DE1048970B - Waveguide for the transmission of electromagnetic tube waves from the H01 mode - Google Patents

Description

GERMAN

The invention relates to a waveguide for the transmission of electromagnetic tubular waves from the H ₀₁ mode

As is known, the H ₀₁ pipe waves are characterized in that their electric field is transverse to the direction of propagation of the waves and is essentially circular in the cross-sectional planes of the pipe. As a result of this special field structure, the H ₀₁ tubular shafts have the advantageous property that their damping decreases with increasing frequency. Due to this property, the H ₀₁ tubular shafts are becoming more and more important at the frequencies already in use today in the order of GHz, where it is a matter of transmitting high-frequency signals over long distances with little attenuation.

In addition to this favorable behavior, however, the H ₀₁ tubular shafts also show properties that prevent interference-free transmission. One of these is primarily the instability, which manifests itself in the fact that even slight irregularities in the structure of a smooth, homogeneous pipe with a circular cross-section can cause the H ₀₁ pipe waves to split into other wave modes, especially an E ₁₁ wave . This is related to the fact that in smooth, homogeneous tubes with a circular cross-section, the transmission _{factor or the phase dimension or - formulated mathematically - the eigenvalue of the H 01} tubular shaft coincides with the corresponding sizes of an E ₁₁ shaft. This correspondence in the transmission measures also means that the

build. It has also been proposed to wind one or more metal strips upright to form a tube. This inhomogeneous design of a H _ni waveguide reduces the instability of the H,

01

Tubular corrugation largely abolished, namely in that the H ₀₁ tubular corrugation has a different propagation dimension than the E ₁₁ corrugation in such inhomogeneous tubes. The same effect can also be achieved by deforming a circular smooth tube into an elliptical tube.

In contrast to the known solutions, the new waveguide is characterized in that, according to the invention, it consists of an elliptical tube twisted around the longitudinal axis of the waveguide. Through the gate waveguide for transmission
of electromagnetic tube waves
from H ₀₁ mode

Applicant:
Siemens & Halske Aktiengesellschaft,
Berlin and Munich,
Munich 2, Wittelsbacherplatz 2

Ernst Fischer, Berlin-Lichterfelde, has been named as the inventor

By using an elliptical tube, the advantage is achieved from the outset that the H ₀₁ waveguide can be bent more easily and thus it is possible to wind it on large-diameter drums. In addition to this purely mechanical advantage, the twisting also provides a favorable one

H ₀₁ tubular shaft is _{strongly coupled to the E 11} shaft, so that energy is withdrawn from _{the H 01} tubular shaft by the E ₁₁ shaft and the transmission energy oscillates back and forth _{between the H 01} tubular shaft and the E _{11 shaft.}

To this effect to prevent or at least reduce, it is known, the H-aufzu effect -Hohlleiter ₀₁ of individual insulated from each other rings, or from a molded into a helix round wire to the physical propagation process of an H ₀₁ -Rohrwelle exerted. To understand this effect, reference should be made briefly to the physical processes in the curvatures of an elliptical H ₀₁ waveguide, FIGS. 1 and 2 serving as an example.

In the curvatures of H ₀₁ waveguides, two modes of an E ₁₁ wave can develop, which are to be referred to for short as even mode E ₁₁ 'and odd mode E ₁₁ ". In FIGS. 1 and 2, these two modes are schematic 1 shows the even mode E ₁₁ 'and FIG. 2 shows the odd mode E ₁₁ "in an elliptical tube with the major semiaxes a and the minor semiaxes b . These two modes have mutually different propagation measures or phase measures, of which the phase measure of the odd mode E ₁₁ "has the greatest deviation from the phase _{measure of the H 01} tubular wave. What is remarkable is the phenomenon that the H ₀₁ tubular wave is coupled with that mode is, in which the connecting line between the two marked points A and B of the field line image thus perpendicular to the plane of curvature of the pipe. standing the large Halbachsena of the elliptical tube perpendicular to the plane of curvature, the H is ₀₁ -Rohrwelle with

