EP1881551B1 - Wave guide manifold - Google Patents

Description

The invention relates to a 90 ° -Hohlleiterkrümmer.

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. In most cases, these are 90 ° elbows, where the direction of the electric field lines (E-bend, E-angle), that is the rectangular waveguide over the broadside, or the direction of the magnetic field lines (H-bend, H- Angle), ie with 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-A1-0 285 295 known. The square in cross-section 90 ° -Hohlleiterkrümmer has an edge length according to an embodiment FIG. 2 of this prior publication, which is given as 0.900 inch (1 inch equals 25.4 mm). To optimize the waveguide bulk while reducing the attenuation, the length L is from the beginning of the taper to the extreme 90 ° corner point in the case of optimizing the E-plane waves 0.700 inches and for optimizing the H-plane wave 0.642 Inch should be at an edge length of the waveguide cross section of 0.900 inches. In the latter case, the chamfer points in the propagation direction the electromagnetic waves have a length that exceeds the edge length by almost 1%.

A 90 ° -Hohlleiterkrümmer is basically from the US-A 2 411 338 known. A in cross-section rectangular waveguide manifold is also the EP-A1-0 012 978 to be known as known.

Finally, a Hohlleiterkrümmer with square inner cross section and from the JP 03 167901 A known. This prior publication describes different embodiments with a circular waveguide manifold and an angularly extending waveguide manifold.

In contrast, it is an object of the present invention, starting from the generic state of the art to provide a waveguide with a 90 ° -Hohlleiterkrümmer, ie a 90 ° waveguide angle, which should be easier and cheaper to produce, at the same time good electrical transmission properties in terms of Propagation of the electromagnetic waves (ie both the E and the H-plane waves) to be achieved in the waveguide.

The object is achieved according to the features specified in claim 1. An advantageous embodiment of the invention is specified in the dependent claim.

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

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 common practice 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 are necessary, i. a space-saving 90 ° -Knick is not feasible.

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

For the specified frequency range, the edge length is e.g. 15 mm.

It is surprising that in the context of the invention, a waveguide manifold is created whose 90 ° angle for both polarizations good electrical transmission properties including the cross-polarization decoupling.

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 waveguide sections formed perpendicular to each other in the 90 ° bend region are connected such that the connecting side located at the inner 90 ° corner point 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 bevel of the compensated corner in the 90 ° bend region has the edge length a of the square waveguide, wherein slight deviations of less than 0.1% can still be considered sufficient in the sense of the invention. In this case, the inventive 90 ° -Hohlleiterkrümmer is made of zinc die-cast material.

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 the beveled wall in the angular range as Innenmaß a length in the propagation direction have the electromagnetic waves, which is equal to the dimension a of the clear distance at the square in cross-section Anschlusstücken.

It is basically a 90 ° -Hohlleiterkrümmer also from the US 6,253,444 B1 known. In contrast to the subject invention, this 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 comparable with the present invention bevel, 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 according to FIG. 1 ,

In FIG. 1 is a schematic 3D representation of an inventive embodiment of a 90 ° -Hohlleiterkrümmers shown comprising two mutually perpendicular, straight-running waveguide fittings 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, namely metal. It is a cast material, since the waveguide according to the invention is to be produced in a casting process. For this purpose, zinc is used as cast or die cast material.

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 can be so equipped be that depending on the subsequent component, a corresponding connection can be ensured.

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

The respective upper and lower wall sections 11 of the two waveguide connecting pieces 1, which are each offset by 90.degree. From the mentioned wall sections 7 and 9, lie in one common plane, namely in one FIG. 1 shown upper and a parallel lower plane in which also the manifold boundary wall 15 of the actual angle section 17 comes to rest. Both in the in FIG. 1 overhead level as well as in the FIG. 1 Below level, the manifold boundary wall 15 is a transition wall portion respectively between the wall portions 11 of the two waveguide fittings 1.

As can be seen in particular from the top view FIG. 2 results is to the inner 90 ° edge 5, which in plan view according to FIG. 2 extends perpendicular to the plane, outboard a bevel 19 provided as a boundary wall which is perpendicular and symmetrical to the bisector 21 of the 90 ° -Krümmers.

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 is equal to the edge length a of the square in cross-section waveguide fittings 1. 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 0.1% are still sufficient to achieve the desired result.

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

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 may have an arbitrarily thick wall with an arbitrarily thick wall thickness, so that the outer dimensions of the edge length or the outer dimension of the bevel of the length a may differ. The waveguide internal dimension with respect to the square opening has an edge length a with respect to the waveguide channel in the longitudinal and transverse directions of the square waveguide, wherein the internal dimension of the chamfer in the waveguide inner piece has the length a and a height with the clear internal dimension a.

Therefore, also in the area of the so-called bevel, the outer contours can be angular. 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 is with respect to the waveguide channel limiting inner walls 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 (2)

1. 90° waveguide bend having the following features:

   - the waveguide bend has two waveguide connectors (1) that are perpendicular to each other,

   - an angular portion (17) producing the 90° change in direction is provided between the two waveguide connectors (1);

   - externally to the 90° change in direction, the angular portion (17) has a quadratic chamfer (19) and respective compensating wall portions (23) as a delimiting wall for the waveguide bend, by means of which the waveguide channel is outwardly delimited;

   - the waveguide connectors (1) have a quadratic internal cross section having an edge length a;

   - the side length of the chamfer (19) is equal to the edge length a having a deviation of less than ± 0.1 %;

   - the chamfer (19) is oriented perpendicularly to the bisecting line (21) of the 90° waveguide bend;

   - the 90° waveguide bend is designed for transmitting a frequency range of from 10.7 GHz to 12.75 GHz; and

   - the 90° waveguide bend consists of a zinc diecasting material.
2. 90° waveguide bend according to claim 1, wherein the length of the internal and external wall portions (7, 9) of the waveguide connectors (1) is preselectable in the direction of propagation of the electromagnetic waves.

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