EP0293386B1 - Microwave switch with at least two switching positions - Google Patents

Abstract

A microwave switch used to connect selectively at least one coaxial input lead with at least two output leads of which at least one is a coaxial lead, comprises at least one rectangular wave guide passage (8, 9) in the switch rotor (2). In the housing (1) of the switch are mounted wave guide parts (5) of equal sizes and interconnectable through the wave guide passage (8, 9) and connected via adaptor (3) with the input or output coaxial leads.

Description

The invention relates to a microwave switch according to the preamble of the main claim. This is used to switch RF signals.

From DE-OS 31 22 780 a coax T switch is known which has three transmission positions between pairs of four plugs, the switching elements being provided in the form of flat line segments which either lie against the wall of cavities or in the middle of Cavities are arranged. If a line segment lies against the wall of a cavity, it is short-circuited to the cavity and separated from the inner conductors of the coaxial connector. If the line segment is in the middle of the cavity, the ends of the line segment are also in contact with the inner conductors of the coaxial connector, since the inner conductors of the coaxial connector are arranged next to the ends of the line segment.

A cavity is arranged in a certain plane and is in the form of a plurality of cavity parts. The cavity has in particular an outer peripheral part which is divided into three outer cavity parts is. Three radial cavity parts start from a central location in the peripheral part and intersect the ends of the three outer cavity parts. A first coaxial connector is located at the middle point, while three additional coaxial connectors are located at the intersections between the radial cavity parts and the outer cavity parts. A single line segment is arranged in each cavity part, which is movable between a position on the wall of the cavity and from the inner conductors and a middle position in the cavity part in contact with the inner conductor. The total of six line segments correspond in number and shape to the cavity parts, so that three line segments run radially outward from a central location, while three line segments are arranged around the three radial line segments so that they form a circumferential segment.

The various line segments can be operated individually so that signals can be transmitted between pairs of coaxial connectors.

It has been shown that the known coaxial switches have lower reliability and relatively poor high-frequency properties due to the existing mechanical contact. In addition, deteriorate when cascading several such switches, for. B. when used in redundant amplifier circuits, such as those used in space travel, the transmission properties of the signal paths carried over several such switches strong.

The invention is therefore based on the object of designing a microwave switch, of the type mentioned in the preamble of claim 1, in such a way that good transmission properties are achieved in a relatively large transmission bandwidth and this despite a small weight and small dimensions of the microwave switch; this also enables a series connection of several microwave switches with sufficient transmission properties.

This object is achieved by the features mentioned in claim 1. With this solution, the internal transmission within the microwave switch takes place by means of a waveguide. Because of the waveguide passages of the microwave switch, a relatively large transmission bandwidth with good transmission properties is achieved.

Waveguide switches are known per se, for example from DE-OS 29 24 969. Adapters for coupling coaxial lines to waveguides and vice versa also belong to the prior art (DE-AS 23 36 166). Since the standard dimensions of the waveguides for the frequencies to be transmitted would lead to very large and heavy waveguide switches, the person skilled in the art will not consider any waveguide switches to solve the problem. It is only through the further teaching according to the invention of at least reducing the smaller cross-sectional dimension that a viable way using a waveguide switch is found.

An additional weight and volume reduction with a simultaneous increase in the switching options allows a further configuration of the internal waveguide switch. With this internal waveguide switch, the four waveguides are arranged in three planes within the rotor and with their small dimensions parallel to the rotor axis.

A special arrangement of the adapter-coaxial input plugs inserted parallel to the switch axis from one side and coaxial output plugs parallel to the switch axis from the other side - enables straight cable routing without many bends, so that the overall cabling is short and light.

Another advantage of the further configuration of the microwave switch results from the possibility of connecting either waveguide connections of the internal waveguide switch directly or via special waveguides with corresponding cross-sectional dimensions, in order to achieve improved transmission properties in the event of redundancy for the overall circuit and a weight saving in the overall circuit.

Further advantages of the invention result from the description and from the subclaims.

