EP1168480A1 - Transition for orthogonally oriented hollow waveguides - Google Patents

Abstract

The invention relates to a transition for orthogonally oriented waveguides (H1, H2), with a transformation stage (T), a first elongated opening for connecting a first waveguide (H1), which is designed for guiding a first type of basic wave (H10), and a has a second elongated opening for connecting a second waveguide (H2), which is designed for guiding a second basic wave type (H01), the first elongated opening and the second elongated opening being aligned orthogonally to one another. It is provided according to the invention that the transformation stage (T) has an essentially rectangular geometry with a height (h), a width (b) and a depth (t), the height (h) and the width (b) being chosen in this way that both the first basic wave type (H10) and the second basic wave type (H01) can be propagated in the transformation stage (T). <IMAGE>

Description

The present invention relates to a transition for orthogonally oriented waveguides, with a transformation stage which has a first elongated opening for connecting a first waveguide, which is designed for guiding a first basic wave type, and a second elongated opening for connecting a second waveguide, for guiding of a second basic wave type, wherein the first elongated opening and the second elongated opening are aligned orthogonally to one another.

State of the art

The known generic transitions are realized, for example, by a combination of several waveguide sections which are twisted relative to one another. A description of such a transition can be found, for example, in the "Taschenbuch der Hochfrequenztechnik, Meinke / Grundlach, 2nd edition, pages 399 ff.". However, the production of such a transition from several waveguide sections is very complex and a further problem is that such transitions cannot be used in so-called integrated waveguide circuits, which are realized by the half-shell technology.

Another generic transition, which could in principle be produced by half-shell technology, is known from EP 0392999B1. This document relates to a field-rotating waveguide transition in waveguides for electromagnetic microwaves, the transition at one end having a rectangular-like cross-sectional shape with the desired height and width, the cross-sectional shape differing from a rectangular shape by a web which in the transition from one side of the cross-section protrudes in the height direction of the cross-section, and the transition has a rectangular cross-sectional shape with a long side and a short side at its other end. According to EP 0392999B1 it is provided that the waveguide transition has a first part which extends from one end of the rectangular-like cross section to a central section with an L-shaped cross section and a second part which extends from the central section to the other end of the rectangular cross section; that the height extension of the inwardly projecting web at one end of the waveguide transition has essentially the same direction as the long side of the rectangular cross section at the other end of the waveguide transition; and that the L-shaped central section on one side of the web has a smaller extent than the rectangular-like cross section and on the other side of the web has a corresponding extent greater than has the rectangular-like cross section in the height direction of the inwardly projecting web. The transition according to EP 0392999B1 is also composed of several waveguide sections with different cross-sectional geometries. However, the production of this transition is complex and the required overall length is relatively large, which is disadvantageous in particular in connection with integrated waveguide circuits.

Advantages of the invention

The fact that in the transition according to the invention it is provided that the transformation stage has a substantially rectangular geometry with a height, a width and a depth, the height and the width being selected such that both the first basic wave type and the second basic wave type in FIG the transformation stage are spreadable, a compact, easily manufactured transition with a comparatively short overall length is created, which adapts the fundamental wave types of two orthogonally oriented waveguides with little reflection over a wide frequency range. The structure according to the invention results in a hybrid wave type in the transformation stage, by means of which a transformation between the first basic wave type and the second basic wave type is achieved. The transition according to the invention can, for example, be integrated as a component in planar waveguide circuits. Due to the polarization rotation within an overall structure that is possible with the transition according to the invention, the optimal installation position can be achieved with complex integrated waveguide circuits or coupling for each component can be achieved. Despite the short overall length possible with the transition according to the invention, very good electrical properties are achieved over a very wide frequency range. Furthermore, due to the possible very short overall length in the case of complex integrated waveguide circuits, for example in the distribution networks for array antennas described in the aforementioned EP 0392999B1, in which several of the generic transitions are required, a very compact overall construction can be achieved.

