnetic wave in an angular range of 85 ° to 100 °, preferably 85 ° to 95 °. 90 ° waveguide according to any one of claims 1 to 7, characterized in that the waveguide manifold is formed as a metal casting.

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