809 730/310

Claims (5)

coupled to the even mode Eil 'according to FIG. If, on the other hand, the two small semi-axes b are aligned perpendicular to the plane of curvature, there is a coupling between the H01 tubular shaft and the odd mode E11 "according to FIG It is therefore desirable to bend the elliptical tube in the curvatures of the transmission path so that the small semiaxes b are perpendicular to the plane of curvature. This means that the favorable effect with regard to the transfer process is achieved when the elliptical tube is curved in that lateral direction according to which it has the greatest mechanical stability against bending deformations by its nature. Apart from the fact that such bending deformations can only be carried out with the required accuracy in an elliptical tube with difficulty, there is also the disadvantage that when designing elliptical H01 waveguides it can happen that the major semi-axes of the elliptical tube protrude from the Turn out the plane of curvature or that the surface of curvature itself is not flat, so that an unambiguous assignment of the semiaxes of the elliptical tube to the surface of curvature is not possible at all or only with great difficulty. This creates the risk that the H01 tubular waves are coupled over a longer distance with the unfavorable straight mode E11 'of the E11 wave. The twisting according to the invention of an H01 waveguide in the form of an elliptical tube creates a kind of statistical compensation which prevents coupling of the H01 tubular shaft with the straight mode E11 'over longer distances. 3 to 7 show embodiments of a waveguide according to the invention and a device for its production. According to FIG. 3, the H01 waveguide consists of an elliptical tube 1 which is twisted. The tube is preferably made of aluminum and has a mirror finish as possible on its inner surface. The mirror-like finish of the inner surface of the pipe can be achieved, for example, with a suitable pull nipple. 4 shows a twisted elliptical pipe section 2 of an H01 waveguide, which is provided with a flange 3 at each of its ends. In this case, the H01 waveguide is composed of several such pipe sections 2, which are connected to one another at their flanges. In FIG. 5, a rotated elliptical tube 4 is again shown. In the grooves of this twisted pipe, lines 5, for. B. signal or supply lines housed. By accommodating additional lines, in addition to the good use of space, the advantage is achieved that the cable in its final form with the usual protective armoring, which is shown schematically in the figure and denoted by 6, has a circular cylindrical shape. 6 shows a further example of an H01 waveguide in which the helical grooves in the twisted elliptical tube are filled with additional lines. The twisted elliptical tube is denoted by 7. In this exemplary embodiment, the additional lines 8 are embedded in insert strips 9 made of insulating material, which fill the grooves of the twisted elliptical tube 7. A manufacturing method for an H01 waveguide according to the invention and a device suitable for carrying out this method are described below with reference to FIG. 7. In the figure, 10 schematically represents a pipe press. The pressed, preferably made of aluminum, pipe 11 with a circular cross-section leaves the pipe press in the direction of the arrow and enters a drawing die 12 with an elliptical bore. In the interior of the tube, at the location of the drawing tool 12, a drawing nipple, not shown in detail, is arranged in the form of an ellipsoid. The pull nipple is attached to a pull rod 13, which protrudes with its free end from the free side of the pipe press. The circular tube 11 is brought into the desired elliptical shape both by the drawing die 12 and by the drawing nipple. The twisting is carried out at the same time as the elliptical deformation. This is done in that the drawing iron 12 via a ring gear 14 and the drawing nipple via a gear 15 attached to the free end of the pulling rod 13 and both together via a corresponding drive device from a common drive motor 16 are set in synchronous rotation. This process is expediently carried out using lubricants. The removal of the lubricant can be done, for example, in the case of a pipe located on a drum, in such a way that the solvent is introduced into the finished pipe from the end. The drum is then set in rotation so that the solvents slowly migrate through the entire pipe. Instead of a solvent, washing and rinsing agents can also be used alternately, which flow through the pipe in sections one after the other when the drum is rotated. The invention is not restricted to the exemplary embodiments shown; these can be modified in many ways within the scope of the invention. Claims. 1. Waveguide for the transmission of electromagnetic tubular waves from the H ₀₁ mode, characterized in that it consists of an elliptical tube twisted around the waveguide longitudinal tube. 2. Waveguide according to claim 1, characterized in that the helically extending Grooves of the twisted pipe with additional lines, for example with signal and supply lines, are filled in ". 3. Waveguide according to claim 2, characterized in that the additional lines in insert strips made of insulating material are embedded. 4. Waveguide according to claim 1, characterized in that the tube is made of aluminum. 5. A method for producing a waveguide according to claim 1, characterized in that the preferably aluminum pressed pipe after leaving a pipe press through a drawing iron or a rolling device and one inside the pipe at the location of the drawing iron Body located in the rolling device (drawing nipple) is deformed elliptically in the form of an ellipsoid, whereby at the same time the drawing iron or the rolling device and the drawing nipple rotate in the same direction rotate their axes lying in the pipe axis.