It is preferably provided that the transformation stage has a length or depth ((2n + 1) λ / 4, with n = 0.1, 2, 3 ..., where λ is the waveguide wavelength of the H10 or H01 wave type in the range is the transformation level. Such a length or depth of the transition according to the invention enables optimal energy transport, the shortest and preferred possible length or depth being approximately λ / 4. In particular if the width and the height of the transformation stage have similar dimensions, the corresponding limit wavelengths λ _iH01 and λ _iH10 and thus the waveguide wavelengths of the wave types H10 and H01 are similar in the region of the transformation stage. The following then applies to the length of the transformation stage with λ _H01 ≈ λ _H10 : t ≤ (λ _H10 + λ _H01 ) / 8 ≈ λ _H10 / 4 ≈ λ _H01 / 4. Furthermore, λ can be the mean waveguide wavelength of the useful frequency band of the first and second waveguides.

The first elongated opening is preferably arranged in the front end face of the transformation stage, and the second elongated opening is preferably arranged in the rear end face of the transformation stage.

The first elongated opening can be arranged horizontally in the upper or lower region of the front face of the transformation stage.

The length of the first elongated opening may be approximately the width of the transformation step in certain embodiments. This is particularly useful if the first waveguide is connected directly to the transformation stage, that is to say without an interposed aperture and without a further transformation stage.

The second elongated opening is preferably arranged vertically in the left or right region of the rear end face of the transformation stage. Particularly when the second elongated opening is located immediately adjacent to the left or right edge of the rear face of the transformation stage, good results are achieved.

The length of the second elongated opening may be approximately the height of the transformation step in certain embodiments. This solution in turn is appropriate if the second waveguide is connected directly to the transformation stage, that is to say without an interposed aperture and without a further transformation stage.

In order to increase the bandwidth, it can be provided in certain embodiments of the transition according to the invention that the first opening is connected to a further transformation stage which is provided for connecting the first waveguide.

In this case, the further transformation stage can be arranged symmetrically to the cross section of the first waveguide and asymmetrically to the transformation stage. However, embodiments are also conceivable in which the further transformation stage is arranged with a different symmetry or asymmetrically depending on the overall structure.

If a further transformation level is used, its width may be smaller than that of the transformation level.

Of course, it is also conceivable that a further transformation stage is also or only assigned to the second opening.

Furthermore, it is conceivable that the first opening is connected to a first diaphragm, which is provided for connecting the first waveguide. This first aperture can also increase the bandwidth of the transition.

Although this is not absolutely necessary, the width of the first aperture can be smaller than the width of the Transformation stage, depending on the desired transmission behavior.

To further increase the bandwidth, the second opening can be connected to a second aperture, which is provided for connecting the second waveguide.

The width of the second aperture can then be smaller than the height of the transformation stage.

Since the transition according to the invention can be implemented by the half-shell technique, it can be produced in a simple manner, for example by a milling process.

Furthermore, the transition according to the invention can be formed by an integrated waveguide circuit or can be part of such an integrated waveguide circuit.

The first waveguide and the second waveguide can optionally have different cross-sectional dimensions. For example, a standard waveguide (width: height ≈ 1: 2) could be connected on one side and a waveguide with a reduced width (width: height ≈ 1: 4) could be connected on the other side. In this context, it is also conceivable that the first and the second waveguide are formed by two different standard waveguides with different fundamental wavelengths. The cross section of the waveguide does not have to be exactly rectangular, but it can also be rounded Rectangular geometries or elliptical waveguides can be used.

Due to the asymmetrical arrangement of the waveguides common to the various embodiments, a hybrid wave type is created in the transformation stage, through which the transformation takes place.

drawings

The invention is explained below with reference to the accompanying drawings.

