DE3244746A1 - Dielectric flexible waveguide - Google Patents

Abstract

A dielectric flexible waveguide, especially for millimetre waves. Its external profile has recesses (2) to increase the flexibility and is coated with an electrically conductive metallic coating (3). (FIG.). <IMAGE>

Description

Dielectric flexible waveguide

The invention relates to a dielectric flexible waveguide, especially for millimeter waves.

Known dielectric waveguides are unshielded conductors that Have radiation losses and therefore only as short transition pieces or as an antenna are usable. Metallic flexible waveguides are known, however.

require high manufacturing costs, especially for high frequencies, and are therefore expensive. It is also known to have a rigid metallic waveguide Line dielectric.

The object of the invention is to provide a waveguide of the type mentioned at the beginning Specify type that is particularly flexible, mechanically stable and inexpensive to manufacture and has no radiation lice and can therefore be used in any length is.

The invention is characterized in claim 1. The others Claims contain advantageous developments and embodiments of the invention.

The invention is illustrated below with reference to the figure, which is a preferred one Embodiment shows, explained in more detail.

The waveguide 1 is made of a dielectric with a low dielectric constant and low loss factor, preferably made of Teflon. The dielectric is flexible and insensitive to environmental influences. To increase flexibility of the waveguide has its outer profile parallel recesses, but preferably Recesses 2 with a thread-like shape.

Such thread-like grooves can be made with a round full conductor very easy to produce in continuous passage with a cutting nozzle.

The outer profile of the waveguide is electrically conductive metallic coating 3 coated. This consists of one or more metal layers, the number and nature of which are adapted to the mechanical requirements. the Coating 3 must be sufficiently flexible and is therefore relatively thin; the layer thickness but must be greater than the penetration depth of the waves to be guided in waveguide 1, to eliminate radiation losses.

Step when the waveguide 1 bends or when the temperature changes high tensile stresses on the coating 3. With the waveguide according to the invention however, these are reduced to a permissible one by the shape of the grooves 2 Bending stress on the flanks of the profile.

Likewise, the thermal stresses of the greatly different expansion coefficients reduced by dielectric and metal.

In a further development of the invention, the waveguide 1 protrudes at its ends with a conical transition 4 into a rigid, air-filled metallic waveguide 5 in.

The transition 4 can be an inner cone or an outer cone. The inner cone has the advantage that it is still produced after the dielectric has been introduced or can be edited afterwards. Both cone shapes need to go to the beginning of the cylindrical part of the dielectric conductor free of a metallic coating be. This is achieved by means of suitable, subsequently removable covers, which are applied before the metallization process, or by machining Machining the dielectric after metallization. The flexible conductor t can by soldering or a conductive adhesive connection 8 to the coating 3 be fixed on the rigid waveguide 5. The waveguide ends with a standard flange 6th

Since with the same cut-off frequency the inside diameter of the dielectric filled waveguide is less than that of the air-filled waveguide 5, has this has a tapered cross-sectional constriction 7 in the region of the transition 4.

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Claims (7)

Claims.) Dielectric more flexible. Waveguides, in particular for millimeter shafts, characterized in that its outer profile has recesses (2) to increase flexibility and with an electrically conductive metallic Coating (3) is coated. 2. Waveguide according to claim 1, characterized in that the Recesses - (2) have a thread-like shape. 3. Waveguide according to claim 1, characterized in that it is is a round full conductor (1). 4. Waveguide according to claim 1, characterized in that the metallic coating (3) consists of several metal layers. 5. Waveguide according to one of the preceding claims, characterized in that that it has a conical transition (4) at its ends into a rigid air-filled one metallic waveguide (5) protrudes, which is terminated with a standard flange (6) is, and that in the area of the conical transition (4) the metallic coating away. 6. Waveguide according to claim 5, characterized in that the transition (4) is designed at its ends as an outer or an inner cone. 7. Waveguide according to claim 5, characterized in that the metallic Waveguide (5) has a tapered cross-sectional constriction in the area of the conical transition (4) (7).