• Fig. 1 den schematischen Aufbau eines erfindungsgemäßen Mikrowellenschalters in einer Schnittdarstellung senkrecht zur Drehachse
• Fig. 2 den schematischen Aufbau eines Rotors des internen Hohlleiterschalters in einer vertikalen Schnittdarstellung, gemäß einer weiteren Ausgestaltung,
• Fig. 3 den schematischen Aufbau des Mikrowellenschalters in einer vertikalen Schnittdarstellung stehend angeordnet mit einem Rotor entsprechend Fig. 2,
• Fig. 4 den schematischen Aufbau entsprechend Fig. 3 eines Mikrowellenschalters in einer horizontalen Schnittdarstellung,
• Fig. 5 eine Redundanzschaltung mit erfindungsgemäß ausgebildeten Mikrowellen-Zweiwegschaltern,
• Fig. 6 eine Redundanzschaltung mit erfindungsgemäß ausgebildeten Mikrowellen-Vierwegschaltern.

The invention is described below with reference to the embodiments shown in the drawings.
Show it:

• Fig. 1 shows the schematic structure of a microwave switch according to the invention in a sectional view perpendicular to the axis of rotation
• 2 shows the schematic structure of a rotor of the internal waveguide switch in a vertical sectional view, according to a further embodiment,
• 3 shows the schematic structure of the microwave switch in a vertical sectional view arranged upright with a rotor corresponding to FIG. 2,
• 4 shows the schematic structure corresponding to FIG. 3 of a microwave switch in a horizontal sectional view,
• 5 shows a redundancy circuit with microwave two-way switches designed according to the invention,
• 6 shows a redundancy circuit with microwave four-way switches designed according to the invention.

1 contains a rotatably mounted rotor 2 in a housing 1. There is a small air gap between the housing and the rotor.

Two adapters 3 are integrated into the housing 1, a third is attached, for example screwed on. The coupling of the RF signals into the waveguide connections is generally known and will not be described in more detail here. To adjust the transmission properties, so-called tuning screws 6, 7 are arranged on the adapters 3. The coaxial connections run at right angles to the waveguides. This arrangement makes sense to save space. A waveguide opening 11 of the housing 1 is provided with a connector 12. This connector 12 performs two functions. To measure the transmission properties of the microwave switch and to adapt the coaxial conductor to the waveguide passages 8, 9 of the internal waveguide switch, a measuring device or a measuring device can be connected here; can also at this connection piece, when using the microwave switch in a redundancy system, another waveguide with a likewise reduced cross-sectional dimension can be coupled, which leads to the next waveguide switch. This has the advantage that there is no need for adapters and that the transmission properties of the overall circuit are improved by eliminating the adapters.

In the case of the waveguide pieces 9, the walls of the small cross-sectional dimensions can be formed from several surface pieces.

2 shows the structure of a rotor 2 according to a further embodiment of an internal waveguide switch in a vertical sectional illustration parallel to the rotor axis. Due to the small dimensions 13 of the waveguide passages arranged parallel to the rotor axis, waveguide passages 8, 9 result in a very flat rotor 2, which is rotatably supported around the rotor axis through 360 °. The rotor 2 contains four waveguide passages 8, 9 for connecting different waveguide pieces (corresponding to 5 in FIG. 1) of the waveguide switch in different switching positions. Two of these internal waveguide passages 8 have the task of connecting opposing waveguide pieces to one another. The two other waveguide passages 9 connect adjacent waveguide pieces to one another. The opposing waveguide pieces 5 interconnecting high-conductor passages 8 are bent near the rotor edge, avoiding sharp kinks, and are guided past the 90 ° waveguide arc passages 9 in a different plane. The chokes 14 serve to reduce crosstalk.

FIG. 3 shows a microwave switch according to the further embodiment of FIG. 2 in a vertical sectional view parallel to the rotor axis with a drive element 20. The drive element 20, for example a stepper motor, is mounted on the housing cover 19 of the microwave switch. Above and below there is an adapter integrated into the housing 1 with the coaxial connectors 16, 17 and the coaxial inner conductors 18 will. The rotor 2 with its bearing (not shown) and the waveguide passages 8, 9 is located in the housing 1 of the microwave switch.

4 shows a microwave switch of the further embodiment in a horizontal sectional view perpendicular to the rotor axis. Direct connections from the internal waveguide switch to the internal waveguide switch can be established via the two flanges 10 via special waveguides of reduced cross-sectional dimensions, or waveguide switches of the further configuration can be coupled directly to one another. In the event of redundancy, frequent transitions between the coaxial line / waveguide or waveguide / coaxial line of the redundancy path are thus eliminated and the transmission properties of the redundancy path are not significantly impaired. In the case of the waveguide bend pieces 9, the walls of the small cross-sectional dimensions are also formed from several surface pieces.