• Figur 1 eine erste Ausführungsform des erfindungsgemäßen Übergangs;
• Figur 2 eine zweite Ausführungsform des erfindungsgemäßen Übergangs;
• Figur 3 eine dritte Ausführungsform des erfindungsgemäßen Übergangs;
• Figur 4 eine Draufsicht auf den Übergang gemäß Figur 3;
• Figur 5 eine Seitenansicht des Übergangs gemäß Figur 3;
• Figur 6 ein magnetisches Feldbild in dem Übergang gemäß Figur 3 an einer ersten Schnittebene;
• Figur 7 ein magnetisches Feldbild in dem Übergang gemäß Figur 3 an einer zweiten Schnittebene; und
• Figur 8 ein magnetisches Feldbild in dem Übergang gemäß Figur 3 an einer dritten Schnittebene.

Show it:

• Figure 1 shows a first embodiment of the transition according to the invention;
• Figure 2 shows a second embodiment of the transition according to the invention;
• Figure 3 shows a third embodiment of the transition according to the invention;
• FIG. 4 shows a top view of the transition according to FIG. 3;
• FIG. 5 shows a side view of the transition according to FIG. 3;
• FIG. 6 shows a magnetic field image in the transition according to FIG. 3 on a first sectional plane;
• FIG. 7 shows a magnetic field image in the transition according to FIG. 3 on a second sectional plane; and
• FIG. 8 shows a magnetic field image in the transition according to FIG. 3 on a third sectional plane.

Description of the embodiments

FIG. 1 shows a one-stage embodiment of a transition for orthogonally oriented waveguides H1, H2. The transition comprises a transformation stage T, which has an essentially rectangular geometry. The height of the transformation stage T is designated with h, the width with b and the depth with t. The transformation stage T has a first elongated opening for connecting a first waveguide H1, which is designed for guiding a first basic wave type H10. The height h and the width b of the transformation stage T are chosen such that both the first basic wave type H10 and the second basic wave type H01 can spread in the transformation stage T. The length or depth t of the transformation stage T is selected in the illustrated case such that the relationship t ((2n + 1) λ / 4, with n = 0.1, 2, 3, ..., is fulfilled. λ is the waveguide wavelength of the H10 or H01 wave type in the region of the transformation stage T, preferably the mean waveguide wavelength of the useful frequency band. As shown in FIG. 1, the first elongated opening is arranged in the lower region of the front end face S1 of the transformation stage T, and the length 11 of the first elongated opening corresponds to the width b of the transformation stage T. The second elongated opening is arranged in the right area of the rear end face S2 of the transformation stage T, and the length 12 of the second elongated opening corresponds to the height h of the transformation stage T. This asymmetrical arrangement of the first elongated opening and the second elongated opening or the first waveguide H1 and the second waveguide H2, a hybrid wave type is created in the transformation stage T, by means of which the transformation takes place.

FIG. 2 shows a second two-stage embodiment of the transition according to the invention. The transformation stage T has a first elongated opening for connecting a first waveguide H1, which is designed for guiding a first basic wave type H10. The basic direction of polarization of the first basic wave type H10 is indicated in FIG. 2 by the corresponding arrow. Furthermore, the transformation stage T has a second elongated opening for connecting a second waveguide H2, which is designed for guiding a second basic wave type H01. The basic polarization of the second basic wave type H01 is also indicated in FIG. 2 by a corresponding arrow. The height h and the width b of the transformation stage T are selected such that both the first basic wave type H10 and the second basic wave type H01 can be propagated in the transformation stage T. The length or depth t of the transformation stage T is preferably chosen such that the relationship t ((2n + 1) λ / 4, with n = 0.1, 2, 3,..., Is fulfilled, where λ is the waveguide wavelength of the H10 - or the H01 shaft type in the range of the transformation stage T, preferably the mean waveguide wavelength of the useful frequency band. The first elongated opening is arranged in the lower region of the front end face S1 of the transformation stage T, the width of the first opening being somewhat smaller in this embodiment than the width b of the transformation stage T. The second elongated opening is arranged in the right region of the rear end face S2 of the transformation stage T, the length of the second elongated opening corresponding to the height h of the transformation stage T in the embodiment shown in FIG. The first elongated opening and the second elongated opening are thus aligned orthogonally to one another. In order to increase the bandwidth of the transition compared to the embodiment shown in FIG. 1, the first waveguide H1 is not directly connected to the first elongated opening, but via a further transformation stage T10. In the case shown, the width of the further transformation stage T10 corresponds to the width of the first elongated opening, that is to say it is somewhat smaller than the width b of the transformation stage T.

