POLARISATION-PRESERVING FILTER FOR A DUAL-POLARISED WAVEGUIDE

Abstract

A polarisation-preserving filter for a dual-polarised waveguide with a basic body that is circular in cross section. Arranged in the interior of the basic body is a plurality of nubs, wherein the nubs are grouped in several rings, due to which a first, predetermined frequency band can be transmitted unobstructed and the transmission of a second, predetermined frequency band can be blocked.

Claims

1. A polarisation-preserving filter for a dual-polarised waveguide with a basic body that is circular in cross section, the filter comprising a plurality of nubs arranged in an interior of the basic body, wherein the nubs are grouped in several rings, wherein a first predetermined frequency band can be transmitted unobstructed and transmission of a second predetermined frequency band can be blocked.

2. The filter of claim 1, wherein the nubs have one or more of the following structural forms: cuboid; cylinder; hemisphere; hemiellipsoid; prism; cone or truncated cone; pyramid or truncated pyramid; combinations of different geometries.

3. The filter of claim 1, wherein the number of nubs per ring is identical.

4. The filter of claim 3, wherein adjacent nubs of the rings are arranged on an axis parallel to the direction of the axial extension of the basic body.

5. The filter of claim 1, wherein the number of nubs per ring is different.

6. The filter of claim 1, wherein the dimensions of the nubs of a ring are identical in respect of at least one of height and lateral extension.

7. The filter of claim 1, wherein the dimensions of the nubs of a ring are different in respect of at least one of height and lateral extension.

8. The filter of claim 1, wherein the nubs are distributed evenly over the circumference of a ring.

9. The filter of claim 1, wherein the nubs are distributed differently over the circumference of a ring, so that the spacings between two nubs have different values.

10. The filter of claim 1, wherein the spacings of the rings are identical in an axial direction of the basic body.

11. The filter of claim 1, wherein the spacings of the rings are different in an axial direction of the basic body.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The various embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and:

[0022] FIG. 1 shows a representation in perspective of a first configuration variant of a dual-polarised waveguide with a polarisation-preserving filter according to an embodiment of the invention;

[0023] FIG. 2 shows a front view of the waveguide from FIG. 1;

[0024] FIG. 3 shows a representation in perspective of a dual-polarised waveguide with a polarisation-preserving filter according to a second configuration variant;

[0025] FIG. 4 shows a lateral view of the waveguide from FIG. 3, wherein the arrangement of the nubs of the polarisation-preserving filter is visible to illustrate the construction of the polarisation-preserving filter;

[0026] FIG. 5 shows a front view of the waveguide from FIG. 3 with spherical nubs;

[0027] FIG. 6 shows a front view of a waveguide with lengthwise elliptical nubs of a polarisation-preserving filter according to an embodiment of the invention;

[0028] FIG. 7 shows a front view of a waveguide with cone-shaped nubs of a polarisation-preserving filter according to an embodiment of the invention;

[0029] FIG. 8 shows a front view of a waveguide with tetrahedron-shaped nubs of a polarisation-preserving filter according to an embodiment of the invention; and

[0030] FIG. 9 shows a front view of a waveguide with prism-shaped nubs of a polarisation-preserving filter according to an embodiment of the invention.

DETAILED DESCRIPTION

[0031] The following detailed description is merely exemplary in nature and is not intended to limit the disclosed embodiments or the application and uses thereof. Furthermore, there is no intention to be bound by any theory presented in the preceding background detailed description.

[0032] FIG. 1 shows in a representation in perspective a dual-polarised waveguide 1 with a basic body that is circular in cross section, i.e. cylindrical. In the interior of the basic body 2, a polarisation-preserving filter is arranged, which comprises a number of nubs 3, which are arranged in several rings 4 arranged coaxially with reference to a longitudinal axis 5. By way of example the nubs 3 in the polarisation-preserving filter shown in FIG. 1 have the form of a square.

[0033] As is evident from the front view in FIG. 2, for example, which shows the waveguide from the front, eight nubs 3 are arranged by way of example in a ring 4 and distributed evenly over the circumference of the ring 4. The nubs 3 are formed identically in this case with regard to their spatial dimensions in relation to an axial extension as well as a radial extension. In the variant illustrated in FIG. 2, it is further provided that the adjacent nubs 3 of adjacent rings 4 are arranged in one axis in each case, wherein the eight axes run parallel to the direction of the axial extension of the basic body 2.