5 shows the use of two-way microwave switches 21-24 according to the invention in a redundancy system, the signals arriving on four coaxial lines AD and outgoing on four of five coaxial lines FI having four two-way switches 21-24 (S switches) designed internally as waveguide switches. , each with four connections I-IV, can be switched. Connections 25-27 from microwave switch to microwave switch 21-24 are either made with special waveguides or the microwave switches are directly connected to one another at the flanges 10. The multiple coaxial conductor / coaxial conductor transitions present in the case of redundancy in the case of coaxial switching and thus the strong attenuation of the signal carried over the redundancy path are thus eliminated. The two-way switches 21-24 are provided at their connections I and II, the microwave switch 21 also at IV with adapters 3 for connecting coaxial lines. The connections III and IV are provided with flanges 10 for the connection of special waveguides. The microwave switch 24 is terminated at connection III.

The signals are fed to the switches via the coaxial lines AD to their coaxial connections I. In the normal case, ie all channels are functional, the switches 21-24 are positioned so that the RF signals are routed to the following amplifiers via the coaxial connections II and the coaxial lines FI. The amplifier connected to the coaxial line E at the terminal IV of the switch 21 is normally not in operation. In the event that, for example, that on the coaxial line H at connection II of the Switch 23 connected amplifier fails, the switch 23 is switched so that the signal on the coaxial line C at the input I of the switch 23 via the flange 10 at the connection IV, the special waveguide 26, the flanges 10 at the connections III and IV of the switch 22 the special waveguide 25, the flange 10 at connection III of the switch 21, the adapter 3 at connection IV of the switch 21 is connected to the functional amplifier connected to the coaxial line E. The signal arriving on the coaxial line C also has only one coax / waveguide and only one waveguide / Roa transition in the redundancy case. In the case of a pure coax switch, the signal would be strongly damped by six coax / coax transitions.

6 shows the use of a four-way micro-switch 28-31 designed according to the invention in a redundancy system, the signals arriving on four coaxial lines AD and outgoing on four non-six coaxial lines with four four-way switches 28-31 (T switches) designed internally as waveguide switches, which each have four connections, can be switched. Here too, the connections from switch to switch are either made with special waveguides or the switches are connected directly to one another at the flanges 10. The four-way switches 28-31 are provided at their connections I and III, the switches 28 and 31 also at IV and II, with adapters 3 for connecting coaxial lines. The connections II of the switches 28-30 and the connections IV of the switches 29-31 are provided with flanges 10 for connecting special waveguides or for directly connecting the internal waveguide switches to one another. Here, too, the signals are fed to the switches 28-31 via the coaxial lines A-D to their coaxial connections I.

In the normal case, ie all channels are functional, the switches 28-31 are positioned so that the RF signals are routed via the coaxial connections III and the coaxial lines FI to the amplifiers connected to the lines FI. The amplifiers connected to the coaxial lines E and K of the switches 28 and 31 are normally not in operation. In the case, that, for example, the two amplifiers connected to the coaxial lines f and G fail, the two switches 28 and 29 are switched so that the signal on the coaxial line A at the input I of the switch 28, via the adapter 3 at the terminal IV and the coaxial line E following amplifier is supplied. The signal on the coaxial line B at the connection I of the switch 29 is via the flange 10 at connection II the special waveguide 33, the flange 10 at connection IV of the switch 30, the flange 10 at connection II, the special waveguide 39, the flange 10 at the terminal IV of the switch 31, the adapter at the terminal II and the coaxial cable K the following amplifier. Here, too, the signals on lines A and B have only one coax / waveguide or waveguide / coaxial transition in the case of redundancy and are therefore not damped as much as with pure coaxial switches.

The special design of the waveguide passages in the switches and the special waveguide between the switches means that their dimensions are chosen to be smaller than the standard dimensions of the waveguides which are usual for the frequencies to be transmitted. The small dimensions are preferably made much smaller. For example at 10 - 15 GHz instead of dimensions of 9.5 mm in height and 19 mm in width, waveguides with dimensions of 4.75 mm in height and 19 mm in width are used.