Although this is not shown, embodiments are conceivable in which only or also the second waveguide H2 is connected to the second elongated opening via a corresponding further transformation stage.

FIGS. 3 to 5 show a third three-stage embodiment of the transition according to the invention, wherein FIG. 3 shows a perspective schematic illustration, FIG. 4 shows a top view and FIG. 5 shows a side view of the third embodiment of the transition. The transformation stage T has a first elongated opening for connecting a first waveguide H1, which is designed for guiding a first basic wave type H10. The basic direction of polarization of this first basic wave type H10 is indicated in FIG. 3 by a corresponding arrow. Furthermore, the transformation stage T has a second elongated opening for connecting a second waveguide H2, which is designed for guiding a second basic wave type H01. The basic direction of polarization of the second basic wave type H01 is also indicated in FIG. 3 by a corresponding arrow. In this embodiment too, the transformation stage T has an essentially rectangular geometry with a height h, a width b and a depth t. The height h and the width b are chosen such that both the first basic wave type H10 and the second basic wave type H01 can be propagated in the transformation stage T. The length or depth t of the transformation stage T is selected such that it fulfills the relationship t Beziehung (2n + 1) λ / 4, with n = 0.1, 2, 3, ..., where λ is the waveguide wavelength of the H10 or of the H01 wave type in the region of the transformation stage T, preferably the mean waveguide wavelength of the useful frequency band. As can be seen in FIG. 3, the first elongated opening of the transformation stage T is arranged in the lower region of the front end face S1 of the transformation stage T. The second elongated opening is arranged in the right area of the rear end face S2 of the transformation stage T. The first elongated opening and the second elongated opening are thus aligned orthogonally to one another. Compared to the bandwidth of the transition according to the invention To increase the embodiment according to FIG. 1, the first waveguide H1 in the embodiment shown in FIGS. 3 to 5 is not directly connected to the first elongated opening in the front end face of the transformation stage T, but a first aperture B1 is provided, via which the first waveguide H1 communicates with the first elongated opening. As can be seen from FIGS. 3 and 4, the width of the first opening and the first diaphragm B1 is selected in this embodiment in such a way that it is somewhat smaller than the width b of the transformation stage T. In this embodiment, the second waveguide H2 is also not directly connected to the second elongated opening in the right region of the rear end face S2 of the transformation stage T, but a second diaphragm B2, which is connected to the second elongated opening, connects the second waveguide H2 to the second elongated opening. As can be seen in particular from FIGS. 3 and 4, the width of the second elongated opening and the width of the second diaphragm B2 are selected such that they are somewhat less than the height h of the transformation stage T. In contrast to the connection method of the first waveguide H1, the second waveguide H2 is connected asymmetrically with respect to the second aperture B2 in this embodiment, although this is not absolutely necessary. In relation to the third embodiment shown in FIGS. 3 to 5, it can be summarized that the first diaphragm B1 and the second diaphragm B2 are arranged asymmetrically at the transformation stage T, in such a way that the first diaphragm B1 is located on the lower edge of the front end face S1 and the second panel B2 on the right Edge of the rear end face S2 are arranged. The length of the waveguide section T is somewhat shorter than λ / 4 of the mean waveguide wavelength of the useful frequency band in the case shown. This structure of the transition creates a hybrid wave type in the transformation stage T, through which the transformation between the orthogonal H10 and H01 wave types is achieved. The embodiment shown in FIGS. 3 to 5 enables a reflection characteristic with a Chebyshev curve to be achieved, which has three zeros, in order to thus realize the correspondingly large useful bandwidth. The asymmetry of the first aperture B1 with respect to the height h and that of the second aperture B2 with respect to the width b of the transformation stage T is essential for the function of the transition. An asymmetry in the respective other cross-sectional dimension is possible, as shown for example for the second aperture B2 is, but not required. As already mentioned, the asymmetry of the second diaphragm B2 shown with respect to the second waveguide H2 is also not absolutely necessary.