[0034] In this as in all other practical examples, the nubs 3 extend from the circular wall of the basic body 2 in the direction of the centre of the cylindrical basic body 2. In the configuration variant shown in FIGS. 1 and 2, the nubs 3 are arranged in such a way that these lie opposite one another in pairs. Adjacent nubs are thus offset by an angle of 45 to one another.

[0035] FIG. 3 shows a representation in perspective of a dual-polarised waveguide 1 with a polarisation-preserving filter according to a second configuration variant. In this configuration variant, the nubs are formed spherically and are grouped in several rings (here: 9) as in the preceding practical example. As is evident from the partially transparent lateral view of the figure, the spherical nubs protrude roughly halfway from the cylindrical inner wall of the basic body 2. As in the preceding practical example, each ring has an identical number of nubs, wherein these are distributed equidistantly over the respective ring, as the front view of FIG. 5 shows. The arrangement of the nubs 3 on the respective rings 4 is such in this case that the adjacent nubs 3 of the rings 4 are arranged on one axis, which runs parallel to the direction of the axial extension (i.e. parallel to the longitudinal axis) of the basic body 2.

[0036] FIGS. 6 to 9 show other practical examples of a dual-polarised waveguide with a circular or cylindrical basic body 2 and different configuration variants of the polarisation-preserving filter realised in this, each in a front view.

[0037] According to the configuration according to FIG. 6, the polarisation-preserving filter has longitudinally elliptical nubs. this practical example, four nubs 3 are arranged on each ring and distributed equidistantly over the circumference of the ring. This means that the nubs 3 are spaced at an angle of 90 from one another and that two nubs come to lie opposite one another respectively. This also applies to the other practical examples in FIGS. 7 to 9. In the practical example according to FIG. 7, the nubs are formed in a cone shape. The practical example according to FIG. 8 shows tetrahedron-shaped nubs. The practical example according to FIG. 9 shows prism-shaped nubs.

[0038] Apart from the configuration variants shown here, other combinations are also conceivable. A polarisation-preserving filter can thus be provided, for example, in which nubs with different structural forms are combined with one another. The combination can take place here in any manner. For example, nubs of one structural form may be provided on one or more rings, while nubs of one or more other structural forms are arranged on one or more other rings.

[0039] In the practical examples shown in FIGS. 1 to 9, the number of nubs 3 chosen per ring is identical. This is not obligatory. In principle, the number of nubs 3 chosen per ring 4 can be different. Thus one ring 4 can comprise four nubs, for example, an adjacent ring 4 five nubs, and so on. Any combinations are conceivable, in which manner the rings 4 can be realised with different numbers of nubs 3.

[0040] In the execution variants shown figuratively here, the dimensions of the nubs 3 are also chosen to be identical in respect of their height and/or their lateral extension (i.e. in an axial direction or transverse to the axial direction). In another configuration, the dimensions of the nubs 3 of one ring or also of adjacent rings may be chosen to be different in respect of their height and/or their lateral extension.

[0041] Furthermore, it is not obligatory, as was shown in the figures, that the nubs 3 are distributed evenly over the circumference of a ring 4. On the contrary, the nubs 3 may be distributed differently, e.g. irregularly, over the circumference of a ring 4, so that the spacings and circumferential angles between two nubs 3 of a ring 4 have different values. It is likewise possible that the nubs 3 are distributed evenly on one ring 4, while the nubs 3 on one or more other rings 4 are distributed unevenly.

[0042] As is clear in particular from the representation in FIG. 4, the spacings of the rings 4 in an axial direction of the circular or cylindrical basic body 2 are chosen to be identical. In a modification of this, the spacings of the rings 4 may also be chosen to be different in an axial direction of the basic body 2. Here combinations may also occur in which some of the rings 4 have an identical spacing from one another in an axial direction and other rings 4 have another spacing from one another.

[0043] A polarisation-preserving filter can be provided hereby with which a first, predetermined frequency band can be transmitted unobstructed and the transmission of a second, predetermined frequency can be blocked. Which frequencies can be transmitted by the polarisation-preserving filter unobstructed and which can be blocked results from the configuration and arrangement of the nubs of the polarisation-preserving filter.

[0044] The suitable choice of the number, the dimensioning of the nubs, the number of rings, the spacings of the rings and the even or uneven distribution of the rings can be discovered by simulation or experiments. In particular, which upper and lower frequency the first and second frequency band assumes can be determined by variation of one of said parameters.

[0045] While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the embodiment in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the embodiment as set forth in the appended claims and their legal equivalents.