Reference symbol list

• 1 housing
• 2 rotor
• 3 adapters
• 4 coaxial connectors
• 5 waveguide piece
• 6 tuning screw
• 7 tuning screw
• 8 opposite waveguide sections connecting waveguide passage
• 9 90 ° - waveguide arc piece (adjacent waveguide pieces connecting waveguide passage)
• 10 flange for direct coupling to a waveguide
• 11 waveguide opening
• 12 removable waveguide piece
• 13 small dimensions of the waveguide passage
• 14 choke
• 15 center line parallel to the rotor axis
• 16 coax output connectors
• 17 coax input connector
• 18 coax inner conductor
• 19 housing cover
• 20 drive element
• 21-24 Two-way microwave switch (S switch)
• 25-27 special waveguide pieces or switches flanged directly to each other
• 28-31 four-way microwave switch (T switch)
• 32-34 special waveguide pieces or switches flanged directly to each other
• I-IV switch connections
• A-K coaxial cables

Claims (10)

1. A microwave switch adapted to be set in any one of at least two different switch positions, for optional connection of at least one coaxial input conductor with at least one of two output conductors of which at least one is a coaxial conductor, characterised in that the microwave switch used is an internal waveguide switch with at least one rectangular waveguide passage (8, 9) in the rotor (2) of the switch, and in the casing (1) of the switch waveguide sections (5) are provided which have the same dimensions as one another and can be connected to one another by the waveguide passage (8 or 9) or the waveguide passages (8, 9) and that these sections are connected to the coaxial input and output conductors by way of adapters known per se, and that at least the smaller cross-sectional dimension (13) of the waveguide is made less than the standard dimensions.

2. A microwave switch according to claim 1, characterised in that on the stator side four waveguide sections (5) are arranged in one plane at right angles to one another and have the same dimensions as one another, that the rotor (2) of the internal waveguide switch has at least one waveguide throughput (8) connecting at least one pair of opposite waveguide sections (5) with one another, and two further waveguide throughputs (9) interconnecting two waveguide sections (5) formed as 90° waveguide arc sections.

3. A microwave switch according to claim 2, characterised in that at least two waveguide sections (5) located opposite one another are provided with adapters (3).

4. A microwave switch according to claim 3, characterised in that at least one of the waveguide sections (5) is adapted to be directly coupled to a waveguide having the same dimensions.

5. A microwave switch according to claim 4, characterised in that the waveguide to be coupled is the waveguide section (5), on the stator side, of a further internal hollow switch.

6. A microwave switch according to any one of claims 1 to 5, characterised in that the waveguide sections (5) and the waveguide passages (8,9) are arranged with their small cross-sectional dimensions (13) in the direction of the axis of the switch.

7. A microwave switch according to any one of claims 2 to 5 and 6, characterised in that the waveguide arc sections (9) are arranged in one plane and that when only one waveguide passage (8) interconnecting opposite waveguide sections (5) is used, this passage is curved away in the vicinity of the rotor edge and extends in another plane past the waveguide arc sections (9).

8. A microwave switch according to any one of claims 2 to 5 and 6, characterised in that the waveguide arc sections (9) are arranged in one plane and that when two waveguide passages (8) interconnecting opposite waveguide sections (5) are used these passages are curved away in the vicinity of the rotor edge and extend in different planes past the waveguide arc sections (9).

9. A microwave switch according to any one of claims 1 to 8, characterised in that the coaxial input conductor is connected to the microwave switch parallel to the switch axis from one side, and the coaxial output conductor is connected to the microwave switch parallel to the switch axis from the other side (fig. 3).

10. A microwave switch according to any one of claims 1 to 9, characterised by its use for optionally connecting n coaxial input conductors (A to D) to n out of (n + a) (a = 1 or 2) coaxial outgoing conductors (E to K) in such a manner that n microwave switches are used with at least two waveguide passages (8,9), of which the 2nd. to (n - 1)th microwave switch each has a coaxial input and a coaxial output and two waveguide outputs, whereas the first and/or nth microwave switch each has a coaxial input and two coaxial outputs and a waveguide output, that the coaxial outputs are each coupled to a respective coaxial outgoing conductor and that each waveguide connection of a microwave switch is connected to a respective waveguide connection of an adjacent microwave switch, and when at least one switch is changed over this results in connection of the n input conductors to the required n output conductors.

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