FIGS. 6 to 8 show magnetic field images which occur at different sectional planes of the third embodiment of the transition according to the invention shown in FIGS. 3 to 5. The magnetic field image shown in FIG. 6 arises in the plane ZX shown in FIG. 5. The magnetic field image shown in FIG. 7 is set along the plane ZY shown in FIG. 4 and the magnetic field image shown in FIG. 8 is set up in the plane XY, which is shown both in FIG. 4 and in FIG. 5. In Figures 6 to 8, the field rotation achieved by the hybrid wave type generated in the transformation stage T can be clearly seen.

The three illustrated embodiments have in common that they can be integrated in planar waveguide circuits and can be produced, for example, by milling technology. Despite the short overall lengths, as mentioned, very good electrical properties are achieved over a very wide frequency range.

The features of the invention disclosed in the above description, in the drawings and in the claims can be essential for realizing the invention both individually and in any combination.

Claims (17)

Transition for orthogonally oriented waveguide (H1, H2), with a transformation stage (T), which has a first elongated opening for connecting a first waveguide (H1), which is designed to guide a first type of fundamental wave (H10), and a second elongated opening for Connection of a second waveguide (H2), which is designed to conduct a second basic wave type (H01), wherein the first elongated opening and the second elongated opening are oriented orthogonally to one another, characterized in that the transformation stage (T) has a substantially rectangular geometry with a height (h), a width (b) and a depth (t), the height (h) and the width (b) being selected such that both the first basic wave type (H10) and the second basic wave type ( H01) is spreadable in the transformation stage (T). Transition according to claim 1, characterized in that the transformation stage (T) has a length or depth (t) ≤ (2n + 1) λ / 4, with n = 0,1,2,3 ..., where λ the waveguide wavelength of the first basic wave type (H10) or the second basic wave type (H01) is in the region of the transformation stage (T). Transition according to one of the preceding claims, characterized in that the first elongated opening is arranged in the front end face (S1) of the transformation stage (T), and in that the second elongated opening is arranged in the rear end face (S2) of the transformation stage (T) , Transition according to one of the preceding claims, characterized in that the first elongated opening is arranged horizontally in the upper or lower region of the front end face (S1) of the transformation stage (T). Transition according to one of the preceding claims, characterized in that the length (11) of the first elongated opening approximately corresponds to the width (b) of the transformation step (T). Transition according to one of the preceding claims, characterized in that the second elongated opening is arranged vertically in the left or right region of the rear end face (S2) of the transformation stage (T). Transition according to one of the preceding claims, characterized in that the length (12) of the second elongated opening corresponds approximately to the height (h) of the transformation step (T). Transition according to one of the preceding claims, characterized in that the first opening with a is connected to another transformation stage (T10), which is provided for connecting the first waveguide (H1). Transition according to one of the preceding claims, characterized in that the further transformation stage (T10) is arranged symmetrically to the cross section of the first waveguide (H1) and asymmetrically to the transformation stage (T). Transition according to one of the preceding claims, characterized in that the width of the further transformation stage (T10) is smaller than the width (b) of the transformation stage (T). Transition according to one of the preceding claims, characterized in that the first opening is connected to a first aperture (B1) which is provided for connecting the first waveguide (H1). Transition according to one of the preceding claims, characterized in that the width of the first aperture (B1) is smaller than the width (b) of the transformation stage (T). Transition according to one of the preceding claims, characterized in that the second opening is connected to a second aperture (B2) which is provided for connecting the second waveguide (H2). Transition according to one of the preceding claims, characterized in that the width of the second aperture (B2) is less than the height (h) of the transformation stage (T). Transition according to one of the preceding claims, characterized in that it is produced by a milling process. Transition according to one of the preceding claims, characterized in that it is formed by an integrated waveguide circuit or is part of this. Transition according to one of the preceding claims, characterized in that the first waveguide (H1) and the second waveguide (H2) have different cross-sectional geometries.

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